Efficient cleaning and etching of high aspect ratio structures

Abstract

A method for processing a substrate includes: placing a substrate in a processing chamber. Supplying at least one of a vaporized solvent and a gas mixture containing the solvent to the processing chamber to form a conformal liquid layer of the solvent on an exposed surface of the substrate. Removing the vaporized solvent and the at least one of the gas mixture from the processing chamber. Supplying a reactive gas containing a halogen substance to the processing chamber. The conformal liquid layer adsorbs the reactive gas to form a reactive liquid layer, and the reactive liquid layer etches the exposed surface of the substrate.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 684,415, filed on June 13, 2018. The entire disclosure of the above-referenced application is incorporated herein by reference. Technical Field

[0003] The present invention relates to substrate processing methods, and more particularly, to methods for efficiently cleaning and etching substrates containing high aspect ratio (HAR) structures. Background Art

[0004] The background description provided here is for the purpose of generally presenting the context of the present disclosure. The work of the presently designated inventors is neither explicitly nor implicitly admitted to be prior art against the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed.

[0005] The manufacture of substrates such as semiconductor wafers typically requires multiple processing steps, which may include material deposition, planarization, feature patterning, feature etching, and / or feature cleaning. These processing steps are typically repeated one or more times during substrate processing. As semiconductor devices continue to shrink to smaller feature sizes, high aspect ratio (HAR) structures such as vias and trenches are increasingly needed to achieve desired device performance goals. HAR structures present challenges to wet cleaning and wet etching efficiency due to reduced diffusion and surface charge layer overlap in geometrically confined spaces. Summary of the invention

[0006] A method for processing a substrate comprises: a) placing a substrate in a processing chamber; b) supplying at least one of a vaporized solvent and a gas mixture to the processing chamber to form a conformal liquid layer of the solvent on an exposed surface of the substrate; c) removing the vaporized solvent and the at least one of the gas mixture from the processing chamber; and d) supplying a reactive gas containing a halogen substance to the processing chamber. The conformal liquid layer adsorbs the reactive gas to form a reactive liquid layer, and the reactive liquid layer etches the exposed surface of the substrate.

[0007] In other features, the reactive liquid layer reacts with the exposed surface of the substrate to produce a gas product. The exposed surface of the substrate is etched without forming a residue. The at least one of the vaporized solvent and the gas mixture is selected from the group consisting of a polar solvent, water, peroxide, isopropyl alcohol, acetone, carbon tetrachloride, hexane, methanol, and ethanol.

[0008] In other features, the reactive gas is selected from the group consisting of hydrogen fluoride gas, hydrogen chloride gas, and hydrogen bromide gas. The substrate includes a plurality of high aspect ratio (HAR) features having a depth to width ratio of greater than or equal to 5:1.

[0009] In other features, before supplying the at least one of the vaporized solvent and the gas mixture to the process chamber, the pressure in the process chamber is set to a pressure range of from 1 Torr to 10 Torr. Before supplying the at least one of the vaporized solvent and the gas mixture to the process chamber, the process temperature in the process chamber is set to a temperature range of from 0° C. to 400° C. Before supplying the at least one of the vaporized solvent and the gas mixture to the process chamber, the process temperature in the process chamber is set to a temperature range of from 150° C. to 400° C.

[0010] In other features, the reactive liquid layer etches the exposed surface at an etch rate in a range of 10 angstroms / min to 100 angstroms / min. In other features, the method includes performing a plurality of cycles including a) to d).

[0011] In other features, the reactive liquid layer etches the exposed surface by 0.2 angstroms to 1 angstrom during each cycle of the plurality of cycles. In other features, the method further comprises, prior to b): supplying an oxidizing gas to the process chamber for a predetermined period of time; and exhausting the oxidizing gas.

[0012] In other features, the oxidizing gas comprises a gas selected from the group consisting of molecular oxygen, ozone, hydrogen peroxide, nitrous oxide, and nitrogen dioxide. The oxidizing gas is supplied via a remote plasma. The oxidizing gas is supplied at a process temperature in a range of 100° C. to 400° C.

[0013] In other features, the method includes: performing a wet clean of the substrate after d). The reactive liquid layer reacts with the exposed surface of the substrate to produce a gas product. The exposed surface of the substrate is etched without forming a residue. In other features, a) to d) are performed in an inductively coupled plasma (ICP) chamber.

[0014] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0016] Figure 1 is a side cross-sectional view of an example of a substrate including a high aspect ratio (HAR) structure;

[0017] Figure 2A and 2B is a side cross-sectional view of an example of a substrate during substrate cleaning or etching according to the present disclosure;

[0018] Figure 3 A flowchart of an example of a method for cleaning or etching a substrate according to the present disclosure;

[0019] Figures 4A to 4C is a side cross-sectional view of a substrate during substrate cleaning or etching according to the present disclosure;

[0020] Figure 5 A flowchart of an example of a method for cleaning or etching a substrate according to the present disclosure;

[0021] Fig. 6A and 6B is a functional block diagram of a processing chamber according to the present disclosure; and

[0022] Figure 7 is a functional block diagram of a substrate processing tool including at least a processing chamber for cleaning and etching according to the present disclosure.

[0023] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. Specific implementation plan

[0024] As features shrink in advanced process nodes, high aspect ratio (HAR) structures become more common. As used herein, HAR structures refer to features with aspect ratios greater than 5:1, 10:1, or 20:1. HAR structures present challenges to wet cleaning and wet etching efficiency due to reduced diffusion and overlapping surface charge layers in geometrically confined spaces. The method according to the present disclosure overcomes this challenge by utilizing a gas or gas phase pretreatment to produce an adsorbed liquid layer that conformally coats the HAR structure and improves subsequent cleaning and removal efficiency.

[0025] Materials diffuse much faster in the gas or vapor phase than in the liquid phase (about ×10 4 ). The methods described herein form a liquid layer of adsorbed reactive species from a gas or gas phase on the HAR structure. Due to the adsorbed liquid layer, the chemical reaction can modify the underlying residue or film on the substrate surface and improve the cleaning efficiency of the residue or the etching efficiency of the film.

[0026] In some examples, the process is performed in a vacuum chamber under vacuum with controlled vapor exposure at a predetermined temperature. In some examples, the pressure is in the range of 1T to 10T. In some examples, the substrate temperature is maintained in the range of 0°C to 400°C during etching or cleaning. In some examples, the substrate temperature is maintained in the range of 150°C to 400°C during etching or cleaning. In other examples, the process is performed in a process chamber at atmospheric pressure. Whether to use a vacuum chamber may be determined by the volatility of the solvent at different process temperatures and / or pressures used during the cleaning or etching steps. If the solvent is not volatile at atmospheric pressure, a vacuum chamber may be used.

[0027] The method according to the present disclosure is similar to atomic layer etching (ALE) in that the reactants are introduced as a gas or gas phase. However, in ALE, the adsorbed layer is mainly a monolayer, and etching stops at a monolayer reaction. Therefore, the etching rate is slow, for example, about 0.2A (angstroms) to 1A of material per cycle. In addition, the ALE process does not solve the problem of cleaning efficiency. The method according to the present disclosure provides a higher etching rate. In some examples, the etching rate is about 10A / min to 100A / min. Compared with wet cleaning chemistry methods, another advantage of the method according to the present disclosure is the inherent high selectivity. The condensed liquid layer acts as effectively as the liquid in the wet cleaning chemistry method.

[0028] Reference now Figure 1 , a substrate 100 includes a first layer 110 and a second layer 114 deposited on the first layer 110. The substrate 100 includes a plurality of high aspect ratio (HAR) structures 108, which are defined in the first layer 110 and the second layer 114. For example, after a previous processing step, particles or residues 120 may be located at the bottom of the HAR structures 108 and may need to be removed. Due to the depth of the HAR structures, the particles or residues 120 may be difficult to remove during cleaning.

[0029] Reference Figure 2A and 2B During the cleaning and / or etching process, the substrate 100 is exposed to a gas mixture or vaporized solvent A(g), where A is the solvent. For example, the substrate 100 can be controlled at a different temperature relative to other components in the process chamber (e.g., the substrate 100 is maintained at a lower temperature). The solvent 100 can be introduced into the process chamber as a gas mixture that condenses into a liquid on the substrate 100. Alternatively, a gas vapor can be supplied to the process chamber.

[0030] exist Figure 2AIn the embodiment of the present invention, the gas or vapor condenses on the second layer 114 and forms a conformal liquid layer 210 (which is adsorbed on the exposed surface of the second layer 114, as shown). In some examples, the solvent is selected from the group consisting of: polar solvents, water (H2O), peroxide (H2O2), isopropyl alcohol (C3H8O or IPA), acetone ((CH3)2CO), carbon tetrachloride (CCl4), hexane (C6H 14 ), methanol (CH3OH or MeOH), ethanol (C2H6O or EtOH) and / or other suitable solvents. In some examples, the solvent used is selected based on the film material of the second layer 114 to be cleaned or etched.

[0031] Subsequently, the substrate 100 is exposed to a reactive gas B(g), wherein B contains a halogen species such as fluorine (F), chlorine (Cl), or bromine (Br), such as Figure 2B . In some examples, the reactive gas includes hydrogen fluoride (HF) gas, hydrogen chloride (HCl) gas, or hydrogen bromide (HBr) gas. The reactive species is adsorbed by the liquid layer 210 to produce a reactive liquid layer 220 including the reactive species. During the etching period or the cleaning period, the reactive liquid layer 220 cleans or etches the second layer 114. The reaction byproducts formed are in the gas phase and leave the HAR without forming any residue, as shown by gas C(g).

[0032] In some examples, such as during a cleaning operation, a wet cleaning step can be performed after exposure to the reactive species in reactive liquid layer 220. In some examples, the wet cleaning step utilizes mild chemicals. In some examples, the wet cleaning step includes rinsing the substrate using deionized water (DIW) or ozone-dissolved deionized water (DIO3).

[0033] Reference Figure 3 , a method 300 for cleaning or etching a substrate is shown. At 310, a substrate is placed in a processing chamber. At 314, the substrate temperature and / or the chamber pressure are controlled. At 318, a gas mixture and / or a vaporized solvent is supplied to the processing chamber for a first predetermined period of time. The gas mixture and / or the vaporized solvent is adsorbed as a liquid layer on the exposed surface of the second layer 114. At 322, a reactive gas is supplied to the processing chamber for a second predetermined period of time. In some examples, the reactive gas comprises a halogen substance. The substrate is exposed to the liquid layer comprising the reactive substance for a third predetermined period of time sufficient for cleaning and / or etching. At 326, a wet etching step may be optionally performed after the cleaning or etching step. The process may be repeated one or more times.

[0034] Reference now Figures 4A to 4C , another processing pair can be used Figure 1The substrate 100 is cleaned or etched. Figure 4A In the process, the substrate 100 is exposed to an oxidizing gas mixture, which oxidizes the exposed surface of the second layer 114, as shown at 410. Figure 4B In the embodiment of the present invention, the substrate 100 is optionally exposed to a gas mixture or vaporized solvent A(g) before being exposed to the reactive gas B(g). The gas mixture or vaporized solvent condenses on the second layer 114 to produce a conformal liquid layer 420. In some examples, the solvent is selected from the group consisting of: polar solvents, water (H2O), peroxide (H2O2), isopropyl alcohol (C3H8O or IPA), acetone ((CH3)2CO), carbon tetrachloride (CCl4), hexane (C6H 14 ), methanol (CH3OH or MeOH), and / or ethanol (C2H6O or EtOH)

[0035] Subsequently, the substrate 100 is exposed to a reactive gas B(g), wherein B contains a halogen species such as fluorine (F), chlorine (Cl), or bromine (Br), such as Figure 4C . The reactive species is adsorbed by the liquid layer 420 to produce a liquid layer 430 containing the reactive species. The liquid layer 430 cleans or etches the second layer 114 during the cleaning period or the etching period, respectively. The reaction byproducts formed are in the gas phase and leave the HAR without forming any residue, as shown by gas C(g).

[0036] In some examples, for example during a cleaning operation, a purely wet cleaning step can be performed using mild chemicals (compared to other cleaning steps such as sulfuric acid peroxide mixture (SPM)) after exposure to reactive species (in liquid layer 430). In some examples, the purely wet cleaning step can include rinsing the substrate using deionized water (DIW) or ozone-dissolved deionized water (DIO3).

[0037] Reference now Figure 5, a method 500 for substrate cleaning or etching is shown. At 510, a substrate is disposed in a processing chamber. At 514, the substrate temperature and / or chamber pressure are controlled. At 518, an oxidizing gas is supplied to the processing chamber during a first predetermined period of time. In some examples, the oxidizing gas comprises molecular oxygen (O2), ozone (O3), peroxide (H2O2), nitrous oxide (N2O), chlorine dioxide (NO2), but other oxidizing gases may also be used. The oxidizing gas may be supplied by using a remote plasma of a remote plasma source (RPS) or by using a thermal reaction at an elevated processing chamber temperature. In some examples, the elevated processing chamber temperature is in the range of 100°C to 400°C. In some examples, for O2, O3, and H2O2, the elevated temperature is in the range of 50°C to 250°C. In some examples, for N2O and NO2, the elevated temperature is in the range of 200°C to 400°C.

[0038] At optional step 522, a gas and / or vaporized solvent is supplied to the processing chamber for a second predetermined period of time. The gas and / or vaporized solvent is adsorbed as a liquid layer on the exposed surface of the second layer 114. At 526, a reactive gas is supplied to the processing chamber for a third predetermined period of time. The reactive gas contains a halogen species. The substrate is exposed to the liquid layer containing the reactive species for a fourth predetermined period of time sufficient for cleaning and / or etching. At 530, a wet etching step may optionally be performed. This process may be repeated one or more times as desired.

[0039] In one example, Figure 5 A method is used to selectively etch TiN / TiSiN films. In this example, thermal oxidation (O3 or O2 / N2) or remote inductively coupled plasma (ICP) (O2 or O2 / N2) is used to supply the oxidizing gas. The oxidation step produces a TiO2 layer. The solvent includes an alcohol, such as IPA, MeOH, or EtOH. The reactive gas includes HCl, HF, or HBr. TiO2 is converted to TiCl x 、TiF y , or TiBr z (wherein x, y and z are integers), which is volatile.

[0040] Figure 5 Advantages of the method include higher cleaning efficiency. Gas diffusion is ~10 higher than liquid diffusion. 4 The process is limited by the oxide thickness, thus providing uniformity control. The extra thickness can be removed by cycling the process one or more times.

[0041] Reference Fig. 6A, an example of a substrate processing chamber 600 for performing etching or cleaning under vacuum is shown. Although a specific substrate processing chamber is shown and described, other types of substrate processing systems can be used to implement the method. For example, a substrate processing system operating at atmospheric pressure can be used. The substrate processing chamber 600 includes a lower chamber area 602 and an upper chamber area 604. The lower chamber area 602 is defined by a chamber sidewall surface 608, a chamber bottom surface 610, and a lower surface of a gas distribution device 614.

[0042] The upper chamber region 604 is defined by the upper surface of the gas distribution device 614 and the inner surface of the dome 618. In some examples, the dome 618 rests on the first annular support 621. In some examples, the first annular support 621 includes one or more spaced holes 623 for delivering process gas to the upper chamber region 604. In some examples, the process gas is delivered in an upward direction at an acute angle relative to a plane including the gas distribution device 614 through the one or more spaced holes 623, but other angles / directions may also be used. In some examples, a gas flow channel 634 in the first annular support 621 supplies gas to the one or more spaced holes 623.

[0043] The first annular support 621 can rest on a second annular support 625 that defines one or more spaced apart holes 627 for delivering process gas from the gas flow channel 629 to the lower chamber region 602. In some examples, holes 631 in the gas distribution device 614 are aligned with the holes 627. In other examples, the gas distribution device 614 has a smaller diameter and the holes 631 are not required. In some examples, the process gas is delivered in a downward direction toward the substrate through the one or more spaced apart holes 627 at an acute angle relative to a plane including the gas distribution device 614, although other angles / directions may also be used.

[0044] In other examples, the upper chamber region 604 is cylindrical with a flat top surface, and one or more flat induction coils may be used. In other examples, a single chamber may be used with a spacer located between the showerhead and the substrate support.

[0045] A substrate support 622 is disposed in the lower chamber region 604. In some examples, the substrate support 622 includes an electrostatic chuck (ESC), although other types of substrate supports may also be used. During etching, a substrate 626 is disposed on an upper surface of the substrate support 622. In some examples, the temperature of the substrate 626 may be controlled by a heater plate 617, an optional cooling plate with fluid channels, and one or more sensors (not shown); however, any other suitable substrate support temperature control system may be used.

[0046] In some examples, the gas distribution device 614 includes a showerhead (e.g., a plate 633 having a plurality of spaced-apart holes 635). The plurality of spaced-apart holes 635 extend from an upper surface of the plate 633 to a lower surface of the plate 633. In some examples, the spaced-apart holes 635 have a diameter in a range of 0.1 inches to 0.75 inches. In some examples, the showerhead is made of a conductive material such as aluminum or a non-conductive material such as a ceramic with an embedded electrode made of a conductive material.

[0047] One or more induction coils 640 are arranged around the outer portion of the dome 618. When powered, the one or more induction coils 640 generate an electromagnetic field inside the dome 618. In some examples, an upper coil and a lower coil are used. The gas injector 642 injects one or more gas mixtures from the gas delivery system 650-1.

[0048] In some examples, gas delivery system 650-1 includes one or more gas sources 652, one or more valves 654, one or more mass flow controllers (MFCs) 656, and a mixing manifold 658, although other types of gas delivery systems may be used. Vapor delivery system 659 delivers vapor including a carrier gas and another gas to the process chamber.

[0049] A gas separator (not shown) may be used to vary the flow rate of the gas mixture.An additional gas delivery system 650-2 may be used to provide an etching gas or etching gas mixture to the gas flow channels 629 and / or 634 (in addition to or in lieu of the etching gas from the gas injector 142).

[0050] Suitable gas delivery systems are shown and described in commonly assigned U.S. Patent Application Serial No. 14 / 945,680, filed on December 4, 2015, entitled "Gas Delivery System", which is incorporated herein by reference in its entirety. Suitable single or dual gas injectors and other gas injection locations are shown and described in commonly assigned U.S. Provisional Patent Application No. 62 / 275,837, filed on January 7, 2016, entitled "Substrate Processing System with Multiple Injection Points and Dual Injector", which is incorporated herein by reference in its entirety.

[0051] In some examples, the gas injector 642 includes a central injection location that directs the gas in a downward direction and one or more side injection locations that inject the gas at an angle relative to the downward direction. In some examples, the gas delivery system 650-1 delivers a first portion of the gas mixture to the central injection location of the gas injector 642 at a first flow rate and delivers a second portion of the gas mixture to the side injection locations of the gas injector 642 at a second flow rate. In other examples, different gas mixtures are delivered by the gas injector 642. In some examples, the gas delivery system 650-1 delivers the conditioned gas to the gas flow channels 629 and 634 and / or other locations of the process chamber, as will be described below.

[0052] The plasma generator 670 can be used to generate RF power that is output to one or more induction coils 640. Plasma 690 is generated in the upper chamber region 604. In some examples, the plasma generator 670 includes an RF source 672 and a matching network 674. The matching network 674 matches the impedance of the RF source 672 to the impedance of the one or more induction coils 640. In some examples, the gas distribution device 614 is connected to a reference potential such as ground. A valve 678 and a pump 680 can be used to control the pressure inside the lower chamber region 602 and the upper chamber region 604 and to evacuate the reactants.

[0053] Controller 676 communicates with gas delivery systems 650-1 and 650-2, valves 678, pumps 680, and / or plasma generator 670 to control the flow of process gases, purge gases, RF plasma, and chamber pressure. In some examples, the plasma is maintained within dome 618 by one or more induction coils 640. One or more gas mixtures are introduced from the top of the chamber using gas injectors 642 (and / or holes 623), and the plasma is confined within dome 618 using gas distribution device 614.

[0054] In some examples, RF bias 684 is provided and includes RF source 686 and optional matching network 688. RF bias power can be used to generate plasma between gas distribution device 614 and substrate support, or to generate self bias on substrate 626 to attract ions. Controller 676 can be used to control RF bias power.

[0055] Reference Figure 6B, the vapor delivery system 659 may include a bubbler or an ampoule. The vapor delivery system 659 includes a carrier gas source 692, which is connected to a mass flow controller 694 via a valve V1. The vapor delivery system 659 also includes valves V2, V3, V4, V5, and V6, which are configured to prevent the flow of, or control the flow of, a carrier gas or a mixture of a carrier gas and a solvent. A temperature sensor 697 and a heater 698 are used to control the temperature of the solvent in the ampoule 696. The carrier gas can be supplied by opening valves P1, V2, V4, V5, and V6. The carrier gas and solvent can be supplied by opening valves V1, V2, V3, V5, and V6 and closing valve V4.

[0056] Reference now Figure 7 , shows a substrate processing tool 710 according to the present disclosure. The substrate processing tool 710 includes a robot 712 disposed at a central position. The robot 712 can operate under vacuum or atmospheric pressure. The substrate processing tool 710 includes a plurality of stations 716-1, 716-2, ..., and 716-S (collectively referred to as stations 716) (where S is an integer greater than one) disposed around the robot 712. The stations 716 can be arranged to be offset at equal or irregular angles around the center of the substrate processing tool 710. Examples of stations 716 may include deposition, etching, pre-cleaning, post-cleaning, spin cleaning, etc. Initially, the substrate may be located in a box 734. The robot and load lock, generally indicated at 738, can be used to move the substrate from the box 734 to the substrate processing tool 710. When the processing is completed, the robot and load lock 738 can return the substrate to the box 734 and / or another box 739.

[0057] In some examples, one of the plurality of stations 716 performs deposition or etching. Another of the plurality of stations 716 performs cleaning or etching as described above. Another of the plurality of stations 716 (e.g., a spin cleaning chamber) performs the wet-only cleaning step described above. In some examples, the substrate is moved by robot 712 from a deposition or etching station to a cleaning or etching station and then to a wet-only cleaning station.

[0058] The foregoing description is merely illustrative in nature and is by no means intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because when studying the drawings, the specification and the appended claims, other modifications will become apparent. It should be understood that, without changing the principles of the present disclosure, one or more steps in the method can be performed in different orders (or simultaneously). In addition, although each embodiment is described above as having certain features, any one or more of those features described relative to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not clearly described. In other words, the described embodiments are not mutually exclusive, and the replacement of one or more embodiments with each other remains within the scope of the present disclosure.

[0059] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be interpreted to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C."

[0060] In some implementations, the controller is part of a system, which can be part of the above examples. Such a system can include a semiconductor processing device, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operations before, during, and after the processing of semiconductor wafers or substrates. The electronic device can be referred to as a "controller", which can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any process disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out tools and other transfer tools and / or load locks connected to or connected to a specific system through an interface.

[0061] In general, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuit can include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors, or a microcontroller that executes program instructions (e.g., software). The program instructions can be instructions sent to the controller in the form of various individual settings (or program files) that define operating parameters for performing a specific process on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the manufacture of one or more (kinds of) layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0062] In some implementations, the controller may be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the "cloud" or all or part of a wafer fab host system that may allow remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of a current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) may provide a process recipe to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., the process and control described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control the process on the chamber.

[0063] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0064] As described above, depending on one or more processing steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools used in material transport to transport wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

Claims

1. A method for processing a substrate, comprising: a) placing a substrate in a processing chamber; and b) simultaneously supplying a vaporized solvent and a reactive gas containing a halogen species to the process chamber to form a conformal liquid layer on an exposed surface of the substrate; wherein the conformal liquid layer adsorbs the reactive gas to form a reactive liquid layer, and the reactive liquid layer etches the exposed surface of the substrate to form gaseous byproducts without forming residues; and The reactive liquid layer etches the exposed surface at an etching rate ranging from 10 angstroms / min to 100 angstroms / min. 2 . The method of claim 1 , wherein the reactive liquid layer reacts with the exposed surface of the substrate to produce a gas product.

3. The method according to claim 1, wherein the reactive gas is selected from the group consisting of hydrogen fluoride gas, hydrogen chloride gas, and hydrogen bromide gas.

4. The method of claim 1, wherein the substrate comprises a plurality of high aspect ratio (HAR) features having a depth to width ratio greater than or equal to 5:

1. 5 . The method of claim 1 , further comprising setting a pressure in the process chamber within a pressure range from 1 Torr to 10 Torr before supplying the vaporized solvent and the reactive gas to the process chamber. 6 . The method according to claim 1 , further comprising setting a process temperature in the process chamber within a temperature range from 0° C. to 400° C. before supplying the vaporized solvent and the reactive gas to the process chamber.

7. The method of claim 1, further comprising: executing a plurality of cycles including a) and b).

8. The method of claim 7, wherein the reactive liquid layer etches the exposed surface by 0.2 angstroms to 1 angstrom during each cycle in the plurality of cycles.

9. The method according to claim 1, further comprising: Before b): supplying an oxidizing gas to the process chamber for a predetermined period of time; and The oxidizing gas is evacuated.

10. The method of claim 9, wherein the oxidizing gas comprises a gas selected from the group consisting of molecular oxygen, ozone, hydrogen peroxide, nitrous oxide, and nitrogen dioxide.

11. The method of claim 9, wherein the oxidizing gas is supplied via a remote plasma.

12. The method of claim 9, wherein the oxidizing gas is supplied at a process temperature in a range of 100°C to 400°C.

13. The method of claim 9, further comprising: performing a wet clean of the substrate after b).

14. The method of claim 1, wherein the exposed surface of the substrate is etched without forming a residue.

15. The method of claim 1, wherein a) and b) are performed in an inductively coupled plasma (ICP) chamber.

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