System and method for ion implantation

Abstract

An ion implantation system and method implants a modified energy ion beam across one workpiece in a series of single-workpiece terminal stations, wherein electrodes, bending electrodes, and / or energy filters of an acceleration / deceleration stage control the ion beam to a final energy or path on the workpiece. The bending electrode or energy filter may form part of the acceleration / deceleration stage or may be located downstream. A scanning device scans the ion beam and / or the workpiece, and a power supply provides a modified electrical bias signal to the electrodes. A controller selectively modulates the electrical bias signal during the scanning of the ion beam and / or via the ion beam on the workpiece, based on a desired ion beam energy at the workpiece. A waveform generator provides the modification and synchronizes the electrical bias signals supplied to the acceleration / deceleration stage, bending electrodes, and / or energy filters.

Description

[Technical Field]

[0001] This invention generally relates to ion implantation systems, and more particularly, to a system and method for providing continuously controlled variable energy to an ion beam delivered to a workpiece during ion implantation. Cross-Reference to Related Applications

[0002] This application claims the benefits of U.S. Provisional Application No. 63 / 229,751, filed August 5, 2021, entitled “BLENDED ENERGY ION IMPLANTATION” and U.S. Provisional Application No. 63 / 229,663, filed August 5, 2021, entitled “CHAINED MULTIPLE ENERGY IMPLANT PROCESS STEPS”, the contents of which are incorporated herein by reference in their entirety. [Previous Technology]

[0003] In the manufacture of semiconductor devices, ion implantation is used to dope semiconductors with impurities. Ion implantation systems are often used to dope workpieces (such as semiconductor wafers) with ions from an ion beam to produce n-type or p-type material doping, or to form a passivation layer during the manufacture of integrated circuits. This beam processing is often used to selectively implant wafers with impurities of a specified dopant material at a predetermined energy level and with a controlled concentration to produce semiconductor material during the manufacture of integrated circuits. When used to dope semiconductor wafers, the ion implantation system implants selected ionic material into the workpiece to produce the desired intrinsic material. For example, implantation with ions generated from a source material (such as antimony, arsenic, or phosphorus) produces an "n-type" intrinsic material wafer, while a "p-type" intrinsic material wafer is often produced by ions generated using a source material (such as boron, gallium, or indium).

[0004] A typical ion implanter includes an ion source, an ion extraction device, a mass analysis device, a beam delivery device, and a wafer processing device. The ion source generates ions of the desired atomic or molecular dopant species. These ions are extracted from the source by an extraction system (typically a set of electrodes) to form an ion beam, which powers and guides the ion stream from the source. The desired ions are separated from the ion beam in a mass analysis device, typically a magnetic dipole that performs mass dispersion or separation of the extracted ion beam. The beam delivery device (typically a vacuum system containing a series of focusing devices) delivers the ion beam to the wafer processing device while maintaining or modifying the desired properties of the ion beam. Finally, the semiconductor wafer is transferred into or out of the wafer processing device via a wafer handling system, which may include one or more robotic arms for placing the wafer to be processed in front of the ion beam and removing the processed wafer from the ion implanter.

[0005] Current ion implantation technology is based on a recipe for implanting ions into a workpiece (also known as a substrate or wafer) under specific conditions. This recipe results in a given concentration and depth profile of ions implanted within the substrate, typically determined by the type or desired species of dopant, the density and composition of the workpiece, and implantation conditions (such as the energy of the implanted species (which determines the depth of ion implantation)), the implantation angle of the workpiece surface relative to the ion beam (e.g., tilt or twist), and the total implantation dose. Additionally, variables such as the workpiece temperature and / or the charge state of the implanted ions can be controlled in the implantation recipe to provide the desired implantation result.

[0006] To establish the desired dopant profile, multiple implantations of the same species are typically performed on the same substrate (usually using different combinations of energy, dose, tilt, or twist). While dose, tilt, and twist can be adjusted within a single implantation by breaking it down into multiple implantation steps, each with different input parameters, changing the implantation energy to alter the implanted ion depth often requires significant adjustments and / or modifications to various settings and / or the electrical bias signals applied to the power supply and / or components of the ion implantation system to maintain the integrity of the desired ion beam characteristics (e.g., beam tuning). Such adjustments and / or modifications typically increase the time required to set up the ion implantation system (so-called tuning time), thus impacting the productivity of the ion implantation system. Furthermore, these beam tuning steps may require the removal and repositioning of workpieces, such as those used to place the wafer in front of the ion beam on workpiece supports or clamps, which can further affect system productivity and yield due to workpiece handling. [Summary of the Invention]

[0007] This invention provides a system and method for delivering a specific distribution of energy (e.g., at equal or varying doses and / or angles) within a single, continuous delivery procedure. Therefore, a simplified overview of the invention is presented below to provide a basic understanding of some aspects of the invention. This overview is not a comprehensive summary of the invention. It is not intended to identify key or essential elements of the invention, nor to describe the scope of the invention. Its purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that follows.

[0008] According to one embodiment of the present invention, an ion implantation system is provided, wherein an ion source is configured to ionize a doped material and generate an ion beam. For example, a beamline assembly is positioned downstream of the ion source and configured to deliver the ion beam toward a workpiece. For example, a scanning device is configured to scan one or more of the ion beam and the workpiece relative to each other along a first scanning axis, and an acceleration / deceleration stage is provided and configured to receive the ion beam during delivery. A terminal station is positioned downstream of the acceleration / deceleration stage, wherein the terminal station includes a workpiece support configured to selectively position the workpiece in one path of the ion beam.

[0009] For example, one or more power sources are operatively coupled to the acceleration / deceleration stage, wherein the one or more power sources are configured to provide one or more electrical bias signals to the acceleration / deceleration stage. For example, the acceleration / deceleration stage is configured to define a plurality of energies of the ion beam based on the one or more electrical bias signals.

[0010] For example, a controller is configured to selectively modulate one or more electrical bias signals provided to the acceleration / deceleration stage while scanning one or more of the ion beam and the workpiece along the first scanning axis. In one instance, the selective change of the one or more electrical bias signals is based at least in part on the position of the ion beam relative to one of the workpieces and across a predetermined embedding profile of one of the workpieces.

[0011] According to another example, a method for ion implantation is provided, wherein an ion beam is directed to a workpiece, and one or more of the ion beam and the workpiece are scanned relative to each other, thereby implanting ions into the workpiece. While scanning the ion beam and one or more of the workpieces, the energy of one of the ion beams is selectively changed, at least in part, based on the position of the ion beam relative to one of the workpieces and across a predetermined implantation profile of one of the workpieces. This changes the implantation depth of ions into one of the workpieces during the scanning.

[0012] According to another embodiment, an ion implantation system is provided, comprising an ion source configured to generate an ion beam and an acceleration / deceleration stage. For example, the acceleration / deceleration stage is configured to receive the ion beam to generate a final ion beam having an associated final energy. For example, a workpiece support is configured to selectively position a workpiece along a path of the final ion beam, and a scanning device is configured to scan one or more of the ion beam and the workpiece support relative to each other along a first scanning axis and a second scanning axis.

[0013] For example, one or more power supplies are operatively coupled to the acceleration / deceleration stage and configured to provide it with one or more electrical bias signals. For example, the one or more electrical bias signals may include one or more of a voltage and a current. For example, a waveform generator is further operatively coupled to one or more of the one or more power supplies, wherein the waveform generator is configured to controllably apply a waveform to the one or more electrical bias signals.

[0014] Additionally, for example, a controller is operatively coupled to the one or more power supplies and the waveform generator, wherein the controller is configured to selectively change the one or more electrical bias signals supplied to the acceleration / deceleration stage while scanning one or more of the ion beam and the workpiece support. Thus, a plurality of energies of the ion beam are implanted into the workpiece in a predetermined manner. For example, the selective change of the one or more electrical bias signals supplied to the acceleration / deceleration stage is at least partially based on the waveform, a position of the ion beam relative to one of the workpieces, and a predetermined energy of the ions implanted into the workpiece.

[0015] According to yet another example, an ion implantation system is provided, comprising an ion source configured to form an ion beam and guide the ion beam to a workpiece. For example, one or more beamline assemblies are configured to deliver the ion beam along a beam path, and a scanner device is configured to selectively and repeatedly scan one or more of the ion beam and the workpiece along a first scanning axis. An acceleration / deceleration stage is located downstream of the scanner device, and a power supply is configured to provide a bias signal to the acceleration / deceleration stage. For example, a controller is configured to change or modulate the bias signal provided from the power supply to the acceleration / deceleration stage as the ion beam and one or more of the workpiece are repeatedly scanned along the first scanning axis, thereby selectively changing the final energy of one of the ions implanted into the workpiece along the first scanning axis.

[0016] In another example, an ion implantation system is provided, comprising a power supply configured to provide an electrical bias signal corresponding to a predetermined waveform. For example, an energy-changing component is configured to receive the electrical bias signal to selectively change an ion beam to a final energy based on the predetermined waveform, wherein the final energy is selectively changeable.

[0017] According to another example, a method is provided for ion implantation of a single workpiece using a single tuned formulation at different predetermined energies through a plurality of sequential implantation steps. The method includes configuring ion implantation parameters to implant an ion beam at a first predetermined energy, and establishing a first minimum ion beam angle associated with the first predetermined energy. Based on the establishment of the first minimum ion beam angle associated with the first predetermined energy, an ion beam orientation angle is defined relative to the single workpiece. For example, the plasma implantation parameters are adjusted to implant an ion beam at a second predetermined energy, and a minimum ion beam angle associated with the second predetermined energy is established. For example, the ion beam orientation angle is further controlled relative to the workpiece based on the establishment of the minimum ion beam angle associated with the second predetermined energy. Additionally, the workpiece is processed to implant ions therein at the first predetermined energy and the second predetermined energy in the sequential implantation steps, while the ion beam orientation is adjusted relative to the workpiece with each sequential implantation step.

[0018] In another example, a method is provided for implanting ions into a single workpiece using a single tuned formulation at different predetermined energies through a plurality of sequential implantation steps, wherein one or more ion implantation parameters are configured to implant an ion beam at a first predetermined energy. The one or more ion implantation parameters are further configured to implant an ion beam at a second predetermined energy, and the ions are sequentially implanted into the workpiece at the first predetermined energy and the second predetermined energy.

[0019] In another example, a method is provided for implanting ions into a single workpiece using a single tuned formulation at different predetermined energies through a plurality of sequential implantation steps. For example, one or more ion implantation parameters are configured to implant an ion beam at a first predetermined energy, and a minimum ion beam angle associated with the first predetermined energy is established. Based on the establishment of the minimum ion beam angle associated with the first predetermined energy, a first ion beam orientation angle is defined relative to the workpiece, and the one or more ion implantation parameters are controlled to implant an ion beam at a second predetermined energy. For example, a minimum ion beam angle associated with the second predetermined energy is further established, and a second ion beam orientation angle is defined relative to the workpiece based on the establishment of the minimum ion beam angle associated with the second predetermined energy. Ions are further sequentially implanted into the workpiece at the first predetermined energy and the second predetermined energy, while controlling the respective first and second ion beam orientations relative to the ion beams.

[0020] To achieve the foregoing and related objectives, the present invention includes the features fully described below and particularly pointed out in the claims. Certain illustrative specific examples of the invention are set forth in detail below with reference to the accompanying drawings. However, these specific examples indicate several of the various methods and approaches employing the principles of the invention. Other objectives, advantages, and novel features of the invention will become apparent from the following detailed description of the invention (when considered in conjunction with the drawings).

Implementation Method

[0028] To achieve the foregoing and related objectives, the present invention includes the features fully described below and particularly pointed out in the claims. Certain illustrative specific examples of the invention are described in detail below and accompanied by the drawings. However, these specific examples only indicate a few of the various ways in which the principles of the invention can be used. Other objectives, advantages, and novel features of the invention will become apparent from the following detailed description of the invention (when considered in conjunction with the drawings).

[0029] Therefore, the present invention will now be described with reference to the accompanying drawings, wherein the same reference numerals throughout may refer to the same elements. It should be understood that such descriptions are illustrative only and should not be interpreted in a limiting sense. In the following description, numerous specific details are set forth for purposes of explanation in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without each of these specific details.

[0030] The present invention provides a system and method for delivering a specific distribution of energy (e.g., with equal or varying doses and / or angles) within a single, continuous delivery sequence without prior noticeable adjustments and / or workpiece handling. For example, the invention provides methods ranging from simple methods for delivering two independent delivery energies in a single delivery to more complex methods having a continuous distribution or energy range within a predetermined range, which has a fixed or controlled dose and / or beam angle gradient across the energy distribution or range. For example, the invention can be utilized when there is a need to generate a so-called box profile of dopant concentration versus depth (which can be advantageous in semiconductor device manufacturing).

[0031] Furthermore, the present invention provides pre-tuning of an ion implantation system for a plurality of formulations prior to implantation. For example, it is advantageous to pre-tune various components of the ion implantation system for all a plurality of formulations for a given workpiece before implantation begins, thereby selectively implementing each of the plurality of formulations for implantation into each workpiece in a single implantation or in a series of implantation steps that can be handled or performed without removing the workpiece from the workpiece support.

[0032] The present invention provides a continuous energy distribution, or so-called "hybrid energy" implantation, thereby dynamically changing and controlling the energy of the ions implanted into the workpiece in each pass of the ion beam across the workpiece surface. This control implements a time-varying bias signal (e.g., voltage and / or current) applied or otherwise provided to one or more power supplies associated with an acceleration / deceleration stage (also referred to as an acceleration / deceleration electrode). Furthermore, the scanner waveform used to scan the ion beam and / or control one or more post-final energy elements may be further based, at least in part, on the time-varying bias signal applied to one or more power supplies associated with the acceleration / deceleration stage, which may include angular energy filters or "AEFs," typically including bending elements, etc.

[0033] For example, a time-varying voltage can be applied to one or more power supplies associated with an acceleration or deceleration stage to provide a continuously controlled variable energy ion beam to the workpiece for its ion implantation. Additionally, one or more beam bending elements configured to bend the ion beam once it reaches its final energy can be "disconnected" from the time-varying voltage applied to one or more power supplies associated with the acceleration / deceleration stage, thereby maintaining a fixed angle or continuously changing the angle at which the variable energy ion beam strikes the workpiece.

[0034] In one example, the time-varying voltage can be achieved by incorporating a waveform generator operatively coupled to one or more power supplies and configured to apply one or more waveforms to them. For example, a controller is configured to change, alter, maintain, or otherwise supply the time-varying voltage to individual acceleration / deceleration stages and / or final energy elements.

[0035] In one example, the present invention provides waveforms, energies, and calibration factors that are rapidly switched based on the workpiece position (e.g., a slow scan or vertical position of the workpiece relative to the ion beam) for various hardware designs. Therefore, the present invention provides a sufficiently fast response time to be compatible with various other dose and energy patterning functions that can be implemented during ion implantation cycles.

[0036] As previously noted, the energy control and adjustment capabilities provided by the present invention advantageously minimize the handling of workpieces being processed. For example, compared to conventional systems where workpieces are transferred multiple times between the load-locking chamber and the processing chamber to achieve multi-energy placement, the present invention can place all the required energy into the workpiece while maintaining the workpiece on the processing chamber and workpiece support without removing it. This results in lower yield losses attributable to handling errors or standby time effects and significantly increases the workpiece throughput in the ion placement process.

[0037] The present invention is ideally suited for beamline installers with downstream acceleration / deceleration capabilities (e.g., hybrid scanning installers with dot beams and single-wafer installers with scan points or strip beams). To maintain energy purity, such installers may also have optional angle energy filters to selectively install the substrate with the beam at a specified desired final energy (e.g., to filter out disabling particles). For example, while the present invention does not exclude and has installers with upstream acceleration components or post-acceleration magnets for beam parallelism, such plasma installers may be limited by the speed of adjustment required in the magnet current (to match the performance of voltage-based post-acceleration, downstream acceleration, and AEF-based tools) due to the influence on downstream components. Therefore, the present invention does not exclude the use of magnetic or electrostatic beamline elements for post-acceleration to achieve capabilities similar to other specific examples listed herein. However, it should be understood that the present invention offers its greatest advantage in systems having downstream acceleration or deceleration components and / or in combination with downstream angular bending components, wherein rapid energy changes can be implemented without altering or modifying the electrical bias of upstream components such as ion sources, extraction electrodes, mass analyzers, scanner correctors or parallelizers and the like.

[0038] It should also be noted that although plasma-wetting ion implantation (PIII) or plasma doping tools can also be used to generate voltage ramps to produce similar doping profiles to those provided by the present invention, the present invention described herein provides a path for dynamically tunable implantation energy for quality-selective species over an energy range that is much wider than that actually possible with plasma doping.

[0039] The present invention can provide a predetermined number of energies (e.g., any large number of energies) to produce a typically mixed box-shaped dopant energy distribution that cannot be achieved with only a few ion implantation passes at different energies. For example, to achieve this, deceleration, acceleration, and any angular deflection are controlled by synchronizing a time-varying voltage or current at a frequency (e.g., an order of magnitude or higher) higher than any fast or slow scan of the workpiece or ion beam.

[0040] For example, the shape of the bias signal or waveform applied to the accelerating / decelerating electrodes can also be used to adjust the dose weighting of the energy distribution tuning for dopant and / or energy profile. Energy can be mixed at frequencies much higher than the horizontal scan of the ion beam, thereby enabling the use of a single horizontal angle tuning, a single uniformity correction waveform, a single vertical angle offset value, and a single dose reference for energy mixing (e.g., each horizontal and vertical beam angle or flux measurement may include the entire energy distribution). Eliminating the need to tune each energy discretely reduces the total setup time for the ion implantation system while producing a unique mixed dopant profile.

[0041] One advantageous aspect of the present invention is that it enables the generation of a dopant distribution profile that is smoother than the profile that can be reasonably generated by a series of discrete ion implantation processes under some energy subsets (e.g., where a "box-shaped" profile is required).

[0042] Therefore, according to the invention, the wave generator is configured to perform high-frequency changes in the voltage bias applied to the acceleration / deceleration column, thereby providing an ion beam with continuously varying energy. The invention can be advantageously implemented using a scanning pencil beam or a so-called scanning dot beam architecture because the energy can be advantageously changed downstream of the scanner via a single component defining the final energy of the ion beam, thus providing numerous advantages regarding tuning and other variability that might be undesirably introduced when using upstream components to change the energy.

[0043] The present invention provides a productivity advantage over conventional systems by eliminating workpiece exchange or switching time and setting time by deploying multiple energies, without having to retun the beam or move the workpiece to and from the workpiece holder and / or terminal station. In a particular specific embodiment, the present invention anticipates providing a high-frequency variable power supply to an acceleration / deceleration voltage and a selectable bending voltage, thereby providing control to synchronize the acceleration / deceleration voltage with the bending voltage to maintain a constant angle of the ion beam at the workpiece. Thus, compared to deploying the workpiece with a first energy at a first dose and / or angle, modifying the system to deploy at a second energy, and then deploying the workpiece with a second energy at a second dose and / or angle, a continuously controlled variable distribution of energy is provided at the workpiece, thus deploying all energy on the workpiece in a single operation.

[0044] The present invention provides a system and method for continuously changing, modulating, oscillating, or switching the energy used for implantation within a predetermined range when scanning one or more of an ion beam and a workpiece. For example, a waveform is applied to generate a predetermined energy profile, thereby defining a custom dopant distribution within the workpiece that would not otherwise be obtainable by conventional ion implantation. In one instance, although a very large number (e.g., hundreds) of ion implantation energies may be required, for productivity reasons, this very large number of energies will be broken down into a smaller number of discrete energies (e.g., 20 to 30 energies) that will attempt to approximate the desired implantation profile within a predetermined energy range.

[0045] However, in conventional beamforming, even when the beamline is adjusted for each of a small number of discrete energies, the typically required setup and retuning (e.g., 20 to 30 times) results in unacceptably significant time for setting up or tuning the multi-energy beamforming. Furthermore, conventionally, during each beam tuning step, it may be necessary to remove the workpiece from its position on the workpiece support (e.g., a pressure plate, chuck, or electrostatic clamp (ESC)) and / or processing chamber, thereby further extending the processing setup time and potentially causing particle contamination and / or workpiece disposal problems.

[0046] In contrast, according to the present invention, only one beamline setting is performed because the energy is continuously converted or dynamically changed. For example, if a planting energy of 5 keV to 25 keV is required, a conventional planting procedure can be divided into nine discrete passes of the workpiece through the ion beam, thereby changing the energy in the discrete steps between each pass (e.g., 5 keV; 7.5 keV; 10 keV; 12.5 keV; 15 keV; 17.5 keV; 20 keV; 22.5 keV; 25 keV). However, more typically, given the significant settling time required between each pass, the desired 5 keV to 25 keV planting may be decomposed into three planting steps, such as 5 keV, 15 keV, and 25 keV, resulting in a relatively non-uniform aggregated dopant profile, which may be unacceptable.

[0047] However, compared to what is conventionally observed by continuously varying the energy of an ion beam during a single pass over a workpiece in a predetermined manner, the present invention provides a significantly more uniform energy profile within a predetermined energy range. It should be noted that the terms "continuously" and "constantly" are intended to imply energy variations or changes along a single pass of the ion beam relative to the workpiece, and may include various continuous and / or gradual waveforms or increments. Thus, the energy changes at a high rate as the ion beam sweeps across the workpiece. For example, this change may be a constant oscillation or a change at a sufficiently high frequency such that all locations on the workpiece are exposed to all varying energies. The resulting aggregate or total energy profile is more uniform or "box-shaped."

[0048] In one example, the beam may move across the workpiece along a first axis in a so-called fast scanning direction (e.g., horizontal direction) (e.g., electrostatic scanning), such as at a horizontal scan rate of approximately 41 Hz. Thus, for example, the horizontal movement of the beam can be quantized as approximately 1000 steps across the workpiece. In a slow scanning direction (e.g., vertical direction), the workpiece may be translated along a second axis (e.g., mechanical scanning), where the vertical scan rate is significantly slower than the horizontal scan rate. In this example, the desired variable energy frequency is significantly higher than the fast scan frequency and may be approximately kHz or MHz (e.g., depending on the power supply selection). The present invention understands that it is generally necessary to perform a complete sweep of the energy range before the ion beam travels across the workpiece to its next epoch, such that all desired energy is deployed at every x and y position of the workpiece. For example, if the continuous movement of the workpiece relative to the ion beam is considered to be decomposed into individual quantized bits, then each position on the workpiece can be considered as a pixel.

[0049] The present invention thus provides all the energy required to span the entire workpiece implantation being scanned, thereby uniformly doping the entire workpiece with any number of different energies. For example, individual electrical bias signals control the acceleration / deceleration apparatus (e.g., also called an acceleration / deceleration apparatus) of the beam, and can also control the bending apparatus (e.g., also called a bending apparatus). For example, if the individual voltages are considered as pure triangular waveforms, a uniform dose can be provided at each of the energy steps along the waveform. The waveform can be further tuned to change the relative dose at different energy intervals along such a continuous spectrum. Thus, for example, the energy-induced waveform can change the relative concentration of energy spread or within a given scan.

[0050] To provide a general overview of the various concepts of the present invention, FIG1 illustrates an example of a system 100 for implanting ions having continuously controlled variable energies. According to one example, system 100 includes an ion source 102 configured to ionize doped material for generating an ion beam 104. A beamline assembly 106 is positioned downstream of the ion source 102, wherein the beamline assembly is configured to deliver the ion beam 104 toward a workpiece 108 positioned on a workpiece support 110 (e.g., a chuck) in a terminal station 112.

[0051] For example, an acceleration / deceleration stage 114 is further provided, configured to receive the ion beam during the delivery of the ion beam 104, and generate a continuously controlled variable energy ion beam 116 for implantation into a workpiece 108 selectively positioned within a terminal station 112. In one instance, one or more variable power sources 118, 120 (e.g., one or more power supplies) are operatively coupled to the acceleration / deceleration stage 114 and provide it with one or more electrical bias signals 122, 124 (e.g., voltage or current).

[0052] For example, one or more bias signals 122, 124 are applied to one or more electrodes 128 positioned above and below the ion beam 104 as it passes through the acceleration / deceleration stage 114. The acceleration / deceleration stage 114 may include, for example, one or more acceleration / deceleration electrodes 128 and one or more bending electrodes 126, 130, whereby the bias signal 122 applied to the acceleration / deceleration electrodes generates a continuously controlled variable energy ion beam 116, and the bias signal 124 applied to the bending electrodes generates continuous angle control of the ion beam 104. For example, one or more bias signals 122, 124 are further selectively changed via one or more waveform generators 132, 134, which are operatively coupled to one or more power supplies 118, 120 to provide thereto one or more waveforms 136, 138 (e.g., one or more time-varying signals). A controller 140 (e.g., a control system including one or more control devices) is further provided for selectively controlling one or more electrical bias signals 122, 124 via control of one or more power supplies 118, 120 and one or more waveform generators 132, 134. The controller 140 is further operable to control other configurations of the system 100, such as the workpiece support 110 and other components of the beamline assembly 106, such as beam scanning mechanisms, focusing and guiding elements, or other beam control components, as will be further discussed below.

[0053] In one example, a control and feedback signal 142 between the controller 140 and one or more power supplies 118, 120 and one or more waveform generators 132, 134 selectively controls and modulates the energy of the ion beam 104 to define a continuously controlled variable energy ion beam 116. For example, a bias signal 122 (e.g., a deceleration voltage) controlling the electrical bias supplied to the acceleration / deceleration electrode 128 can selectively change (increase and decrease) the energy of the ion beam 104 based on a waveform 136 provided from the waveform generator 132 to the power supply 118, thus defining a voltage difference associated with the acceleration / deceleration electrode. Similarly, a bias signal 124 controlling the electrical bias supplied to the bending electrode 130 can selectively bend the ion beam 104 upwards or downwards based on a waveform 138 provided from the waveform generator 134 to the power supply 120.

[0054] For example, the polarity of one or more bias signals 122, 124 can be switched when controlling the acceleration / deceleration and bending of the ion beam 104. For example, different energies can be achieved in the continuously controlled variable energy ion beam 116 when stepping through various voltages supplied to the bending electrode 130 and the acceleration / deceleration electrode 128. For example, each of the waveforms 136, 138 can be synchronized with a step of the mechanical scanning of the workpiece 108 (e.g., along the so-called slow scanning direction or x-axis), as will be discussed in more detail below. Similarly, when the energy of the continuously controlled variable energy ion beam changes, the bias signal 124 (e.g., bending voltage) applied to the bending electrode 130 can be changed to maintain a constant angular relationship between the continuously controlled variable energy ion beam 116 and the workpiece 108. Furthermore, the angular relationship between the continuously controlled variable energy ion beam 116 and the workpiece 108 can be changed as the energy of the continuously controlled variable energy ion beam is changed via the bias signal 124.

[0055] In another example, when the ion beam 104 is electrostatically or magnetically reciprocated (e.g., along the so-called fast scan direction or y-axis), one or more changing cycles of the bias signals 122, 124 on the accelerating / decelerating electrodes 128 and / or the bending electrodes 130 (e.g., based on one or more voltage changing cycles of one or more waveforms 136, 138) can be completed before or after the scanning direction of the ion beam is reversed. For example, a continuously controlled variable energy ion beam 116 can define an "energy scan" that is changed, cycled, or modulated via synchronization of the bias signals 122, 124 on the accelerating / decelerating electrodes 128 and / or the bending electrodes 130. For example, the energy scan is changed at a substantially higher frequency than the scan of the ion beam 104 in the fast scan direction.

[0056] Therefore, the bias signals 122, 124 supplied or provided to the acceleration / deceleration electrodes 126 and the bending electrodes 130 can be synchronized or otherwise controlled to provide a uniform distribution of energy achieved during placement in the workpiece 108. For example, the triangular waveform 145 shown in FIG2A can be considered as a single cycle of substantially smaller "steps" in energy change or modulation, and a uniform energy profile substantially similar to the triangular waveform can be achieved when the same amount of time is provided at each step. In the example shown in FIG2A, approximately 100 scans of energy within a predetermined range can be completed within each scan of the ion beam in a "rapid scanning" "step" of the ion beam across the surface of the workpiece or wafer.

[0057] If the time spent at each voltage is summed up, then for each individual time, each voltage is present in the waveform. Therefore, when multiple energies (e.g., 5 keV, 5.1 keV, 5.2 keV…24.9 keV, 25 keV) are applied according to the invention, each of the multiple energies is applied for the same amount of time from the lowest energy (e.g., 5 keV) to the highest energy (e.g., 25 keV). If a pure triangular waveform is not used, then, for example, the derivative of the waveform can be considered equal to the dwell time at a given voltage. For example, the waveform 150 shown in FIG2B illustrates that a longer time is spent at the higher energy, and a shorter time is spent at the lower energy before transitioning to the next energy due to reaching the maximum deceleration voltage (e.g., the lowest energy). For example, the application profile in a workpiece can therefore be designed to have a larger dose at the higher energies in that range than at the lower energies.

[0058] For example, the present invention provides the ability to implant any large number of different processing steps at different energies with different doses, all of which are nearly simultaneous with or in parallel with a single pass of an ion beam across the workpiece. For example, in a production environment, the number of implants in a conventional process may be limited (e.g., for production reasons, such as time or cost constraints) to implant three energies at three different doses in the same mask, and then rely on a subsequent annealing step to obtain a specific dopant profile on the workpiece. However, the present invention understands that a smoother profile of dopant concentration in the workpiece may be required to benefit the device formed on the workpiece. However, each time energy is added to a conventional processing flow, costs such as productivity losses are added. The present invention avoids this additional cost because it can provide any number and combination of energy and dose with virtually no added cost per processing step.

[0059] For example, the present invention can advantageously control the dopant concentration, angular distribution, and / or ion implantation depth (e.g., corresponding to the implantation energy) in the workpiece to correspond to the desired device characteristics provided by the implanted ions. For example, research and design (R&D) can use various models to develop specifications to obtain a desired R&D implantation profile that requires a specific dopant concentration at a given implantation depth, thereby requiring a large number of implantations in the workpiece (e.g., nine or ten implantations). However, in a production environment, due to various production issues (e.g., time and wafer handling, and the cost associated with each implantation), only a limited number of implantations can be performed on the workpiece (e.g., only two or three implantations). Therefore, instead of performing a large number of implantations to achieve the desired R&D implantation profile on the workpiece, various trade-offs are typically made to achieve an implantation profile that attempts to approximate the desired R&D implantation profile within the permitted limited number of implantations. However, the present invention advantageously provides the desired R&D implantation profile and dopant concentration without having to make such approximations and compromises.

[0060] Another illustrative waveform 160 according to the invention is illustrated in FIG. 2C, wherein the waveform comprises a plurality of steps of varying durations, thereby deploying a plurality of energies in a single cycle. The plurality of energies may be limited (e.g., three energies) such that the waveform can be described as having multiple generally flat segments interspersed with multiple steps in voltage. In a simple example, the three discrete energies may be achieved by a first long flat segment, a short step followed by another long flat segment, a short step, and then another long flat segment. In this example, all three energies can be deployed in a single deployment cycle. For example, the total dose may be set to 1.5e14, since all doses deployed with three energies are added together. Thus, all three energies can be deployed into the workpiece without removing the workpiece from the workpiece support and processing chamber or terminal station. Therefore, the workpiece is not exposed to atmospheric exposure between steps, and the workpiece is not subjected to workpiece handling hardware or handling steps that could induce misalignment and / or potentially catastrophic drop of the workpiece.

[0061] Furthermore, since the implantation energy level according to the invention is continuously swept, the mapper (e.g., a Faraday cup) can move substantially slower than the energy changes described herein, and the average flux of the ion beam, including all energies, can be measured at each location. Thus, the invention can be practiced with only an initial setup time to tune the ion implantation system for uniformity and angle, etc. Moreover, the invention can be implemented in systems incorporating acceleration or deceleration to achieve the final energy of the ion beam. For example, the polarity of the power supply for setting the final energy can be switched as needed to provide acceleration or deceleration.

[0062] Therefore, the present invention provides high-frequency, real-time control of the energy of ions implanted into the workpiece 108 of FIG. 1 by providing a time-varying signal (e.g., the final acceleration or deceleration of the ion beam 104 before implantation) on the voltage applied to the acceleration / deceleration stage 114, so as to produce a predetermined energy distribution across the workpiece 108. It should be noted that the time-varying signal associated with one or more waveforms 136, 138 may include any desired waveform that can be advantageously controlled to provide any desired energy profile across the workpiece 108.

[0063] For example, one or more waveform generators 132, 134 can be programmed to provide any desired waveform, such as a step, a series of step functions, a curve, or any desired form, even including randomized forms, wherein the waveform is controlled by a controller. Thus, a desired dopant concentration and / or energy profile can be provided, wherein the waveform can be designed to deliver the desired dopant concentration and / or energy profile at workpiece 108. Generally, in a waveform viewed on the xy-axis, where x is time and y is the voltage applied to the acceleration / deceleration stage 114, at any given time, the voltage will generate energy such that the voltage waveform defines the energy distribution. For example, the derivative of the energy distribution produces a relative dose per energy level. The percentage of time at a given voltage required for a given energy is determined as a proportion of the total implanted dose that will be achieved at that energy.

[0064] Figures 2A and 2B illustrate two waveforms 145 and 150 synchronized to control the acceleration or deceleration of the ion beam 104 via the acceleration / deceleration electrode 128 and the bending electrode 130. For example, the bending of the ion beam 104 is synchronized via a bias voltage signal 124 applied to the bending electrode 130 to maintain a constant angle of the ion beam 104 relative to the workpiece 108. For example, the bias voltage signals 122 and 124 to the acceleration / deceleration electrode 128 and the bending electrode 130 can therefore be synchronized by providing synchronization signals between individual waveform generators 132 and 134 or by a single waveform generator. Although not shown in the figures, the invention further encompasses, for example, implementing a waveform generator whereby the polarity of a single waveform generator can be split to provide individual desired bias voltages to the acceleration / deceleration electrode 128 and the bending electrodes 126 and 130.

[0065] Therefore, the controller 140 can control the bias signals 122 and 124 to the acceleration / deceleration electrodes 128 and the bending electrodes 126 and 130 in a predetermined manner to achieve a predetermined energy distribution at any given point on the workpiece 108. Alternatively, it should be understood that the invention can be implemented without bending of the ion beam 104, such that the controller 140 can control the bias signal 122 to the acceleration / deceleration electrodes 128 in a predetermined manner to achieve a predetermined energy distribution at any given point on the workpiece 108. According to another embodiment, the energy distribution does not change based on the position on the workpiece 108.

[0066] Therefore, the present invention is generally directed to a system, apparatus, and method for changing the energy of an ion beam in an ion implantation system. More specifically, the present invention is directed to a system, apparatus, and method for changing the energy of an ion beam when scanning an ion beam across a workpiece.

[0067] This invention is applicable to and covered in various ion implanter architectures. For example, the invention is applicable to at least three types of ion implanters: ion implanters in which a strip ion beam is defined and delivered along a beamline, the longitudinal dimension of the strip beam being larger than the width of the workpiece irradiated by the ion beam, and scanning the workpiece substantially transverse to the longitudinal dimension of the workpiece in front of the strip beam; ion implanters using an ion beam having a relatively static cross-sectional dimension (e.g., a pencil or dot beam) and in which the workpiece moves relative to the ion beam in two dimensions; and ion implanters using a hybrid system in which a pencil or dot beam oscillates or scans relative to the workpiece along a first direction to form a strip scanning beam, and moves the workpiece along a second direction transverse to the first direction to implant the entire workpiece.

[0068] Revised variable control of energy distribution in an ion implantation process has not been disclosed or covered to date, specifically, variable control of implantation energy across the surface of a target workpiece in a continuous manner. Therefore, the present invention provides a system, apparatus, and method for continuously changing the energy distribution of ions implanted by an ion beam across a workpiece.

[0069] It should be understood that the foregoing applications are only one of many procedures and applications implemented by the continuous and variable energy ion implantation system and method of the present invention. The scope of the disclosure and the claims is not limited to the solution to this problem, nor is it limited to the method for providing variable energy implantation of any shape or specific predetermined profile on a workpiece. In addition to discontinuous variable implantation depth profiles, the variable, continuous, non-uniform ion implantation method of the present invention can also be implemented in any way as needed to provide continuously variable implantation depth profiles. For example, the present invention is intended to be used in any desired application where it is necessary to change the ion implantation depth by selectively changing the ion implantation energy. There are several reasons for implantation at different energies (which translates to different ion implantation depths across the workpiece surface), including but not limited to: changes in the threshold voltage across the workpiece; systematic changes in the energy profile of implantation across the scan width of the workpiece; and the ability to implant multiple grains with different electrical properties on a single wafer.

[0070] Figure 3 illustrates an exemplary ion implantation system 200 in which the energy of the ion beam can be selectively altered and / or controlled as described herein. System 200 has a terminal unit 202, a beamline assembly 204, and a terminal station 206. Terminal unit 202 includes an ion source 208 powered by a high-voltage power supply 210, which generates an ion beam 212 and directs it to the beamline assembly 204. In this respect, ion source 208 generates charged ions extracted from the source via extraction assembly 214 and formed into the ion beam 212, which is then directed along a beam path in beamline assembly 204 to terminal station 206.

[0071] To generate ions, the dopant material to be ionized (not shown) is placed within the generation chamber 216 of the ion source 208. For example, the dopant material may be fed into the chamber 216 from a gas source (not shown). In one example, in addition to the power supply 210, it should be understood that any number of suitable mechanisms (not shown) may be used to excite free electrons within the ion generation chamber 216, such as RF or microwave excitation sources, electron beam injection sources, electromagnetic sources, and / or cathodes that generate arc discharges within the chamber. The excited electrons collide with dopant gas molecules, thereby generating ions. Generally, positive ions are generated, but herein, the invention is equally applicable to systems that generate negative ions.

[0072] Ions are controllably extracted via a slit 218 in a chamber 216 by an ion extraction assembly 214, which includes a plurality of extraction and / or suppression electrodes 220. For example, the ion extraction assembly 214 may include individual extraction power supplies (not shown) to bias the extraction and / or suppression electrodes 220, thereby accelerating the ions extracted by the chamber 216. It is understood that since the ion beam 212 contains particles with the same charge, the ion beam may tend to expand radially outward, or the beam may be "amplified," because particles with the same charge repel each other within the ion beam. It is also understood that this beam amplification phenomenon can be exacerbated in low-energy, high-current (e.g., high conductivity) beams, where many particles with the same charge move relatively slowly in the same direction, and where there is a large amount of repulsive force between the particles, but very little particle momentum to keep the particles moving in the direction of the beam path.

[0073] Therefore, the extraction assembly 214 is generally configured to extract the ion beam 212 at high energy so that the ion beam is not amplified (e.g., so that the particles have sufficient momentum to overcome the repulsive forces that could lead to beam amplification). Furthermore, it is generally advantageous to deliver the beam 212 at relatively high energy throughout the system, where this energy can be reduced as needed to promote beam containment only before the ions are implanted into the workpiece 222. It is also advantageous to generate and transport molecules or clusters of ions that can be transported at relatively high energy but implanted at lower equivalent energy, as the energy of the molecules or clusters is distributed among the doping atoms of the molecules.

[0074] In the exemplary ion implantation system depicted in Figure 3, the beamline assembly 204 includes a beam guide 224, a mass analyzer 226, a scanning system 228, a parallelizer 230, and one or more acceleration or deceleration and / or filtering subsystems 232. The mass analyzer 226 is configured to have approximately a 90-degree angle and includes one or more magnets (not shown) for establishing a (dipole) magnetic field therein. As the ion beam 212 enters the mass analyzer 226, the ion beam is correspondingly bent by the magnetic field, such that desired ions are transported along the beam path while ions with inappropriate charge-to-mass ratios are repelled. More specifically, ions with excessively large or small charge-to-mass ratios are deflected insufficiently or minimally to be directed into the sidewall 234 of the mass analyzer 226, allowing ions with the desired charge-to-mass ratio in the beam 212 to pass through here and exit via the analytical aperture 236.

[0075] Further description of the scanning system 228, wherein, for example, the scanning system includes a scanning element 238 and a focusing and / or guiding element 240. The scanning system 228 may include various known scanning mechanisms, such as those shown in U.S. Patent No. 4,980,562 to Berrian et al., U.S. Patent No. 5,091,655 to Dykstra et al., U.S. Patent No. 5,393,984 to Glanish, U.S. Patent No. 7,550,751 to Benveniste et al., and U.S. Patent No. 7,615,763 to Vanderberg et al., the entire contents of which are hereby incorporated by reference.

[0076] In the exemplary scanning system 228, respective power supplies 242, 244 are operatively coupled to the scanning element 238 and the focusing and guiding element 240, and more specifically, to the respective electrodes 238a, 238b and 240a, 240b located therein. The focusing and guiding element 240 receives a mass-analyzed ion beam 212 (e.g., a "pencil" or "dot" beam in the illustrated system 200) having a relatively narrow profile, wherein the voltage applied to plates 240a and 240b by the power supply 244 operates to focus and guide the ion beam to an optimal point on the scanning element 238, preferably the scanning vertex 246. The voltage waveform applied to the scanner plates 238a and 238b by the power supply 242 (e.g., power supply 244 can also act as power supply 242) then scans the beam 212 back and forth to expand the beam 212 outward into an elongated scanned or strip-shaped beam (e.g., scanned beam 212), which has a width or longitudinal dimension in the x-axis that is at least as wide as or wider than the workpiece of interest. It will be understood that the scan vertex 246 can be defined as a point in the optical path from which each small beam or scanned portion of the strip-shaped beam appears to originate after being scanned by the scanning element 238.

[0077] It should be understood that different types of scanning systems can be used for the type of ion implantation system described herein. For example, electrostatic or magnetic systems can be used in this invention. A typical specific example of an electrostatic scanning system includes a power supply coupled to scanner plates or electrodes 238a and 238b, wherein scanner 238 provides a scanning beam. Scanner 238 receives a mass-analyzed ion beam with a relatively narrow profile (e.g., a "pencil-shaped" beam in the illustrated system), and operates by a voltage waveform applied to scanner plates 238a and 238b by power supply 242 to scan the beam back and forth in the X direction (scanning direction) to cause the beam to expand outward into an elongated strip-shaped beam (e.g., a scanned beam), thereby having an effective X-direction width that is at least as wide as or wider than the workpiece of interest. Similarly, in a magnetic scanning system, a high current supply is connected to a coil of an electromagnet. The magnetic field is adjusted to scan the beam. For the purposes of this invention, all different types of scanning systems are contemplated, and the electrostatic systems described herein are for illustrative purposes only.

[0078] The scanned beam 212 then passes through a parallelizer 230. Various parallelizer systems 230 are illustrated in U.S. Patent Nos. 5,091,655 and 5,177,366 to Dykstra et al., 6,744,377 to Inoue, 7,112,809 to Rathmell et al., and 7,507,978 to Vanderberg et al., the entire contents of which are hereby incorporated by reference. As the name suggests, the parallelizer 230 deflects the incoming scanned pencil beam, which has scattering rays or fine beams, into parallel rays or fine beams 212a, so that the placement parameters (e.g., placement angles) are uniform across the workpiece 222. In the specific example described herein, the parallelizer 230 includes two dipole magnets 230a and 230b, wherein the dipoles are substantially trapezoidal and mirror-image of each other in orientation, thereby causing the beam 212 to bend into a substantially "S" shape. In a preferred embodiment, the dipoles have equal angles and opposite bending directions.

[0079] The primary purpose of the dipole is to convert the plurality of scattered rays or fine beams originating from the scanning vertex 246 into a plurality of substantially parallel rays or fine beams in the form of relatively thin, elongated band-shaped beams. As explained herein, the use of two symmetrical dipoles produces symmetry across the band-shaped beam with respect to the path length of the fine beams, as well as first-order and higher-order focusing properties. Furthermore, similar to the operation of the mass analyzer 226, an S-shaped bend is used to filter and decontaminate the ion beam 212. Specifically, the trajectories of neutral particles and / or other contaminants (e.g., environmental particles) entering the ion beam 212 downstream of the mass analyzer 226 are generally unaffected by the dipole (or minimally affected by the dipole), allowing these particles to continue along the original beam path. Thus, a relatively large number of these neutral particles are not bent or are bent very little, and therefore do not affect the workpiece 222 (e.g., the workpiece is positioned to receive the bent ion beam 212). It is understood that the removal of such contaminants by the ion beam 212 is important because these contaminants may possess incorrect charges and / or energies. Generally, such contaminants will be unaffected (or much less affected) by the deceleration and / or other stages in system 200. Therefore, they can have a significant (although undesirable and generally unacceptable) effect on the workpiece 222 in terms of dosage, energy, and angular uniformity. This, in turn, can result in unintended and undesirable device performance.

[0080] Downstream of the parallelization component 230, one or more deceleration stages 232 are provided. Examples of deceleration and / or acceleration systems are shown in U.S. Patent No. 5,091,655 to Dykstra et al., U.S. Patent No. 6,441,382 to Huang, and U.S. Patent No. 8,124,946 to Farley et al., the entire contents of which are hereby incorporated by reference. As previously indicated, up to this point in system 200, the beam 212 is typically delivered at a relatively high energy level to mitigate the tendency for beam amplification, which can be particularly high when the beam density is increased, for example, at the analytical aperture 236. Similar to the ion extraction assembly 214, the scanning element 238, and the focusing and guiding element 240, the deceleration stage 232 includes one or more electrodes 232a, 232b operable to decelerate the beam 212.

[0081] It will be understood that although two electrodes 220a and 220b, 238a and 238b, 240a and 240b, and 232a and 232b are described respectively in the exemplary ion extraction assembly 214, scanning element 238, focusing and guiding element 240, and deceleration stage 232, these elements 214, 238, 240, and 232 may include any suitable number of electrodes configured and biased to accelerate and / or decelerate ions and to focus, bend, deflect, converge, diverge, scan, parallelize, and / or decontaminate the ion beam 212, such as those provided in U.S. Patent No. 6,777,696 to Rathmell et al., the entire contents of which are hereby incorporated by reference. Additionally, the focusing and / or guiding element 240 may include electrostatic deflection plates (e.g., one or more pairs of electrostatic deflection plates) and a single lens, a quadrupole lens, and / or other focusing elements for focusing the ion beam. Although unnecessary, it is advantageous to apply voltage to the deflection plates within the guiding and focusing elements 240 so that the average value of these deflection plates is zero. This avoids the need to introduce an additional single lens to mitigate distortion in the focusing state of element 240. It should be understood that when the beam direction is proportional to the guiding voltage and length of the plates and inversely proportional to the beam energy, the "guiding" of the ion beam 212 varies particularly with the size of the plates 240a and 240b and the guiding voltage applied to them.

[0082] FIG4 illustrates an exemplary acceleration / deceleration stage 232 according to one or more embodiments of the present invention, more specifically as an electrode post 250, which includes a first electrode 254 and a second electrode 254 and a pair of intermediate electrode plates 256 and 258. The first electrode 252 and the second electrode 254 are substantially parallel to each other and define a first aperture 260 and a second aperture 262, respectively. A gap 264 is defined between apertures 260 and 262, and electrodes 252 and 254 are configured such that an axis 266 substantially orthogonal to the first electrode 252 and the second electrode 254 passes through the gap 264 and through the first aperture 260 and the second aperture 262. The intermediate electrode plates include an upper intermediate gap electrode 256 and a lower intermediate gap electrode 258. A first upper sub-gap region 268 is defined between the first electrode 252 and the upper intermediate gap electrode 256. A first lower sub-gap region 270 is defined between the first electrode 252 and the lower intermediate gap electrode 258. Similarly, a second upper sub-gap region 272 is defined between the second electrode 254 and the upper intermediate gap electrode 256, and a second lower sub-gap region 274 is defined between the second electrode 254 and the lower intermediate gap electrode 258. An ion beam 276 passes through the gap 264 and, for example, is deflected from the axis 266 by about 12 degrees, and is focused at a point 278 downstream of the gap 264. The invention is further incorporated herein by reference in its entirety from U.S. Patent No. 9,218,941, jointly owned by Jen et al.

[0083] In the illustrated example, a specific bias voltage is depicted to facilitate the operation of the electrode post 250 constituting the exemplary deceleration / acceleration stage 232. However, it should be understood that for the purposes of this invention, any suitable bias voltage can be applied between the electrodes to achieve the desired result (e.g., the degree of acceleration, deceleration, and / or deflection). In fact, in the context of this invention, where continuously controlled variable ion beam energy is the desired result, it should be understood that changes in the bias voltage signal applied to these electrodes will be essential, regardless of whether this involves changes in the voltage applied to the electrodes or the current passing through them. However, the bias voltage values ​​in Figure 4 effectively indicate the deceleration of the ion beam 276.

[0084] The ion beam 276, and more specifically the positive ions contained therein, enters the gap 264 through the first aperture 260 at an initial energy level (e.g., 6 keV in the illustrated example). To accelerate or decelerate the ions in the beam, the first electrode 252 and the second electrode 254 are biased in different ways, creating a potential difference between them, and the ions experience a corresponding increase or decrease in energy as they pass through the gap 264 between the first electrode 252 and the second electrode 254. For example, in the example shown in FIG4, the positive ions of the ion beam experience a 4 keV energy drop as they travel from the first electrode 252, which has a negative 4 kV bias, to the second electrode 254, which has a zero potential (e.g., coupled to ground). Therefore, when the ions pass through the gap 264 and experience a 4 keV energy drop, the original ion beam energy of positive 6 keV decreases to 2 keV. The ion beam 276 will therefore have a specific energy level (e.g., 2 KeV in the illustrated example) after it leaves the gap 264 and enters the neutral region downstream of the gap 264.

[0085] It should be understood that this situation is true regardless of the path that ions may take through gap 264. For example, in the illustrated example, ions entering the lower sub-gap 270 between the first electrode 252 and the lower intermediate gap electrode 258 will be accelerated at a rate greater than that of ions entering the upper sub-gap 268 between the first electrode 252 and the upper intermediate gap electrode 256. This is because the potential difference between the first electrode 252 and the lower intermediate gap electrode 258 is greater than the potential difference between the first electrode 252 and the upper intermediate gap electrode 256 (e.g., -2.5 KV (-4 KV minus -6.5 KV) for the lower sub-gap 270) and -0.5 KV (-4 KV minus -4.5 KV) for the upper sub-gap 268.

[0086] However, this difference in acceleration offsets the corresponding potential difference between the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258 and the second electrode 254. For example, in the illustrated example, the second electrode 254 is biased at zero (e.g., coupled to ground). Therefore, ions from the first lower sub-gap 270 decelerate more than ions from the first upper sub-gap 268. This compensates for the difference in acceleration of ions as they enter the gap, so that when the ions leave the gap, they all have substantially the same energy (e.g., 2 keV). Ions from the first lower sub-gap 270 will decelerate more significantly because they will have to cross a negative 6.5 kV (e.g., the negative 6.5 kV bias of the lower intermediate gap electrode 258 minus the zero V bias of the second electrode 254) when crossing the second lower sub-gap 274. In contrast, ions from the first upper sub-gap 268 will be slowed down to a lesser extent because they will only need to cross a negative 4.5 kV when crossing the second upper sub-gap 272 (e.g., the negative 4.5 kV bias of the upper intermediate gap electrode 614 minus the zero V bias of the second electrode 254). Therefore, regardless of the different paths taken by the ions and the energy levels through which the ions pass, all ions are essentially affected by the gaps at substantially the same energy level (e.g., 2 keV).

[0087] It should be understood that the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258 serve the dual purpose of drawing the ion beam into the gap 264 to accelerate or decelerate the ion beam and to provide beam deflection or bending for beam filtering purposes. For example, the intermediate gap plates 256 and 258 are typically biased differently relative to each other, thereby generating an electrostatic field therebetween to bend or deflect the beam upwards or downwards, or to have varying magnitudes depending on the magnitude of the bias voltage of the electrodes and the energy relative to the ion beam. In a characteristic example, the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258 are biased to -4.5 kV and -6.5 kV, respectively. Assuming the beam contains positively charged ions, this potential difference forces the positively charged ions passing through the gap 264 downwards toward the negatively charged lower intermediate gap electrode 258, ultimately causing the beam 276 to bend or deflect downwards (e.g., by about 12 degrees). Bending or deflecting ions in this manner has the following effects: filtering neutral particles from the beam that are unaffected by the electric field through which the ion beam passes; and filtering ions that may not be at substantially the same energy level as the ions to be implanted.

[0088] It should be understood that in order to maintain this exemplary 12-degree deflection of the beam in view of the energy change, the bias voltage applied to the intermediate gap electrodes 256, 258 must also be changed accordingly. For example, the acceleration of the ion beam can be induced by biasing electrodes 282, 284 to -4 kV while simultaneously biasing electrodes 252, 254 to +40 kV, but any bias voltage value is covered. This bias configuration creates a negative potential barrier extending into the intermediate region. It should be understood that with these bias voltages applied, the operation of the device is substantially similar to that described, except that the beam 276 is accelerated rather than decelerated. These exemplary values ​​are used to increase the energy level of the beam from, for example, 80 keV to 120 keV, thereby accelerating the beam by a factor of 1.5, wherein the positive ions in the beam 276 will be accelerated as the ions traverse the second upper sub-gap region 272 and the second lower sub-gap region 274.

[0089] It should be understood that the configuration, arrangement, and / or shaping of the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258 can be customized to facilitate control over the lensing, focusing, deflection, and / or acceleration / deceleration effects of the beam. As an example, in the illustration depicted in FIG4, the lower intermediate gap electrode 258 has a width that is slightly reduced relative to the width of the upper intermediate gap electrode 256, and also has a slightly inclined corner 280. These adjustments substantially counteract the enhanced lensing effect experienced by ions approaching the lower intermediate gap electrode 258 when they undergo stronger acceleration and / or deceleration due to the difference in the applied bias voltage. However, it should be understood that, for the purposes of this invention, these electrodes 256, 258 can have any suitable configuration, including the same shape. It should be further understood that, since the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258, which are primarily responsible for beam bending, operate substantially independently of the first electrode 252 and the second electrode 254, which are primarily responsible for accelerating / decelerating the beam 276, the beam may or may not be bent or deflected in acceleration, deceleration, and / or offset (e.g., zero acceleration / deceleration) modes. For example, the upper intermediate gap electrode and the lower intermediate gap electrode may be biased to the same voltage, so that acceleration or deceleration can be induced without bending the ion beam 276.

[0090] The overall net effect of all potential differences is the focusing, deceleration (or acceleration), and selective deflection of ions in beam 276. The deflection of the ion beam provides energy for decontamination because neutral particles in the beam continue along the original beam path parallel to axis 266, unaffected by the effects of the electrodes. For example, contaminants may then encounter certain types of barriers or absorption structures (not shown) that halt their forward progress and leave any workpiece unaffected by the contaminants. In contrast, the trajectory of the deflected ion beam 276 allows the beam to appropriately encounter and dope selected regions of the workpiece (not shown).

[0091] It should be understood that the electrode configuration (e.g., the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258 between the first electrode 252 and the second electrode 254) is also used to mitigate beam amplification, as this configuration minimizes the distance the beam 276 must travel before encountering the wafer. By accelerating, decelerating, or deflecting the beam 276 (e.g., by the upper intermediate gap electrode 256 and the lower intermediate gap electrode 258) while simultaneously focusing the beam (e.g., by the first electrode 252 and the second electrode 254), rather than cascading these bending and focusing stages, the terminal station can be positioned closer to the accelerator / decelerator stage of the ion implantation system.

[0092] In the illustrated example, a specific bias voltage is applied to the electrodes and is depicted to facilitate a better understanding of the operation of the deceleration stage 232 of FIG. 3. However, it should be understood that, for the purposes of this invention, any suitable voltage or current can be applied between the electrodes to achieve the desired result, such as the degree of acceleration, deceleration, and / or deflection (if present). Additionally, for the purposes of this invention, magnets and the current flowing through them can be used to achieve these desired results. Furthermore, the specific bias voltage is applied in a selective, continuously variable, and controlled manner to achieve the selective and variable energy control of this invention. However, the bias voltage value illustrated in FIG. 4 effectively indicates the deceleration of the ion beam 276.

[0093] It should be noted that the selective change of the bias voltage can be further based on one or more predetermined characteristics provided by one of the operators and the characteristic definition of workpiece 222, such as in FIG3, and can be iterative. For example, a "chaining" can be performed, in which a discrete number of chains with variable energies are provided to workpiece 222 in a predetermined sequence or in a randomized manner. For example, the predetermined sequence of chaining can start at a low energy and pass through a set of predetermined energies in a specific order from low to high energy. In another example, the predetermined sequence of chaining can start at a high energy and pass through a set of predetermined energies in a specific order from high to low energy. In yet another example, chaining can start at any given energy and pass through a set of predetermined energies in any specified or randomized order. For example, each "chain" can be predetermined by a metric mapping of workpiece 222 before being chained. Furthermore, each step of the chain can be programmed into the control system of the ion implanter as a series of sequential steps, and then the implantation chain can be started.

[0094] Therefore, the overall effect is a continuously controlled variable doping depth profile across workpiece 222, which may be uniform or non-uniform, thus defining the energy for patterned implantation. For example, chains of different energies can be executed repeatedly, wherein the dose and doping depth profile across the workpiece provided at each step of the chain produces a substantially uniform implantation profile. Alternatively, surface topography feedback can be used to selectively change the bias voltage during implantation and / or between chains or multiple chains of implantations.

[0095] It should be understood that different types of terminal stations 206 may be used in the implanter system 200. For example, a "batch" type terminal station may simultaneously support multiple workpieces 222 on a rotating support structure, wherein such workpieces 222 rotate through the path of the ion beam until all workpieces are fully implanted. On the other hand, a "tandem" type terminal station supports a single workpiece 222 along the beam path for implantation, wherein multiple workpieces 222 are implanted one at a time in a continuous manner, wherein each workpiece 222 is fully implanted before the implantation of the next workpiece 222 begins. In a hybrid system, the workpiece 222 may be mechanically translated in a first (Y or slow scan) direction while the beam is electrically or magnetically scanned in a second (X or fast scan) direction to impart the beam 212 over the entire workpiece 222, as disclosed, for example, in commonly assigned U.S. Patent 9,443,698, which is incorporated herein by reference in its entirety. In contrast, in a so-called two-dimensional mechanical scanning architecture known in the art and exemplified by the Optima HDTM ion implantation system manufactured and sold by Axcelis Technologies (Beverly, MA), the workpiece 222 can be mechanically translated in front of the ion beam at a fixed position in a first (slow) scanning direction, while simultaneously scanning the workpiece in a second substantially orthogonal (fast) scanning direction to impart the beam 212 over the entire workpiece 222. Alternatively, in a so-called strip beam system, the ion beam can be delivered along the beamline in such a way that the longitudinal dimension of the beam is larger than the workpiece, so that the workpiece is scanned only in a direction transverse to the longitudinal dimension of the beam to implant ions across the entire surface of the workpiece.

[0096] Terminal station 206, in the illustrated example, is a "continuous" type terminal station that supports a single workpiece 222 along the deployed beam path. A dosimetry system 286 may be further included in terminal station 206 near the workpiece location for calibration measurements prior to deployment. During calibration, beam 212 passes through dosimetry system 286. Dosimetry system 286 includes one or more plotters 288 that continuously traverse plotter path 290 to measure the profile of the scanned beam. Plotters 288 may include, for example, current density sensors, such as Faraday cups, that measure the current density of the scanned beam, where the current density varies with the deployment angle (e.g., the relative orientation between the beam and the mechanical surface of the workpiece and / or the relative orientation between the beam and the lattice structure of the workpiece). The current density sensors move in a generally orthogonal manner relative to the scanned beam and thus typically traverse the width of the strip-shaped beam. In one example, the dosimetry system measures both the beam density distribution and the angular distribution. The beam angle can be measured using a moving plotter that senses the current behind a shield with a slot, as described in the literature. After a short drift, the displacement of each individual fine beam from the slot position can be used to calculate the fine beam angle. It should be understood that this displacement can be considered a calibrated reference for beam diagnostics within the system.

[0097] The dosimetry system 286 is operatively coupled to the control system 292 to receive command signals from it and to provide it with measurement values. For example, the control system 292, which may include a computer, microprocessor, etc., is operable to obtain measurement values ​​from the dosimetry system 286 and to calculate the average angular distribution of the scanned strip beam across the workpiece. The control system 292 is also operatively coupled to the terminal unit 202 (from which the ion beam is generated) and the mass analyzer 226, scanning element 238 (e.g., via power supply 242), focusing and guiding element 240 (e.g., via power supply 244), parallelizer 230, and acceleration / deceleration stage 232 of the beamline assembly 204. Thus, any of these elements can be adjusted by the control system 292 to facilitate desired ion implantation parameters based on values ​​provided by the dosimetry system 286 or any other ion beam measurement or monitoring device. Control signals can also be generated via lookup tables stored in memory modules, typically based on empirical data collected through experiments.

[0098] As an example, an ion beam can first be established according to predetermined beam tuning parameters (e.g., stored / loaded into control system 292). Then, based on feedback from dosimetry system 286, scanner 238 can be adjusted to change the scanning speed of the scanned beam, thereby altering the ion dose on the workpiece. Similarly, acceleration / deceleration stage 232 and / or ion extraction assembly can be adjusted to change the beam energy level, thereby adjusting the junction depth by adjusting, for example, the bias voltage applied to the electrodes in ion extraction assembly 214 and / or deceleration stage 232. Correspondingly, for example, the strength and orientation of the magnetic or electric field generated in the scanner can be adjusted, for example, by adjusting the bias voltage applied to the scanning electrodes. The placement angle can be further controlled by adjusting, for example, the voltage applied to guide element 240 or acceleration / deceleration stage 232.

[0099] According to one embodiment of the invention, a control system 292 is provided, configured to establish a predetermined scanning pattern on a workpiece 222, wherein the workpiece is exposed to a point ion or pencil beam by means of a scanning system 228. For example, the control system 292 is configured to control various properties of the ion beam, such as the beam density and current of the ion beam, and other properties associated with the ion beam, specifically its energy. Additionally, the controller 292 is configured to control the scanning speed of the workpiece 222 positioned on a workpiece support 294. Although not shown in the figures, the workpiece support 294 is operatively coupled to, for example, a translation mechanism (e.g., a robotic device or other device), configured to translate the workpiece 222 residing on the workpiece support through the ion beam 212.

[0100] Furthermore, in the context of the present invention for providing a continuously controlled variable energy ion beam in the ion implantation system 200, the control system 292 is configured to modify and adjust the electrical bias signal 295 applied to various subsystems. For example, the control system 292 is configured to control the electrical bias signal 295 supplied to the deceleration / acceleration stage 232 by further controlling the supply of one or more waveforms 298 to one or more variable power supplies 299 or waveform generators 296, wherein the energy of the ion beam 212 in the ion implantation system is based on one or more waveforms applied to the various electrodes described herein.

[0101] Regarding the exemplary ion implantation system 200 described herein, the control system 292 can be configured to modify and change the scanning voltage applied to the scanner 228, and can be further configured to modify and change the bias voltage applied to the acceleration / deceleration stage 232 in sync with the scanning voltage based on the waveform, so as to adjust the energy and deflection of the ion beam accordingly. For example, this modification of the scanning voltage and bias voltage can be implemented in discrete steps or in a continuous manner (e.g., non-discrete) without removing the workpiece from the self-pressurizing plate or processing environment, thus providing various advantages over known systems and methods.

[0102] It should also be understood that the present invention can be combined with features known in this art to provide even greater variability in the ion implantation process during ion implantation. Features of the present invention for providing continuous variable energy control of the implantation process can be combined with other features for providing variable dose control of the ion implantation process to achieve variable energy and dose ion implantation on the surface of the wafer.

[0103] Similarly, it may be necessary to provide ions in different charge states to change the beam current at a given kinetic energy of the beam. The present invention for providing continuous variable energy control of the implantation process can be combined with features for providing variable charge states in the ion implantation process to achieve variable energy and / or variable dose ion implantation across the workpiece surface. Similarly, it may be necessary to provide the workpiece at temperatures below or above ambient temperature to achieve certain desired results. Therefore, the present invention for providing continuous variable energy control of the implantation process can be combined with features for providing low-temperature or high-temperature workpieces in the ion implantation process to achieve variable energy ion implantation across the wafer surface.

[0104] According to the present invention, the system described herein implements a method 300 for implanting ions at varying depths, as illustrated in FIG5. It should be noted that although illustrative methods are described and depicted herein as a series of actions or events, it will be understood that the present invention is not limited to the described order of such actions or events, as according to the present invention, some steps may occur in a different order and / or simultaneously with other steps besides those shown and described herein. Furthermore, not all described steps may be required to implement the method according to the present invention. Moreover, it should be understood that these methods can be implemented in conjunction with the systems described herein as well as with other systems not described herein.

[0105] Method 300 in Figure 5 begins at action 302 with providing a workpiece on a support. In action 304, an ion beam, such as a point ion beam, is provided, and in action 306, the ion beam is quality analyzed. In action 308, one or more of the workpiece and the ion beam may be scanned relative to each other. For example, in action 308, the workpiece is mechanically scanned in two orthogonal directions. In another alternative, the ion beam is electrostatically or magnetically scanned in a first direction and mechanically scanned in a second direction. In yet another alternative, the ion beam is electrostatically scanned in two non-parallel directions. In action 310, while scanning the ion beam across the workpiece, the energy of the ion beam is selectively changed in a predetermined waveform in a continuous manner, simultaneously with the scan in action 308. Therefore, the resulting implantation depth of the ions into the workpiece varies along the surface of the workpiece.

[0106] Therefore, the present invention relates to an ion implantation system and method for changing the energy of an ion beam as it travels across a workpiece (or vice versa). The invention achieves this by changing the electrical bias applied to the accelerating / decelerating electrodes, such that the ion energy delivered to the workpiece can be continuously varied to achieve a predetermined variable energy ion implantation depth at the workpiece based on a predetermined set of electrical bias signals provided to the accelerating / decelerating electrodes or the waveforms discussed above. In a preferred embodiment, the invention provides a continuously controlled variable energy pattern in response to a workpiece-crossing mapping and / or a continuous function mapped to a matrix that can be used to program the beam energy according to the position across the workpiece. For example, the invention can be carried out by generating a spatial mapping in memory, where each cell of the memory location corresponds to a unique energy relative to the x and y positions on the workpiece. It should be understood that the invention can be incorporated into systems for providing variable energy implantation in the form of a continuously variable energy form or in the form of a step function change in energy or other forms. The change in the energy profile across the workpiece surface can be symmetrical, and can also occur in quadrants or in other ways, such as the X1 energy in a specified location Q1, the X2 energy in Q2, etc.

[0107] For illustrative purposes, the exemplary ion implantation system architecture described herein is particularly well-suited for achieving continuous variation of the ion beam energy across the surface of a workpiece, wherein the system 200 of Figure 3 incorporates a scanning spot beam that scans across the surface of the workpiece electronically or magnetically. This scanning of the spot beam allows for modulation or alteration of the ion beam energy during scanning. Thus, when the scanning beam strikes a selected location on the wafer, the beam passes through all its optical elements along the beamline, wherein the beam can be modified to change its energy to a selected energy before striking the wafer. Advantageously, the change of beam energy can be synchronized with the x and y scanning functions of the scanner and / or terminal station, so that the energy of the scanned beam can be varied according to x and y. Advantageously, in the exemplary ion implantation system described herein, the final beam energy can be varied by applying a bias voltage to a single downstream component, the deceleration / acceleration stage 232. This eliminates the laborious and complex tuning requirements of modifying the electrical bias in upstream components that can alter ion energy, such as the extraction electrode 214 immediately downstream of the ion source 208, but which in turn affects the bias of other downstream components to maintain the desired integrity and characteristics of the beam. Furthermore, the bias voltage applied to the forced acceleration / deceleration and its deflection energy filter state can be varied according to the x and y positions of the scanned beam, allowing the beam to be constrained to travel along the same path to the wafer independently of changes in ion beam energy.

[0108] It should be understood that all selective biases of components and subsystems can be implemented via control system 292, and via feedback loop input to the acceleration / deceleration stage and the energy filter based on the position of the beam output from the self-scanning system. However, it should be understood that the feedback loop is not required to achieve the continuously controlled variable energy ion implantation feature of the present invention, because a pre-programmed ion beam energy profile can also be advantageously implemented to perform the selective variable energy ion implantation of the present invention. Thus, the ion beam energy can be selectively changed for each die or other feature or region via feedback loops at the x, y coordinate positions of the beam on the wafer or via a predetermined desired pattern.

[0109] The continuously controlled variable energy ion implantation of the present invention can also be implemented via a workpiece pattern, wherein the continuous and controlled change of one or more voltages supplied to one or more electrodes in the electrode posts and / or energy filters is based on a workpiece pattern positioned on a workpiece support. In another alternative, the ion implantation system of the present invention may include detectors (e.g., optical detectors, cameras, etc.), or multiple detectors configured to detect one or more properties of the workpiece located on the workpiece support, wherein the continuous change of one or more voltages supplied to one or more electrode posts in the acceleration / deceleration stages and / or energy filters is further based on feedback from the detectors. According to this alternative specific example, the detectors may preferably be configured to detect one or more of the following: the thickness of the workpiece, the thickness of the layer disposed on the workpiece, the grain pattern on the workpiece, the edge of the workpiece, the center of the workpiece, or a predefined area on the workpiece, wherein the detected information is provided as input to continuously change the energy of the ion beam.

[0110] Although the invention has been described with respect to one or more embodiments, it should be understood that changes and / or modifications may be made to the described examples without departing from the spirit and scope of the appended claims. In particular, with respect to the various functions performed by the aforementioned components or structures (blocks, units, engines, assemblies, devices, circuits, systems, etc.), unless otherwise indicated, the terminology used to describe such components (including references to "component") is intended to correspond to any component or structure that performs the specified function of the described component (e.g., functionally equivalent), even if the disclosed structure is not structurally equivalent to the function performed in the exemplary embodiments of the invention described herein. Furthermore, although specific features may have been disclosed with respect to only one of several embodiments, such features may be combined with one or more other features of other embodiments when desired and advantageous for any given or specific application. Furthermore, in terms of the extent to which the terms "including / includes," "having / has / with," or variations thereof are used in the implementation methods or the scope of the patent application, such terms are intended to be inclusive in a manner similar to the term "comprising." [Simplified Explanation of the Diagram]

[0021] [Figure 1] is a block diagram of a portion of the ion implantation of several states according to the present invention.

[0022] [Figure 2A] is a graph illustrating the uniform distribution of ion dose according to energy in an example state according to one embodiment of the present invention.

[0023] [Figure 2B] is a graph illustrating the derivative of voltage adjustment according to one embodiment of the present invention.

[0024] [Figure 2C] is a graph illustrating another voltage adjustment according to one embodiment of the present invention.

[0025] [Figure 3] is a schematic block diagram of an example ion implantation system of several states according to the present invention.

[0026] [Figure 4] illustrates a portion of an ion beam in an ion implantation system of several forms according to the present invention.

[0027] [Figure 5] illustrates various methods for optimizing the implantation of ions into a workpiece according to the present invention.

Claims

1. An ion implantation system comprising: an ion source configured to ionize a doped material and generate an ion beam; a beamline assembly positioned downstream of the ion source and configured to deliver the ion beam toward a workpiece; a scanning device configured to scan one or more of the ion beam and the workpiece relative to each other along a first scanning axis; an acceleration / deceleration stage configured to receive the ion beam during delivery; and a terminal station positioned downstream of the acceleration / deceleration stage, wherein the terminal station includes a workpiece support configured to selectively position the workpiece in one path of the ion beam. One or more power supplies operatively coupled to and configured to provide one or more electrical bias signals to the acceleration / deceleration stage, wherein the acceleration / deceleration stage is configured to define a plurality of energies of the ion beam based on the one or more electrical bias signals; and a controller configured to selectively change the one or more electrical bias signals provided to the acceleration / deceleration stage while scanning the ion beam and one or more of the workpiece along the first scanning axis, wherein the selective change of the one or more electrical bias signals is at least partially based on the position of the ion beam relative to one of the workpieces and across one of the predetermined implantation profiles of the workpieces, wherein the implantation depth of the ions into one of the workpieces is changed during the scanning.

2. The ion implantation system of claim 1, wherein the selective change of the one or more electrical bias signals is further based at least in part on a waveform applied to one or more electrical bias signals, and wherein the predetermined implantation profile is generally defined by the waveform.

3. The ion implantation system of claim 2, further comprising a waveform generator configured to generate the waveform.

4. The ion implantation system of claim 3, wherein the waveform generator is operatively coupled to the one or more power supplies and configured to selectively apply the waveform to generate the one or more electrical bias signals.

5. The ion implantation system of claim 3, wherein the waveform generator is operatively coupled to the controller and configured to continuously change the one or more electrical bias signals supplied to the acceleration / deceleration stage while scanning the ion beam and one or more of the workpiece along the first scanning axis.

6. The ion implantation system of claim 1, wherein the scanning device is configured to scan the ion beam and one or more of the workpiece reciprocally relative to each other along the first scanning axis at a first scanning frequency, and wherein the controller is configured to selectively change the one or more electrical bias signals at a bias change frequency greater than the first scanning frequency.

7. The ion implantation system of claim 6, wherein the bias change frequency is at least one order of magnitude greater than the first scan frequency.

8. The ion implantation system of claim 1, wherein the scanning device is further configured to scan one or more of the ion beam and the workpiece support relative to each other along a second scanning axis that is not parallel to the first scanning axis.

9. The ion implantation system of claim 8, wherein the scanning device includes one or more of an electrostatic scanner and a magnetic scanner, the electrostatic scanner and the magnetic scanner being configured to scan the ion beam electrostatically and magnetically, respectively, at least along the first scanning axis.

10. The ion implantation system of claim 9, wherein the scanning device further comprises a mechanical scanning device configured to mechanically scan one of the workpiece supports along the second scanning axis.

11. The ion implantation system of claim 8, wherein the first scanning axis is orthogonal to the second scanning axis.

12. The ion implantation system of claim 8, wherein the scanning device includes a mechanical scanning device configured to mechanically scan the workpiece support along the first scanning axis and the second scanning axis.

13. The ion implantation system of claim 1, wherein the one or more power sources include one or more selective variable power supplies, and wherein the one or more bias signals include one or more of a voltage and a current.

14. The ion implantation system of claim 1, wherein the selective change of the one or more electrical bias signals is further based on one or more predetermined characteristics provided by an operator and one of the characteristics defined by the workpiece.

15. The ion implantation system of claim 1, wherein the predetermined implantation profile includes a predetermined dopant energy distribution across the entire workpiece.

16. The ion implantation system of claim 1, wherein the selective change of the one or more electrical bias signals is further based on feedback from the scanning device corresponding to the position of the ion beam relative to the workpiece.

17. The ion implantation system of claim 1, wherein the selective change of the one or more electrical bias signals comprises a predetermined sequence of one of the plurality of electrical bias signals.

18. The ion implantation system of claim 1, wherein the selective change of the one or more bias signals is randomized.

19. The ion implantation system of claim 1, wherein the acceleration / deceleration stage includes an electrode post having one or more electrode pairs, and wherein the one or more bias signals are supplied to the one or more electrode pairs of the electrode post.

20. The ion implantation system of claim 19, wherein the electrode post includes one or more of an ion beam accelerator, an ion beam decelerator, and a curved electrode.

21. The ion implantation system of claim 1, wherein the selective change of the one or more electrical bias signals will provide a uniform dose of ions within a predetermined energy range to the entire workpiece.

22. The ion implantation system of claim 1, further comprising a detector configured to detect one or more workpiece attributes associated with the workpiece positioned on the workpiece support, wherein the selective change of the one or more electrical bias signals is further based on feedback from the detector.

23. The ion implantation system of claim 22, wherein the detector includes an optical detector, and wherein the one or more workpiece attributes include one or more of the following: a thickness of the workpiece, a thickness of a layer disposed on the workpiece, a grain pattern on the workpiece, an edge of the workpiece, a center of the workpiece, and a predefined area on the workpiece.

24. The ion implantation system of claim 1, further comprising an energy filter including at least one bent electrode, wherein at least one of the one or more power sources is further operatively coupled to and configured to provide at least one of the one or more electrical bias signals thereto, and wherein the at least one bent electrode is configured to deflect the ion beam according to the one or more electrical bias signals provided to the acceleration / deceleration stage.

25. The ion implantation system of claim 1, wherein the controller is further configured to control one or more of the ion source, the beamline assembly, the scanning device, the acceleration / deceleration stage, and the terminal station based on a plurality of implantation recipes.

26. The ion implantation system of claim 25, wherein the controller is further configured to select one of the plurality of implantation formulations based at least in part on the position of the ion beam relative to the workpiece and across the predetermined implantation profile of the workpiece.

27. A method for ion implantation, the method comprising: directing an ion beam to a workpiece; scanning one or more of the ion beam and the workpiece relative to each other, thereby implanting ions into the workpiece; and selectively changing the energy of one of the ion beams while scanning the one or more of the ion beams and the workpieces, at least in part based on a position of the ion beam relative to one of the workpieces and across a predetermined implantation profile of one of the workpieces, wherein the implantation depth of the ions into one of the workpieces is changed during the scanning.

28. The method of claim 27, wherein selectively changing the energy of the ion beam comprises changing the bias voltage of an electrode located along a path of the ion beam based on a waveform.

29. The method of claim 28, wherein the change in the bias voltage to the electrode defines one of the final energies of the plasma at the workpiece.

30. The method of claim 28, wherein the electrode comprises one or more of an ion beam accelerator electrode, an ion beam decelerator electrode, and a bent electrode.

31. The method of claim 30, wherein selectively changing the energy of the ion beam further comprises changing the bias voltage to the bent electrode, wherein the bent electrode is configured to deflect the ion beam in an angle, and wherein the change in the bias voltage to the bent electrode is synchronized with the change in the bias voltage to the ion beam accelerator electrode or the ion beam decelerator electrode.

32. The method of claim 27 further includes defining the predetermined planting profile across the entire surface of one of the workpieces.

33. The method of claim 27, further comprising pre-tuning one or more components of the ion beam for a plurality of formulations for the ion implantation to the workpiece before scanning the ion beam and the workpiece relative to each other.

34. The method of claim 27, further comprising pre-tuning one or more components of the ion beam according to a plurality of formulations for implanting ions into the workpiece before scanning the ion beam and the workpiece relative to each other.

35. An ion implantation system comprising: an ion source configured to generate an ion beam; an acceleration / deceleration stage configured to receive the ion beam to generate a final ion beam having one of its associated final energies; a workpiece support configured to selectively position a workpiece along one path of the final ion beam; a scanning device configured to scan one or more of the ion beam and the workpiece support relative to each other along a first scanning axis and a second scanning axis; and one or more power supplies operatively coupled to the acceleration / deceleration stage and configured to provide one or more electrical bias signals thereto. A waveform generator operatively coupled to one or more of the power sources and configured to controllably apply a waveform to the one or more bias signals; and a controller operatively coupled to the power sources and the waveform generator and configured to selectively change the one or more bias signals supplied to the acceleration / deceleration stage while scanning the ion beam and one or more of the workpiece support, to implant a plurality of energies of the ion beam into the workpiece in a predetermined manner, wherein the selective change of the one or more bias signals supplied to the acceleration / deceleration stage is at least partially based on the waveform, the position of the ion beam relative to one of the workpieces, a predetermined energy of the ions implanted into the workpiece, and a predetermined implantation profile across one of the workpieces, wherein the implantation depth of the ions into one of the workpieces is changed during the scanning.

36. The ion implantation system of claim 35, wherein the controller is configured to control the waveform generator to provide the predetermined energy of ions implanted across the workpiece.

37. The ion implantation system of claim 35, wherein the scanning device is configured to scan the ion beam along the first scanning axis at a first frequency, and wherein the scanning device is further configured to scan the workpiece along the second scanning axis at a second frequency, wherein the first frequency is at least an order of magnitude greater than the second frequency.

38. The ion implantation system of claim 37, wherein the selective change of the one or more electrical bias signals supplied to the acceleration / deceleration stage is selectively changed at a third frequency, wherein the third frequency is at least an order of magnitude greater than the first frequency.

39. The ion implantation system of claim 35, wherein one or more of the ion source, the acceleration / deceleration stage, the workpiece support, the scanning device, the one or more power supplies, and the waveform generator are pre-tuned for a plurality of implantation formulations.

40. The ion implantation system of claim 39, wherein the controller is further configured to select one of the plurality of implantation formulations based at least in part on the waveform, the position of the ion beam relative to the workpiece, and the predetermined energy of the ions implanted across the workpiece.

41. An ion implantation system comprising: an ion source configured to form an ion beam and guide the ion beam to a workpiece; one or more beamline assemblies configured to deliver the ion beam along a beam path; a scanner device configured to selectively and repeatedly scan one or more of the ion beam and the workpiece along a first scanning axis; an acceleration / deceleration stage downstream of the scanner device; a power supply configured to provide a bias signal to the acceleration / deceleration stage; and a controller configured to change the bias signal provided from the power supply to the acceleration / deceleration stage, at least in part, based on a predetermined implantation profile across one of the workpieces, while repeatedly scanning the ion beam and one or more of the workpieces along the first scanning axis, thereby selectively changing the final energy of one of the ions implanted into the workpiece along the first scanning axis, wherein the implantation depth of the ions into one of the workpieces is changed simultaneously with the scanning.

42. The ion implantation system of claim 41, wherein the controller is further configured to control one or more of the ion source, the one or more beamline assemblies, the scanner device, and the acceleration / deceleration stage based on a plurality of implantation recipes.

43. The ion implantation system of claim 41, wherein the scanner device is further configured to selectively traverse one or more of the ion beam and the workpiece along a second scan axis that is substantially perpendicular to the first scan axis.

44. The ion implantation system of claim 43, wherein the scanner device is configured to repeatedly traverse the ion beam along the first scanning axis at a first frequency and traverse the workpiece along the second scanning axis at a second frequency, wherein the first frequency is at least an order of magnitude greater than the second frequency.

45. The ion implantation system of claim 44, wherein the bias voltage signal provided to the acceleration / deceleration stage is varied at a third frequency, wherein the third frequency is greater than the first frequency.

46. ​​The ion implantation system of claim 41, wherein the electrical bias signal provided to the acceleration / deceleration stage is changed in a predetermined manner.

47. The ion implantation system of claim 46, wherein the electrical bias signal provided to the acceleration / deceleration stage is altered to provide uniform implantation of one of a plurality of energies across one surface of the workpiece.

48. The ion implantation system of claim 46, wherein the electrical bias signal provided to the acceleration / deceleration stage is altered to provide a predetermined pattern of one of a plurality of energies across one surface of the workpiece.

49. An ion implantation system comprising: a power supply configured to provide an electrical bias signal corresponding to a predetermined waveform; and an energy conversion component configured to receive the electrical bias signal to selectively convert an ion beam to a final energy based on the predetermined waveform and a predetermined implantation profile across a workpiece, wherein the final energy is selectively convertible and simultaneously converts the implantation depth of ions into one of the workpieces.

50. The ion implantation system of claim 49, further comprising a controller configured to selectively change one of the predetermined waveforms.

51. The ion implantation system of claim 49, further comprising an ion beam scanner configured to scan the ion beam along a first scan axis, wherein the bias signal corresponding to the predetermined waveform is supplied to the energy changing component while scanning the ion beam along the first scan axis.

52. The ion implantation system of claim 51 further includes a workpiece scanner configured to selectively scan the workpiece relative to the ion beam along a second scanning axis, wherein a frequency at which the ion beam is scanned along the first scanning axis is greater than a frequency at which the workpiece is scanned along the second scanning axis.

53. The ion implantation system of claim 52, wherein one of the frequencies of the predetermined waveform is greater than the frequency at which the ion beam is scanned along the first scanning axis.

54. The ion implantation system of claim 52, wherein the energy alteration component includes an acceleration / deceleration stage and a bending electrode, wherein the bending electrode is configured to change one path of the ion beam based on an electrical bias signal corresponding to the predetermined waveform supplied to the acceleration / deceleration stage.

55. The ion implantation system of claim 54, wherein the predetermined waveform is synchronized with one or more of the ion beam scanner and the workpiece scanner.

56. The ion implantation system of claim 54 further includes a controller configured with a plurality of tuning formulas for modifying the characteristics of the ion beam, wherein at least the acceleration / deceleration stage responds to the plurality of tuning formulas for ion implantation.

57. The ion implantation system of claim 56, wherein the controller is further configured to select one of the plurality of tuned formulations based at least in part on the predetermined waveform and the position of the ion beam relative to one of the workpieces.

58. The ion implantation system of claim 57, wherein the controller is further configured to select one of the plurality of tuning formulations based at least in part on the predetermined waveform, the position of the ion beam relative to the workpiece, and a predetermined energy of one of the ions implanted across the workpiece.

59. The ion implantation system of claim 49, wherein the energy alteration component includes one or more of an accelerating electrode, a decelerating electrode, and an angle energy filter.

60. The ion implantation system of claim 49, further comprising a scanning mechanism for scanning the ion beam along a first axis, wherein the bias voltage signal corresponding to the predetermined waveform is synchronized with the scanning mechanism.

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