Ion implantation system and method for gas transport for ion implantation

Abstract

An ion implantation system and a method for gas transportation for ion implantation. The ion implantation system includes an ion implanter having an ion source unit and a dopant source gas supply system. The system includes a dopant source gas storage tank located inside a gas box container away from the ion implanter, and a dopant source gas supply pipe for supplying the dopant source gas from the dopant source gas storage tank to the ion source unit. The dopant source gas supply pipe includes an inner tube, an outer tube surrounding the inner tube, a first tube adapter connected to the first ends of the corresponding inner tube and outer tube, and a second tube adapter connected to the second ends of the corresponding inner tube and outer tube. The first tube adapter connects the inner tube to the dopant source gas storage tank, and the second tube adapter connects the inner tube to the ion source unit.

Description

Technical Field

[0001] The present disclosure relates to a gas delivery system and method for an ion implanter. Background Art

[0002] Ion implantation is the process of introducing chemical species into a substrate by directly bombarding the substrate with energetic ions. In semiconductor manufacturing, ion implantation is often used to introduce dopants into semiconductor wafers to change the electronic properties of the semiconductor wafer. Ion implantation is performed in an ion implanter. The ion implanter includes an ion source unit for generating positively charged ion species. These ion species are extracted from the ion source unit by a high voltage extraction potential and then filtered to obtain the desired ion species (i.e., the ion species that will impact the target material (e.g., the target area on the semiconductor wafer)). The desired ion species are further accelerated and directed to the target material for implantation. Summary of the invention

[0003] According to some embodiments of the present disclosure, an ion implantation system is provided, comprising: an ion implanter and a dopant source gas supply system. The ion implanter comprises an ion source unit. The dopant source gas supply system comprises: a dopant source gas storage tank and a dopant source gas supply pipe. The dopant source gas storage tank is in a gas box container far away from the ion implanter. The dopant source gas supply pipe is used to supply the dopant source gas from the dopant source gas storage tank to the ion source unit, and the dopant source gas supply pipe comprises: an inner tube, an outer tube, a first tube adapter and a second tube adapter. The outer tube surrounds the inner tube. The first tube adapter is connected to the first end of each of the inner tube and the outer tube, and the first tube adapter connects the inner tube to the dopant source gas storage tank. The second tube adapter is connected to the second end of each of the inner tube and the outer tube, and the second end is opposite to the first end, and the second tube adapter connects the inner tube to the ion source unit.

[0004] According to some embodiments of the present disclosure, an ion implantation system is provided, comprising: an ion implanter, a dopant source gas storage tank, a dopant source gas supply pipe and a pressure sensor. The ion implanter is inside a housing, and the ion implanter includes an ion source unit. The dopant source gas storage tank is located in a gas box container outside the housing. The dopant source gas supply pipe is used to supply the dopant source gas from the dopant source gas storage tank to the ion source unit, and the dopant source gas supply pipe includes: an inner tube, an outer tube, a first tube adapter and a second tube adapter. The inner tube is used to transport the dopant source gas. The outer tube surrounds the inner tube and is used to transport an inert gas. The first tube adapter is connected to a first end of each of the inner tube and the outer tube, and the first tube adapter connects the inner tube to the dopant source gas storage tank. The second tube adapter is connected to a second end of each of the inner tube and the outer tube, wherein the second end is opposite to the first end, and the second tube adapter connects the inner tube to the ion source unit. The pressure sensor is used to measure the pressure level of the inert gas in the outer tube.

[0005] According to some embodiments of the present disclosure, a gas transport method for ion implantation is provided, comprising: filling an outer tube of a dopant source gas supply tube with an inert gas having a predetermined pressure; supplying the dopant source gas from a dopant source gas storage tank via an inner tube of the dopant source gas supply tube surrounded by the outer tube to an ion source unit of an ion implanter, wherein the ion implanter is arranged in a shell, and the dopant source gas storage tank is arranged in a gas box container located outside the shell; monitoring the pressure of the inert gas in situ; and determining a leak in the dopant source gas supply tube if the pressure of the inert gas is lower than a predetermined threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] When read in conjunction with the accompanying drawings, various aspects of the present disclosure can be best understood from the following detailed description. It should be understood that, in accordance with standard practice in the industry, various features are not drawn to scale. In fact, for clarity of discussion, the size of the various features may be arbitrarily increased or reduced.

[0007] Figure 1 is a schematic diagram of an ion implantation system according to some embodiments;

[0008] Figure 2A is a perspective view of a dopant source gas supply tube used in a dopant source gas supply system in an ion implantation system according to some embodiments;

[0009] Figure 2B is along Figure 2A A cross-sectional view of the dopant source supply tube taken along line BB';

[0010] Figure 3 is a flow chart of a method for delivering a dopant source gas to an ion implanter of an ion implantation system according to some embodiments;

[0011] Figure 4 is a block diagram of a control unit for controlling the operation of an ion implantation system.

[0012]

Explanation of symbols

[0013] 100:Ion implantation system

[0014] 102: Ion implanter

[0015] 104: Dopant source gas supply system

[0016] 106: Monitoring System

[0017] 108: Control unit

[0018] 110: Shell

[0019] 120: ion source unit

[0020] 122: Mass analyzer unit

[0021] 124: Ion Acceleration Unit

[0022] 126: Terminal Station

[0023] 128: Ion Beam

[0024] 130:Air box container

[0025] 132: Dopant source gas storage tank

[0026] 132a: Dopant source gas storage tank

[0027] 132b: Dopant source gas storage tank

[0028] 132c: Dopant source gas storage tank

[0029] 134: Stop valve

[0030] 134a: Stop valve

[0031] 134b: Stop valve

[0032] 134c: Stop valve

[0033] 140: Dopant source gas supply pipe

[0034] 141: Control box

[0035] 142: Pipeline body

[0036] 144: Inner tube

[0037] 146: External pipe

[0038] 148: Groove

[0039] 150a: Tube adapter

[0040] 150b: Tube adapter

[0041] 152a: Inner cover

[0042] 152b: Inner cover

[0043] 154a: Outer cover

[0044] 154b: Outer cover

[0045] 155a: First gap

[0046] 155b: Second gap

[0047] 156a: Entrance

[0048] 156b: Exit

[0049] 158:Entrance

[0050] 160: Inert gas pipeline

[0051] 162: Conductive gas transmission line

[0052] 164:Pressure sensor

[0053] 166: Ammeter

[0054] 220: Mass analyzer unit

[0055] 300: Methods

[0056] 302: Operation

[0057] 304: Operation

[0058] 306: Operation

[0059] 308: Operation

[0060] 310: Operation

[0061] 312: Operation

[0062] 402: Processor

[0063] 404: Computer readable storage medium

[0064] 406: Instruction

[0065] 408: Bus

[0066] 410: Input / output interface

[0067] 412: Network interface

[0068] 414: Network

[0069] 416: Pressure sensor parameters

[0070] B-B': Line DETAILED DESCRIPTION

[0071] The following disclosure provides many different embodiments or examples for realizing the different features of the provided subject matter. In order to simplify this disclosure, the specific examples of elements, values, operations, materials, configurations, etc. are described below. Of course, these are only examples and are not intended to be limiting. Other elements, values, operations, materials, configurations, etc. can be expected. For example, in the following description, forming a first feature on or above a second feature can include an embodiment in which the first feature and the second feature are formed with direct contact, and can also include an embodiment in which additional features are formed between the first feature and the second feature so that the first feature and the second feature may not directly contact. In addition, this disclosure can repeat reference numbers and / or words in various examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or configurations discussed.

[0072] Furthermore, spatially relative terms (e.g., "below," "beneath," "below," "above," "on," and other related terms) are used herein to simply describe the relationship of an element or feature as shown in the figures to another element or feature. During use or operation, these spatially relative terms encompass different orientations of the device in addition to the orientation shown in the figures. Furthermore, the devices may be rotated (90 degrees or other angles), and the spatially relative descriptors used herein may be interpreted accordingly.

[0073] Typical dopant species used in ion implantation to manufacture silicon-based integrated circuits include boron as a p-type dopant and phosphorus or arsenic as an n-type dopant. The dopant species are generated by dopant source gases such as boron fluoride (BF3), phosphine (PH3), and arsine (AsH3). These dopant source gases are highly toxic, and in order to protect factory personnel from these toxic gases, gas cylinders used to supply dopant source gases are usually placed in a gas box. The gas box is set inside the housing where the ion implanter is located. The gas box is a housing that is connected to the ion source unit when the ion implanter is in operation and has the same high voltage as the ion source unit.

[0074] Due to the limited space inside the housing of the ion implanter, small gas cylinders must be used. Gas cylinders containing toxic / hazardous dopant source gases must be frequently changed and replaced with fresh cylinders filled with dopant source gases. To perform such cylinder changes inside the gas box, a technician must wear a self-contained breathing apparatus (SCBA) device, manually remove the used gas cylinder from the gas box, and install a fresh gas cylinder in the gas box. Therefore, significant safety issues arise when handling these dopant source gas cylinders.

[0075] In addition to the hazards associated with replacing gas cylinders within the housing of an ion implanter, gas cylinders often become depleted during processing, necessitating the ion implanter system be shut down to perform cylinder replacements. Such unplanned downtime of the ion implanter results in expensive rework of some of the processed wafers, and in some cases, the wafers may be defective or even unusable due to the interruption of processing of those wafers.

[0076] In an embodiment of the present disclosure, an ion implantation system is provided, which includes a dopant source gas supply system, which is used to supply one or more dopant source gases to the ion implanter from a location away from the ion implanter. Placing the dopant source gas supply system outside the housing in which the ion implanter is placed helps to reduce the footprint of the ion implanter. In addition, placing the dopant source gas supply system outside the housing in which the ion implanter is placed allows the use of larger gas storage tanks, which can reduce the frequency of replacing empty gas storage tanks whose gas has been completely consumed. Therefore, the operating efficiency of the ion implantation system is improved. The ion implantation system also includes a monitoring system, which is used to in-situ monitor the leakage of dopant source gas from a dopant source gas supply tube, which is used to couple the dopant source gas storage tank to the ion source unit. Therefore, in the event of a dopant source gas leak, the ion implantation system provides enhanced safety.

[0077] Figure 1 is a schematic diagram of an ion implantation system 100 according to some embodiments. Figure 1 The ion implantation system 100 includes an ion implanter 102 for performing an ion implantation process on a semiconductor wafer, a dopant source gas supply system 104 for supplying one or more dopant source gases to the ion implanter 102, and a monitoring system 106 for in-situ monitoring of leakage of the dopant source gases during the ion implantation process. The ion implantation system 100 is communicatively coupled to a control unit 108. The elements of the ion implantation system 100 receive control signals from the control unit 108 and perform various operations based on the received control signals.

[0078] The ion implanter 102 is disposed in a housing 110. In some embodiments, the ion implanter 102 includes an ion source unit 120, a mass analyzer unit 122, an ion acceleration unit 124, and an end station 126. The ion implanter 102 is configured to generate an ion beam 128, transmit the ion beam 128 toward the end station 126, and impact the ion beam 128 on a workpiece (e.g., a semiconductor wafer) in the end station 126.

[0079] The ion source unit 120 is used to ionize the dopant source gas to form ions. The ion source unit 120 generates ions by introducing electrons into a vacuum arc chamber filled with the dopant source gas. The collision of the electrons with the atoms and molecules in the dopant source gas results in the formation of an ionized plasma composed of positive ions and negative ions. The generated ions are extracted from the ion source unit 120 by applying a high voltage to form an ion beam 128. In order to generate the ion beam 128, the ion source unit 120 is maintained at a high positive potential to generate ions and extract the generated ions. In some embodiments, the ion source unit 120 is at a potential such as from about 5 kilovolts (kV) to up to about 250 kV relative to the ground potential. In some embodiments, the ion source unit 120 is at a potential of 90 kV relative to the ground potential.

[0080] The mass analyzer unit 122 is positioned along the ion beam path between the ion source unit 120 and the end station 126. The mass analyzer unit 122 has a curved internal passage and one or more magnets disposed along the internal passage of the mass analyzer unit 122. When the ion beam 128 enters the internal passage of the mass analyzer unit 220, the ion beam 128 is bent by the magnetic field of the magnet. Therefore, ions in the ion beam 128 having a charge-to-mass ratio outside a predetermined range are deflected into the sidewalls of the internal passage, while selected ions in the ion beam 128 having a charge-to-mass ratio within a predetermined range are allowed to leave the mass analyzer unit 122.

[0081] The ion acceleration unit 124 is used to apply an acceleration voltage to the ion beam 128 after the ion beam 128 leaves the mass analyzer unit 122, so as to achieve a desired implantation energy before the ion beam 128 reaches the terminal station 126. In an embodiment, the acceleration voltage is adjusted within a range of about 50 kV to about 250 kV.

[0082] The terminal station 126 is located at the end of the ion beam path. The terminal station 126 is used to receive the ion beam 128 and direct the ion beam 128 to the semiconductor wafer. In some embodiments, the terminal station 126 includes a chuck (not shown) for holding the semiconductor wafer thereon, and an actuator (not shown) for moving the chuck with the semiconductor wafer thereon in one or more directions. The movement of the chuck can cause the ion beam 128 to impact the semiconductor wafer in a uniform manner. In some embodiments, the terminal station 126 includes a transfer chamber (load lock) for moving the semiconductor wafer into or out of the ion implanter 102, and a robot arm for transferring the semiconductor wafer between the chuck and the transfer chamber. In some embodiments, the terminal station 126 also includes a measurement device for measuring one or more characteristics of the ion beam 128 to be impacted on the semiconductor wafer, thereby providing feedback information to adjust the ion beam 128 according to the process recipe to be used on the semiconductor wafer. Examples of measured ion beam characteristics include, but are not limited to, ion beam profile, ion beam energy, and ion beam current.

[0083] The dopant source gas supply system 104 can supply different types of dopant source gases to the ion source unit 120 of the ion implanter 102 in a parallel type manner to facilitate easy switching between dopant source gases (e.g., allowing easy switching from an n-type dopant to a p-type dopant). For example, for n-type dopants, gaseous hydrides such as arsine (AsH3) or phosphine (PH3) are commonly used as dopant source gases, while for p-type dopants, gaseous fluorides such as boron difluoride are commonly used as dopant source gases. All of these dopant source gases are toxic and corrosive and require appropriate handling.

[0084] In some embodiments, the dopant source gas supply system 104 originates from a source remote from the ion implanter 102. In some embodiments, the source is a sealed gas box container 130 that houses a plurality of dopant source gas storage tanks 132. The dopant source gas storage tanks 132 are used to store different types of dopant source gases and supply the different types of dopant source gases to the ion source unit 120 of the ion implanter 102. For the safety of factory personnel, the gas box container 130 and the dopant source gas storage tanks 132 disposed therein are maintained at a ground potential (e.g., 0 volts) or a low potential during operation of the ion implantation system 100.

[0085] In some embodiments, the dopant source gas storage tank 132 includes a first dopant source gas storage tank 132a for supplying a first dopant source gas to the ion source unit 120 of the ion implanter 102, a second dopant source gas storage tank 132b for supplying a second dopant source gas to the ion source unit 120 of the ion implanter 102, and a third dopant source gas storage tank 132c for supplying a third dopant source gas to the ion source unit 120 of the ion implanter 102. It should be understood that although Figure 1 The dopant source gas supply system 104 is illustrated as a delivery system that can provide three (3) different types of dopant source gases, however, the scope of the present disclosure also includes systems that provide more or fewer dopant source gases. In some embodiments, the first dopant source gas is an arsenic-containing gas such as arsine (AsH3), the second dopant source gas is a phosphorus-containing gas such as phosphine (PH3), and the third dopant source gas is a boron-containing gas such as boron fluoride (BF3).

[0086] The stop valve 134 is connected to the corresponding dopant source gas storage tank 132 (e.g., 132a, 132b, 132c) to control the supply of the dopant source gas from the corresponding dopant source gas storage tank 132 (e.g., 132a, 132b, 132c) to the ion source unit 120 of the ion implanter 102. For example, in some embodiments, the first stop valve 134a is connected to the first dopant source gas storage tank 132a to control the supply of the first dopant source gas from the first dopant source gas storage tank 132a to the ion source unit 120 of the ion implanter 102; the second stop valve 134b is connected to the second dopant source gas storage tank 132b to control the supply of the second dopant source gas from the second dopant source gas storage tank 132b to the ion source unit 120 of the ion implanter 102; and the third stop valve 134c is connected to the third dopant source gas storage tank 132c to control the supply of the third dopant source gas from the third dopant source gas storage tank 132c to the ion source unit 120 of the ion implanter 102. Each stop valve 134 (e.g., 134a, 134b, and 134c) is normally closed, but each stop valve 134 (e.g., 134a, 134b, and 134c) is opened when the ion implantation system 100 is in operation and when the corresponding dopant source gas is supplied to the ion source unit 120 of the ion implanter 102.

[0087] The dopant source gas supply system 104 further includes a plurality of dopant source gas supply pipes 140 for delivering dopant source gas from respective dopant source gas storage tanks 132 (e.g., 132a, 132b, and 132c) to the ion source unit 120. Because each dopant source gas supply pipe 140 has a similar configuration and operates in a similar manner, it will be described in detail for the sake of brevity. Figure 1 Only one dopant source gas supply pipe 140 is shown in the figure, which couples the dopant source gas storage tank 132a to the ion source unit 120. In some embodiments, the dopant source gas supply pipe 140 starts from the outside of the gas box container 130 and ends at the control box 141 located inside the housing 110. In some embodiments, the control box 141 includes a mass flow controller (not shown) to control the amount of dopant source gas flowing into the ion source unit 120 of the ion implanter 102. The dopant source gas supply pipe 140 thus spans the potential difference between the gas box container 130 and the ion source unit 120 of the ion implanter 102. In some embodiments, there is a 90 kV potential difference between the opposite ends of the dopant source gas supply pipe 140.

[0088] Figure 2A and Figure 2B Draw Figure 1 The dopant source gas supply pipe 140 is provided. Figure 2A is a perspective view of a dopant source gas supply tube 140 according to some embodiments. Figure 2B is along Figure 2A FIG. 1 is a cross-sectional view of the dopant source gas supply pipe 140 taken along line BB′. Figure 2A and Figure 2B In some embodiments, the dopant source gas supply pipe 140 includes a pipe body 142 and pipe adapters ( 150 a , 150 b ) connected to opposite ends of the pipe body 142 .

[0089] In some embodiments, the pipe body 142 has a double-walled pipe structure. The pipe body 142 includes two separate pipes, wherein the inner pipe 144 conveys the dopant source gas from the dopant source gas storage tank 132 (e.g., 132a, 132b, or 132c), and the outer pipe 146 conveys an inert gas such as nitrogen or argon. The outer pipe 146 surrounds the inner pipe 144, and the diameter of the outer pipe 146 is greater than the diameter of the inner pipe 144. In some embodiments, the inner pipe 144 and the outer pipe 146 have a circular shape. However, it should be understood that the inner pipe 144 and the outer pipe 146 can have any shape (e.g., hexagonal and elliptical).

[0090] In some embodiments, the outer tube 146 is filled with an inert gas having a predetermined pressure, and the pressure change of the inert gas inside the outer tube 146 is monitored. Therefore, when the pressure change of the inert gas in the outer tube 146 is lower than a predetermined threshold, the leakage of the dopant source gas supply tube 140 can be detected. In addition, the pressure of the inert gas in the outer tube 146 is maintained higher than the pressure of the dopant source gas in the inner tube 144. Therefore, if any leakage related to the inner tube 144 occurs, the dopant source gas will be controlled in the inner tube 144. Therefore, in the event of a leak in the inner tube 144, the outer tube 146 can serve as a safe containment body.

[0091] When the ion implantation system 100 is in operation, the dopant source gas is delivered to the ion source unit 120 through the dopant source gas supply pipe 140. Within the housing 110 of the ion implanter 102, the dopant source gas is raised from the ground potential to the potential at which the ion source unit 120 operates. In some embodiments, the ion source unit 120 operates at 90 kV. Therefore, the dopant source gas supply pipe 140 must cross the potential difference in order to transport the dopant source gas from the dopant source gas storage tank 132 (e.g., 132a, 132b, or 132c) to the ion source unit 120. In order to electrically insulate the ion source unit 120 from the electrical ground of the gas box container 130, the inner pipe 144 and the outer pipe 146 of the pipe body 142 are made of an electrically insulating material (e.g., polytetrafluoroethylene (PTFE), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC) or a ceramic material (e.g., alumina)). The insulating tube material helps maintain a potential difference between the dopant source gas storage tank 132 (eg, 132 a , 132 b , or 132 c ) and the ion source unit 120 during operation of the ion implantation system 100 .

[0092] In some embodiments, in order to provide sufficient mechanical strength to the pipe body 142, grooves 148 are formed on the outer surface of each of the inner tube 144 and the outer tube 146 of the pipe body 142. In some embodiments, these grooves 148 are formed along the outer circumference of each of the inner tube 144 and the outer tube 146 of the pipe body 142.

[0093] The first tube adapter 150a and the second tube adapter 150b are connected to the front end and the rear end of the pipeline body 142, respectively. The first tube adapter 150a is used to seal the front end of the pipeline body 142 and connect the front end of the pipeline body 142 to the dopant source gas storage tank 132 (for example, 132a, 132b or 132c). In some embodiments, the first tube adapter 150a includes an inner cover 152a for connecting to the front end of the inner tube 144 of the pipeline body 142 and an outer cover 154a for connecting to the front end of the outer tube 146 of the pipeline body 142. There is a gap 155a between the inner cover 152a and the outer cover 154a. In some embodiments, the first tube adapter 150a further includes an inlet end 156a, which extends through the outer cover 154a and the inner cover 152a to be fluidically connected to the inner tube 144 of the pipeline body 142. The inlet end 156a is used to allow the dopant source gas from the dopant source gas storage tank 132 (e.g., 132a, 132b, or 132c) to flow into the inner tube 144 of the pipe body 142. The first pipe adapter 150a also includes an inlet end 158 that extends through the outer cover 154a to fluidly communicate with the outer tube 146 of the pipe body 142. The inlet end 158 is used to allow an inert gas to be pumped into the outer tube 146 of the pipe body 142 via, for example, an inert gas line 160.

[0094] The second tube adapter 150b is used to seal the rear end of the pipe body 142 and connect the rear end of the pipe body 142 to the ion source unit 120 of the ion implanter 102. In some embodiments, the second tube adapter 150b includes an inner cover 152b connected to the rear end of the inner tube 144 of the pipe body 142 and an outer cover 154b connected to the rear end of the outer tube 146 of the pipe body 142. A gap 155b is provided between the inner cover 152b and the outer cover 154b. In some embodiments, the second tube adapter 150b includes an outlet end 156b, which extends through the outer cover 154b and the inner cover 152b to be fluidically connected to the inner tube 144 of the pipe body 142. The outlet end 156b is used to allow the dopant source gas flowing into the inner tube 144 of the pipe body 142 to flow out of the dopant source gas supply pipe 140 and flow into the ion source unit 120 of the ion implanter 102.

[0095] The second tube adapter 150b is maintained at a higher potential than the first tube adapter 150a because the second tube adapter 150b is connected to a conductive gas transmission line 162, which is coupled to the ion source unit 120 of the ion implanter 102. In some embodiments, the first tube adapter 150a and the second tube adapter 150b are made of a conductive material such as stainless steel.

[0096] The monitoring system 106 is used to monitor the dopant source gas supply tube 140 for leaks in situ. In some embodiments, the monitoring system 106 includes a pressure sensor 164 fluidly connected to the inert gas line 160. The pressure sensor 164 is used to detect the pressure level of the inert gas contained in the outer tube 146 of the dopant source gas supply tube 140 at any time during the operation of the ion implantation system 100. By monitoring the pressure level of the inert gas in the outer tube 146, if the pressure of the inert gas decreases (for example, if the pressure of the inert gas drops below a predetermined threshold), a leak is detected. Upon detecting that the inert gas pressure drops below the predetermined threshold, the control unit 108 sends a control signal to close the corresponding stop valve 134 (for example, 134a, 134b, or 134c), thereby closing the corresponding dopant source gas storage tank 132 (for example, 132a, 132b, or 132c). Therefore, a safety problem caused by the release of toxic dopant source gas into the atmosphere due to leakage of the dopant source gas supply pipe 140 may be prevented.

[0097] In some embodiments, the monitoring system 106 further includes an ammeter 166 installed between the dopant source gas supply pipe 140 and the ground. The ammeter 166 is used to detect a current signal. In normal operation of the ion implantation system 100, the current detected by the ammeter 166 is zero or under background noise. When a condition such as arc or discharge occurs due to a leak in the dopant source gas supply pipe 140, the ammeter 166 can detect the current signal and trigger the control unit 108 to close the corresponding stop valve 134 (e.g., 134a, 134b, or 134c). The ammeter 166 is optional and can be omitted in some embodiments of the present disclosure.

[0098] Figure 3 According to some embodiments, the dopant source gas is delivered to Figure 1 Flowchart of method 300 for ion implanter 102 of ion implantation system 100. One or more components of ion implantation system 100 are controlled by control unit 108 ( Figure 4 ) controls to execute method 300.

[0099] The method 300 includes operation 302 , in which the outer tube 146 of the dopant source gas supply tube 140 is filled with an inert gas (eg, nitrogen) having a predetermined pressure.

[0100] In operation 304 of the method 300, dopant source gas is supplied from the dopant source gas storage tanks 132 (e.g., 132a, 132b, 132c) to the ion source unit 120 of the ion implanter 102. The dopant source gas at the ground potential from the dopant source gas storage tanks 132 is delivered to the ion source unit 120 of the ion implanter 102 operating at a higher potential (e.g., about 90 kV) via the inner tube 144 of the dopant source gas supply tube 140.

[0101] In operation 306 of method 300 , the pressure of the inert gas contained in the outer tube 146 of the dopant source gas supply tube 140 is monitored using the pressure sensor 164 as the dopant source gas flows out of the dopant source gas storage tank 132 to the ion source unit 120 of the ion implanter 102 .

[0102] In operation 308 of method 300, it is determined whether the dopant source gas supply tube 140 is leaking. In the event of a leak in the dopant source gas supply tube 140, the pressure level of the inert gas in the outer tube 146 of the dopant source gas supply tube 140 is reduced. The pressure value of the inert gas in the outer tube 146 of the dopant source gas supply tube 140 is sent to the control unit 108 and compared with a predetermined pressure threshold. Once the pressure of the inert gas drops below the predetermined pressure threshold, an alarm is triggered to report a leak in the dopant source gas supply tube 140. Otherwise, the dopant source gas will continue to be delivered to the ion source unit 120 of the ion implanter 102 through the dopant source gas supply tube 140.

[0103] If it is determined that there is a leak associated with the dopant source gas supply pipe 140, the method 300 proceeds to operation 310. In operation 310, in response to an alarm indicating that a leak has occurred in the dopant source gas supply pipe 140, the supply of the dopant source gas is interrupted. For example, once the control unit 108 determines that the dopant source gas supply pipe 140 is leaking, the control unit 108 sends a control signal to the corresponding stop valve 134 (e.g., 134a, 134b, or 134c). The corresponding stop valve 134 (e.g., 134a, 134b, or 134c) is closed to prevent gas from flowing from the corresponding dopant source gas storage tank 132 (e.g., 132a, 132b, or 132c) to the ion source unit 120 of the ion implanter 102.

[0104] In operation 312 , factory personnel are notified, and the damaged dopant source gas supply pipe 140 is replaced.

[0105] Figure 4 is a block diagram of a control unit 108 for controlling the operation of the ion implantation system 100 according to some embodiments.

[0106] In some embodiments, the control unit 108 is a general purpose computer device that includes a hardware processor 402 and a non-transitory computer readable storage medium 404 encoded (i.e., stored) with computer program code (i.e., a set of executable instructions 406). The computer readable storage medium 404 is also encoded with instructions 406 to interface with components of the ion implantation system 100 (e.g., the ion implanter 102 and the dopant source gas supply system 104). The processor 402 is electrically connected to the computer readable storage medium 404 via a bus 408. The processor 402 is also electrically connected to an input / output (I / O) interface 410 via the bus 408. A network interface 412 is also electrically connected to the processor 402 via the bus 408. The network interface 412 is connected to a network 414 to enable the processor 402 and the computer readable storage medium 404 to connect to external components via the network 414. The processor 402 is configured to execute computer program instructions 406 encoded in a computer-readable storage medium 404 , so that the control unit 108 can be used to perform some or all of the operations described in the method 300 .

[0107] In some embodiments, the processor 402 is a central processing unit (CPU), a multi-processor, a distributed processing system, an application specific integrated circuit (ASIC), and / or a suitable processing unit.

[0108] In some embodiments, the computer-readable storage medium 404 may be an electronic, magnetic, optical, electromagnetic, infrared, and / or semiconductor system (or device or apparatus). For example, the computer-readable storage medium 404 includes semiconductor or solid-state memory, magnetic tape, portable computer disk, random access memory (RAM), read-only memory (ROM), rigid disk, and / or optical disk. In some embodiments using optical disks, the computer-readable storage medium 404 includes compact disk-read only memory (CD-ROM), compact disk-read / write (CD-R / W), and / or digital video disc (DVD).

[0109] In some embodiments, the computer-readable storage medium 404 stores computer program instructions 406 that are used to cause the control unit 108 to perform a portion or all of the method 300. In some embodiments, the computer-readable storage medium 404 also stores information required to perform the method 300 and information generated during the performance of the method 300 (e.g., pressure sensor parameters 416 and / or a set of executable instructions for performing one or more operations of the method 300).

[0110] In some embodiments, the computer readable storage medium 404 stores computer program instructions 406 for interfacing with the ion implanter system 100. The computer program instructions 406 enable the processor 402 to generate operating instruction readable elements in the ion implanter 102, the dopant source gas supply system 104, and the monitoring system 106 to effectively implement the operations described with respect to the ion implanter 102, the dopant source gas supply system 104, and the monitoring system 106.

[0111] The control unit 108 includes an input / output interface 410. The input / output interface 410 is coupled to external circuits. In some embodiments, the input / output interface 410 includes a keyboard, a keypad, a mouse, a trackball, a touchpad, and / or cursor direction keys for communicating information and commands to the processor 402.

[0112] The control unit 108 also includes a network interface 412 coupled to the processor 402. The network interface 412 allows the control unit 108 to communicate with a network 414 that connects one or more other computer systems. The network interface 412 includes a wireless network interface (e.g., Bluetooth, Wi-Fi, WIMAX, GPRS, or WCDMA); or a wired network interface (e.g., Ethernet, USB, or IEEE-131212). In some embodiments, the operations described with respect to the method 300 are implemented in two or more control units 108, and information such as the intensity of the refracted light and one or more threshold intensity values ​​is exchanged between different control units 108 via the network 414.

[0113] The benefits and features of the present disclosure will become more apparent through the following examples:

[0114] One aspect of the present disclosure relates to an ion implantation system. In some embodiments, the ion implantation system includes an ion implanter including an ion source unit and a dopant source gas supply system. The dopant source gas supply system includes a dopant source gas storage tank and a dopant source gas supply pipe, wherein the dopant source gas storage tank is located in a gas box container away from the ion implanter, and the dopant source gas supply pipe is used to supply the dopant source gas from the dopant source gas storage tank to the ion source unit. The dopant source gas supply pipe includes an inner tube, an outer tube surrounding the inner tube, a first tube adapter connected to a first end of each of the inner tube and the outer tube, and a second tube adapter connected to a second end of each of the inner tube and the outer tube opposite to the first end. The first tube adapter connects the inner tube to the dopant source gas storage tank, and the second tube adapter connects the inner tube to the ion source unit. In some embodiments, each of the inner tube and the outer tube includes an electrically insulating material. In some embodiments, each of the inner tube and the outer tube includes polytetrafluoroethylene, polypropylene, polyethylene, or polyvinyl chloride. In some embodiments, each of the first tube adapter and the second tube adapter includes a conductive material. In some embodiments, each of the first tube adapter and the second tube adapter includes stainless steel. In some embodiments, the first tube adapter includes an inner cover that seals the first end of the inner tube and an outer cover that seals the first end of the outer tube. In some embodiments, the first tube adapter also includes a first port that is fluidly connected to the inner tube and a second port that is fluidly connected to the outer tube. In some embodiments, the first port extends through the inner cover and the outer cover of the first tube adapter, and the second port extends through the outer cover of the first tube adapter. In some embodiments, the second tube adapter includes an inner cover that seals the second end of the inner tube and an outer cover that seals the second end of the outer tube. In some embodiments, the second tube adapter also includes a third port that is fluidly connected to the inner tube. In some embodiments, the third port extends through the inner cover and the outer cover of the second tube adapter.

[0115] Another aspect of the present disclosure relates to an ion implantation system. In some embodiments, the ion implantation system includes an ion implanter located inside a housing and including an ion source unit. The ion implantation system also includes a dopant source gas storage tank located inside a gas box container outside the housing. The ion implantation system also includes a dopant source gas supply pipe, which is used to supply the dopant source gas from the dopant source gas storage tank to the ion source unit. The dopant source gas supply pipe includes: an inner pipe, which is used to transport the dopant source gas; an outer pipe, which surrounds the inner pipe and is used to transport an inert gas; a first pipe adapter, which is connected to a first end of each of the inner pipe and the outer pipe and connects the inner pipe to the dopant source gas storage tank; and a second pipe adapter, which is connected to a second end of each of the inner pipe and the outer pipe (the second end is opposite to the first end) and connects the inner pipe to the ion source unit. The ion implantation system also includes a pressure sensor, which is used to measure the pressure level of the inert gas in the outer pipe. In some embodiments, each of the inner pipe and the outer pipe includes an electrically insulating material. In some embodiments, the first tube adapter includes an inner cover that seals the first end of the inner tube, an outer cover that seals the first end of the outer tube, a first inlet end that extends through the inner cover and the outer cover to fluidly communicate with the inner tube, and a second inlet end that extends through the outer cover to fluidly communicate with the outer tube. In some embodiments, the second tube adapter includes an inner cover that seals the second end of the inner tube, an outer cover that seals the second end of the outer tube, and an outlet end that extends through the inner cover and the outer cover to fluidly communicate with the inner tube. In some embodiments, each of the first tube adapter and the second tube adapter includes stainless steel. In some embodiments, each of the inner tube and the outer tube includes a plurality of grooves on an outer surface thereof. In some embodiments, the gas box container is at ground potential.

[0116] Another aspect of the present disclosure relates to a method for using an ion implantation system. In some embodiments, a method includes filling an outer tube of a dopant source gas supply tube with an inert gas having a predetermined pressure. The method also includes supplying a dopant source gas from a dopant source gas storage tank to an ion source unit of an ion implanter via an inner tube of the dopant source gas supply tube surrounded by the outer tube. The ion implanter is configured in a housing, and the dopant source gas storage tank is configured in a gas box container located outside the housing. The method also includes in-situ monitoring of the pressure of the inert gas. The method also includes determining a leak in the dopant source gas supply tube if the pressure of the inert gas is below a predetermined threshold. In some embodiments, the method also includes stopping the supply of the dopant source gas by closing a stop valve connected to the dopant source gas storage tank.

[0117] The features of several embodiments are summarized above so that those with ordinary knowledge in the art can better understand the various aspects of the present disclosure. Those with ordinary knowledge in the art should understand that they can easily use the present disclosure as a basis for designing or modifying other processes and structures to achieve the same purposes and / or achieve the same benefits as the embodiments described herein. Those with ordinary knowledge in the art should also understand that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and they can be variously changed, replaced and modified without departing from the spirit and scope of the present disclosure.

Claims

1. An ion implantation system, characterized in that: Include: An ion implanter includes an ion source unit; and A dopant source gas supply system comprising: a doping source gas storage tank in a gas box container away from the ion implanter; and a dopant source gas supply pipe, for supplying a dopant source gas from the dopant source gas storage tank to the ion source unit, the dopant source gas supply pipe comprising: an inner tube; an outer tube surrounding the inner tube; a first tube adapter connected to a first end of each of the inner tube and the outer tube to connect the inner tube to the dopant source gas storage tank, the first tube adapter comprising a first inner cover and a first outer cover, the first outer cover being separated from the first inner cover by a first gap, a size of the first inner cover being larger than a size of the first end of the inner tube to enclose the first end of the inner tube within the first inner cover, and a size of the first outer cover being larger than a size of the first end of the outer tube to enclose the first end of the outer tube within the first outer cover; and a second tube adapter connected to a second end of each of the inner tube and the outer tube to connect the inner tube to the ion source unit through the second tube adapter, the second tube adapter comprising a second inner cover and a second outer cover, the second outer cover being separated from the second inner cover by a second gap, a size of the second inner cover being larger than a size of the second end of the inner tube so as to enclose the second end of the inner tube in the second inner cover, and a size of the second outer cover being larger than a size of the second end of the outer tube so as to enclose the second end of the outer tube in the second outer cover.

2. The ion implantation system according to claim 1, characterized in that: Each of the inner tube and the outer tube includes an electrically insulating material.

3. The ion implantation system according to claim 2, characterized in that: Each of the inner tube and the outer tube includes polytetrafluoroethylene, polypropylene, polyethylene, or polyvinyl chloride.

4. The ion implantation system according to claim 1, characterized in that: Each of the first tube adapter and the second tube adapter includes a conductive material.

5. The ion implantation system according to claim 4, characterized in that: Each of the first tube adapter and the second tube adapter comprises stainless steel.

6. The ion implantation system according to claim 1, characterized in that: Further included is a monitoring system configured to in-situ monitor a leakage of the dopant source gas supply pipe, wherein the monitoring system includes a pressure sensor and an ammeter, the pressure sensor is used to measure a pressure level of the inert gas in the outer tube, and the ammeter is installed in the dopant source gas supply pipe to detect a leakage current.

7. The ion implantation system according to claim 1, characterized in that: The first tube adapter also includes a first port in fluid communication with the inner tube and a second port in fluid communication with the outer tube.

8. The ion implantation system according to claim 7, characterized in that: The first port extends through the inner cover and the outer cover of the first tube adapter, and the second port extends through the outer cover of the first tube adapter.

9. The ion implantation system according to claim 1, characterized in that: Each of the first tube adapter and the second tube adapter includes a conductive material.

10. The ion implantation system according to claim 1, characterized in that: The second tube adapter also includes a third port in fluid communication with the inner tube.

11. The ion implantation system according to claim 10, characterized in that: The third port extends through the inner cover and the outer cover of the second tube adapter.

12. An ion implantation system, characterized in that: Include: An ion implanter, inside a housing, includes an ion source unit; a dopant source gas storage tank located in a gas box container outside the housing; a dopant source gas supply pipe, for supplying a dopant source gas from the dopant source gas storage tank to the ion source unit, the dopant source gas supply pipe comprising: an inner tube for conveying the dopant source gas; an outer tube surrounding the inner tube and used to transport an inert gas; a first tube adapter connected to a first end of each of the inner tube and the outer tube, the first tube adapter connecting the inner tube to the dopant source gas storage tank, the first tube adapter comprising a first inner cover and a first outer cover, the first outer cover being separated from the first inner cover by a first gap, a size of the first inner cover being larger than a size of the first end of the inner tube so as to enclose the first end of the inner tube within the first inner cover, and a size of the first outer cover being larger than a size of the first end of the outer tube so as to enclose the first end of the outer tube within the first outer cover; and a second tube adapter connected to a second end of each of the inner tube and the outer tube, wherein the second end is opposite to the first end, the second tube adapter connecting the inner tube to the ion source unit, the second tube adapter comprising a second inner cover and a second outer cover, the second outer cover being separated from the second inner cover by a second gap, a size of the second inner cover being larger than a size of the second end of the inner tube so as to enclose the second end of the inner tube in the second inner cover, and a size of the second outer cover being larger than a size of the second end of the outer tube so as to enclose the second end of the outer tube in the second outer cover; and A pressure sensor is used to measure a pressure level of the inert gas in the outer tube.

13. The ion implantation system according to claim 12, characterized in that: Each of the inner tube and the outer tube includes an electrically insulating material.

14. The ion implantation system according to claim 12, characterized in that: The first tube adapter comprises: an inner cover sealing the first end of the inner tube; an outer cover sealing the first end of the outer tube; a first inlet port extending through the inner cover and the outer cover to fluidly communicate with the inner tube; and A second inlet port extends through the outer cover to be in fluid communication with the outer tube.

15. The ion implantation system according to claim 12, characterized in that: The second tube adapter comprises: an inner cover sealing the second end of the inner tube; an outer cover sealing the second end of the outer tube; and An outlet port extends through the inner cover and the outer cover to be in fluid communication with the inner tube.

16. The ion implantation system according to claim 12, characterized in that: Each of the first tube adapter and the second tube adapter comprises stainless steel.

17. The ion implantation system according to claim 12, characterized in that: Each of the inner tube and the outer tube includes a plurality of grooves on an outer surface thereof.

18. The ion implantation system according to claim 12, characterized in that: The gas box container is at a ground potential.

19. A method for transporting a dopant source gas to the ion implantation system of claim 1, characterized in that: Include: Fill with an inert gas having a predetermined pressure The outer tube of the dopant source gas supply tube as claimed in claim 1; Supplying the dopant source gas from the dopant source gas storage tank to an ion source unit of the ion implanter via the inner tube of the dopant source gas supply tube surrounded by the outer tube; monitoring a pressure of the inert gas in situ; and If the pressure of the inert gas is lower than a predetermined threshold, a leak of the dopant source gas supply pipe is determined.

20. The method according to claim 19, characterized in that The method further includes stopping the supply of the dopant source gas by closing a stop valve connected to the dopant source gas storage tank.

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