A DRY NOM-PLASIVIA TREATMENT SYSTEM AND METHOD OF USING

CROSS-REFERENCE TQ RELATED APPLiCATiONS

[0001] This application is based on and derives the benefit of the filing date of United States Paiem Application No 11/425,883, filed June 22, 2006 This application is relateα to pending United States patent application serial no 10/705 200, entitled ' ^D rocesssng System and Method for Chernicaily Treating a Substrate", Attorney Qocket no 071469/0306773, filed on November 12, 2003, pending United States patent application serial no 10/704,969 entitled "Processing System and Method for Thermaϋy Treating a Substrate", Attorney docket no 071469/0306775, tiled on Novembsr 12 2003, pending United States patent application serial no 10/705,201 , entitled "Processing System and Method for Treating a Substrate" Attorney docket ro 071469/0306772, filed on November 12, 2003, pending United States patent application serial no 11/390 470, entitled "Batch Processing System and Method for Performing Chemical Oxide Removal", Attorney docket no 313530-P0025, filed on March 28, 2006, pending United States patent application serial no 10/859 975, entitled ' Method of Operating a Processing System for Treating a Substrate", Attorney docket no 071489-0309935 filed on June 4, 2004, and pending United States patent application serial no 10/860,149, entitled "Processing System and Method for Treating a Substrate ', Attorney docket no 071469-0309092, filed on June 4 2004 The entire contents of all of these applications are herein incorporates Oy reference n their entirety.

BACKGROUND OF THE INVENTION

Field of the invention

[0002] The present invention relates to a dry non-plasma treatment system ana method for treating a substrate to remove oxide and more particularly to a dry non- plasma t ^r eatment system and method for chemical and thermal treatment of a substrate

Descπpi on of Related Art

In mateπal processing methodoiogies, pattern etching comprises the application of a thin layer of light-sensitive material, such as photoresist to an upper surface of a substrate, that is subsequently patterned in order to provide a mask for ransfemng this pattern to the underlying thin film during etching The patterning of the isght-sensitive materia! generally involves exposure by a radiation source through a reticle (ana associated optics) of the hght-sensitive materia! using, for example, a mscro-hthography system followed by the removal of the irradiated regions of the hght-seηsiϊive materia! (as in the case of positive photoresist), or non-irradiated regions <as \r tne case of negative resist) using a developing solvent [0004] Additionally muSti-iayer and hard masks can be implemented for etching features m a :hsπ film For example, when etching features sn a thin film using a hard mask, the mask pattern in the light-sensitive layer is transferred to the hard mask layer using a separate etch step preceding the mam etch step for the thin film The hard mask can for example be selected from several materials for silicon processing including silicon dioxide (SiO ₂ ), silicon nitride (SIaN ₄ ), and carbon, for example

[0005] In order to reduce the feature size formed in the thin fiim, the hard mask can be tπm?rβα laterally using, for example, a two-step process involving a chemical treatment of the exposed surfaces of the hard mask layer m order to alter the surface chemistry of the hard mask layer, and a post treatment of the exposed surfaces of the hard masK layer order to desorb the altered surface chemistry

Summary of the Invention

[0006] The present invention relates to a dry non-plasma treatment system and method for treating a substrate, and to a dry non-plasma treatment system and method tor cnemically and inermaily treating a substrate

[0007] Any of these and/or other aspects may be provided by a treatment system for removing oxide materia! in accordance with tne present invention in one embodiment, the treatment system for removing oxsde mateπal on a substrate comprises a temperature controlled process chamber configured to contain the substrate having tne oxide materia! thereon A temperature controlled substrate holder ss mounted within the process chamber, and configured to be substantially

thermally Isolated from the process chamber and configured to support the substrate. A vacuum pumping system is coupled to the process chamber. A chemical treatment system is coupled to the process chamber and configured to introduce a process gas comprising as incipient ingredients HF and optionally ammonia (NiHs) to the process chamber, wherein the process gas chemically alters exposed surface layers on the substrate. A thermal treatment system is coupled to the process chamber and configured to elevate the temperature of the substrate, wherein the elevated temperature causes evaporation of the chemically altered surface layers. A controller configured to control the amount of the process gas introduced to the substrate, and the temperature to which the substrate is set. [0008] In another embodiment, a method and computer readable medium for removing oxide material on a substrate comprises disposing the substrate having the oxide material on a substrate holder in a process chamber. The substrate is chemically treated by exposing the substrate to a gas composition comprising as incipient ingredients HF and optionally ammonia (NH ₃ ), while using the substrate holder to set the temperature of the substrate to a chemical treatment temperature less than 100 degrees C. Following the chemical treatment, the substrate is thermally treated by heating the substrate to a temperature above the chemical treatment temperature.

Brief Description of the Drawings

[0009] In the accompanying drawings:

[001 OJ FIG. 1 presents a block diagram of a dry non-plasma treatment system for performing a chemical oxide removal process according to an embodiment of the present invention;

[0011] FIG. 2 presents a dry non-plasma treatment system for performing a dry, non- plasma chemical removal process according to another embodiment of the present invention;

[0012] FIGs. 3A and 3B present a substrate holder for performing a dry, non-piasma chemical removal process according to another embodiment of the present invention;

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[0013| FlGs. 4A and 4B present a substrate holder for performing a dry, non-plasma chemica! removal process according to another embodiment of the present invention; and

[0014| FlG. 5 presents a flow chart of a method of performing a dry, non-plasma chemical removai process according to an embodiment of the present invention.

Detaijed Description of Exemplary Embodiments

[0015] in the following description, for purposes of explanation and not limitation, specific details are set forth, such as a particular geometry of the treatment system and descriptions of various components and processes. However, it should be understood that the invention may be practiced in other embodiments that depart from these specific details.

[001S] According to one embodiment, FIG. 1 presents a treatment system 101 for processing a substrate using a dry, non-plasma, treatment process, such as a chemica! oxide removal process, to, for example, trim an oxide mask or remove native oxide or remove a SiO _x -containing residue. For example, the treatment system 101 is configured to facilitate a chemica! treatment process during which oxide material on the substrate is chemically altered and a thermal treatment process during which chemically altered substrate materia! is desorbed. [0017] FIG. 1 presents a block diagram of a treatment system 101 for treating the oxide material on a substrate. Treatment system 101 includes a process chamber 110 configured to process the substrate, a chemical treatment system 120 coupled to the process chamber 110 and configured to introduce a process gas to the substrate mounted in process chamber 110, a thermal treatment system 130 coupled to process chamber 110 and configured to elevate the temperature of the substrate, and a controller 150 coupled to the process chamber 110. the chemica! treatment system 120 and the thermal treatment system 130, and configured to control the treatment system 101 according to a process recipe. [0018] For example, the chemical treatment system 120 is configured to introduce a process gas comprising a first gaseous component having as an incipient ingredient HF and an optional second gaseous component having as an incipient ingredient ammonia {NH ₃ ). The two gaseous components may be introduced together, or independently of one another. For example, independent gas/Vapor delivery

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systems may be used to introduce each gaseous component. Additionally, the chemical treatment system 120 can further include a temperature control system for elevating the temperature of the vapor delivery system in order to prevent the condensation of process vapor therein.

[0019] Additionally, either gaseous component, or both, can be introduced with a carrier gas, such as an inert gas. The inert gas can comprise a noble gas, such as argon. Of course, other gasses can also be included in the process gas. The chemical treatment of the oxide material on the substrate by exposing this material to the two gaseous components causes a chemical alteration of the oxide material surface to a self-limiting depth. During the chemical treatment of the oxide material on the substrate, the substrate temperature can be controlled. For example, the substrate temperature can be set to a chemical treatment temperature less than 100 degrees C.

[0020] Referring still to FIG. 1 , the thermal treatment system 130 can elevate the temperature of the substrate to a temperature above the chemical treatment temperature, or a temperature range from approximately 50 degrees C to approximately 450 degrees C, and desirably, the substrate temperature can range from approximately 100 degrees C to approximately 300 degrees C. For example, ϊne substrate temperature may range from approximately 100 degrees C to approximately 200 degrees C. The thermal treatment of the chemically altered oxide surface layers causes the evaporation of these surface layers. [0021] Controller 150 Includes a microprocessor, memory, and a digital I/O port (potentially including D/A and/or A/D converters) capable of generating control voltages sufficient to communicate and activate inputs to the process chamber 110, the chemical treatment system 120 and the thermal treatment system as well as monitor outputs from these systems. A program stored in the memory is utilized to interact with the systems 120 and 130 according to a stored process recipe. [0022] Alternately, or in addition, controller 150 can be coupled to a one or more additional controllers/computers (not shown), and controiSer 150 can obtain setup and/or configuration information from an additional controller/computer. [0023] In FIG. 1 , singular processing elements (120 and 130) are shown, but this is not required for the invention. The processing system 101 can comprise any number of processing elements having any number of controllers associated with them in addition to independent processing elements.

[0024] The controller 150 can be used to configure any number of processing elements (120 and 130), and the controller 150 can collect provide, process store, and dssplay data from processing elements The controller 150 can comprise a number of applications for controlling one or more of the processing elements For example, controller 150 can include a graphic user interface (GUI) component (not shown) that can provide easy to use interfaces that enable a user to monitor and/or conirol one or more processing elements

[0025] The processing system 101 can also compπse a pressure control system mot shown) The pressure control system can be coupled to the processing chamber 110, but this is not required In alternate embodiments, the pressure control system can be configured differently and coupled differently The pressure control system can include one or more pressure valves (not shown) for exhausting the processing chamber 1 10 and/or for regulating the pressure within the processing chamber 110 Alternately the pressure control system can also include one or more pumps \ not shown) For example, one pump may be used to increase tne pressure within the processing chamber, and another pump may be used to evacuate the processing chamber 110 In another embodiment, the pressure control system can compπse seals for sealing the processing chamber

[0026J Furthermore, the treatment system 101 can compπse an exhaust control system The exhaust control system can be coupled to the processing chamber 110, but this is not required In alternate embodiments, the exhaust control system can Pe configured differently and coupled differently The exhaust control system can include an exhaust gas collection vessel (not shown) and can be used to remove contaminants from the processing fluid Alternately, the exhaust control system can Pe used to recycle the processing fluid

[0027] Refernng now to FiG 2 a simplified block diagram of a treatment system 200 is snown according to another embodiment The treatment system 200 comprises a treatment chamber 210, a temperature controlled substrate holder 220 configured to be substantially thermally isolated from the treatment chamber 210 and configured to support a substrate 225, a vacuum pumping system 250 coupled to the treatment chamber 210 to evacuate the treatment chamber 210, a chemical distribution system 240 coupled to treatment chamber 210 and configured to introduce a process gas into a process space 245 in order to chemically treat substrate 225, and a radiative heating system 230 coupled to treatment chamber

210 and configured to thermaiiy treat substrate 225 Substrate 225 can be ransferreα info and out of treatment chamber 210 through via a substrate transfer system _v iot shown) through a transfer opening (not shown) [0028] Tne cnemscai distribution system 240 is configured to introduce a process gas cor( ^s gured to for example, chemically after oxide materia! on substrate 225 The chen.ca distribution system 240 is configured to introduce one or more process gases snc.udsng, out not limited to, HF, NH ₃ , N ₂ , H ₂ O ₂ CO, GCX NO NO ₂ , N ₂ O, C _x Py (wrere x y are integers) C _X H _Z F _V (where x, y, z are integers), etc For example :ie orocess cas can comprise a first gaseous component having as an incipient ngredient ^F and an optional second gaseous component having as ar incipient 'ngredιe ⁿ t ammonia (MH ₃ ) The two gaseous components may be introduced togetner or nαependentiy of one another using a gas supply system 242 For example independent gas/vapor supply systems may be used to introduce each gaseous corDonent Additionally, the chemical distribution system 240 can furthe ^r include a terroerature control system for elevating the temperature of the chemical αsstπoutson system 240 <n order to prevent the condensation of process vapor jnerem Additionally either gaseous component or both can be introduced with a ea ^r ner gas, Sv.cn as an men gas The inert gas can comprise a noble gas such as argof O ^f course other gaseous can also be included [GG29J As illustrated in FIG 2 the chemical distribution system 240 can be arranged beyond a oeπpheral edge of substrate 225 The cheiiscal distribution system 240 may comprise a plurality of injection oπffces, or nozzles distributed about tne ci ^r cumference of process space 245 Additionally alternating groups of one O^ rro-e o ^r ήces or nozzies may be used io independently introduce each caseo,.s component e g HF and ammonia Alternatively, the cnemical distribution system 24C can be arrangeα within the radiative heating system 230 Alternatively, tie cnemscai distribution system 240 can be arranged within an upper assembly above substrate 225, while radiative heating system 230 is located beyc ^* >d a oeπp^erai edge of the chemical distribution system 240 yet withn view o ^f substrate 225 Chem'cas d ⁱ stribution system 240 can be a multi-zone flu d distribution system to adjust t^e low of process gas to multiple zones within treatment chamber 210 [0030] Aαdπonaiiy the radiative heating system 230 is configured to heat suostrate 225 in ofder to for example, desorb chemically altered oxide material on substrate 225 ^{"^} he raαiatsve heating system 230 can comprise one or more heat amps Each

heat lamp may, for example, include a tungsten-halogen iamp. Heat lamps, arranged in groups of one or more lamps, may be utilized to spatially adjust the heating of substrate 225. The radiative heating system 230 further comprises a window that Is configured to preserve the vacuum conditions in process chamber 210 and that is substantially transparent to infrared (IR) electromagnetic (EM) radiation. For example, the window may comprise quartz or desirably sapphire. Although, the window (when fabricated of quartz) may be consumed in the dry non- plasma process, the thickness may be selected to be sufficiently thick to reduce the frequency of its replacement and the associated replacement costs. [0031] Referring still to FiG. 2, the substrate holder 220 comprises a substrate temperature control system 280 configured to perform at least one of monitoring, adjusting or controlling or a combination of two or more thereof, the temperature of substrate holder 220 or substrate 225 or both. For example, the substrate holder 220 and substrate temperature control system 260 may comprise a substrate clamping system (i.e., electrical or mechanical clamping system) to improve thermal contact between substrate 225 and substrate hoider 220, a heating system, a cooling system, a substrate backside gas supply system for improved thermal conductance between the substrate 225 and the substrate holder 220, a temperature sensor, etc.

[0032] Additionally, the substrate holder 220 comprises a substrate Sift system 262 including a lift pin assembly (not shown) capable of raising and lowering three or more lift pins in order to vertically transfer substrate 225 to and from an upper surface of the substrate hoider 220 and a transfer plane in the process chamber 210, and to vertically transfer substrate 225 to and from an upper surface of the substrate hoider 220 and a heating plane in the process chamber 210. Furthermore, the substrate holder 220 can comprise a backside gas supply system 264 configured to supply gas to the backside of substrate 225.

[0033] During chemical treatment of substrate 225, substrate 225 rests on substrate holder 220 and the temperature is controlled to a chemical treatment temperature less than approximately 100 degrees C while the substrate 225 is exposed to process gas configured to chemically alter oxide material on substrate 225. During chemical treatment, substrate 225 may be clamped to the substrate holder 220 and a flow of backside gas can be initiated from a backside gas suppiy

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system 284 Io affect improved thermal conductance between the substrate 225 and the substrate holder 220.

|0034] Following the chemical treatment of substrate 225, the temperature of substrate 225 is elevated using radiative heating system 230 in order to desorb the chemically altered oxide materiai. During the thermal treatment of substrate 225, the substrate 225 can be raised above substrate holder 220 and displaced from the substrate holder 220 to the heating plane using substrate lift system 262 by a distance sufficient to substantially thermally decouple the substrate 225 from substrate holder 220. Furthermore, the substrate 225 may be lifted to close proximity with the radiative heating system 230 in order to reduce the extent to which other chamber components see the radiative heating system 230 during heating. Preferably, substrate 225 is heated while other chamber components are not. Additionally, when substrate 225 is raised above substrate holder 220, an optional flow of purge gas from backside gas supply system 264 can be conducted in order to reduce contamination of the backside of substrate 225 during the desorption process.

[0035] Referring now to FIGs. 3A, 3B ₁ 4A and 4B, a substrate holder assembly 300 Is depicted according to another embodiment. The substrate holder assembly 300 comprises substrate holder 320 configured to support substrate 325 and configured to be coupled to process chamber 310. The substrate holder assembly 300 further comprises an electrostatic clamping (ESC) system 380 having a clamp electrode 382 configured to electrically clamp substrate 225 to substrate holder 220. [0036] Additionally, the substrate holder assembly 300 comprises a substrate temperature control system 360. The substrate temperature control system 380 includes a heat exchanger configured to circulate a heat transfer fluid through a fluid channel 366 disposed in substrate hoider 320 by supplying the heat transfer fluid through an inlet fluid supply Sine 362 and receiving the heat transfer fluid through an outlet fluid supply line 364. By adjusting the fluid temperature in the heat exchanger, the temperature of substrate holder 320 can be adjusted. Although only a single zone fluid circulation system is shown, the circulation system may comprise multiple fluid zones.

[0037] Furthermore, the substrate holder assembly 300 comprises a substrate lift system 370 including a lift pin assembly capable of raising and lowering three or

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more lift pins in order to vertically transfer substrate 325 to and from an upper surface of the substrate holder 320 and a transfer plane in the process chamber 310. |0038] In the lift pin assembly, substrate lift pins 372 can be coupled to a common lift pin element, and can be lowered to below the upper surface of substrate holder 320. A drive mechanism utilizing, for example, an electric drive system (having an electric stepper motor and threaded rod) or a pneumatic drive system (having an air cylinder), provides means for raising and lowering the common lift pin element Substrate 325 can be transferred into and out of process chamber 310 through a gate valve (not shown) and chamber feed-through passage, aiigned on the transfer plane, via a robotic transfer system (not shown), and received by the substrate lift pins. Once the substrate 325 is received from the transfer system, it can be lowered to the upper surface of the pedestal 320 by lowering the substrate lift pins 372 (see FIGs. 3A and 4A). Moreover, the substrate 325 may be raised above substrate holder 320 during the heating of substrate 325 (see FiGs. 3B and 4B). The substrata lift pins 372 may comprise pin caps 374 fabricated from a thermally insulating material such as quartz or sapphire, in order to thermally decouple the substrate 325 from the substrate lift pins 372.

[0039] Further yet, substrate holder assembly 320 comprises a backside gas supply system 364 configured to supply a heat transfer gas _; or a purge gas _: or both to the backside of substrate 325. During chemical treatment of substrate 325, the substrate 325 can be clamped to substrate holder 320 using ESC system 380 while the backside gas supply system 364 supplies heat transfer gas, such as helium, to ihe backside of substrate 325 in order to improve the thermal contact between substrate 325 and substrate holder 320 (see FIGs. 3A and 4A). The substrate temperature control system can then be utilized to adjust the temperature of substrate 325. During the thermal treatment of substrate 325, the substrate 325 can be raised above the substrate holder using the substrate lift system 370 while the backside gas supply system 364 supplies a purge gas flow 390 io the backside of substrate 325 in order to reduce contamination of the substrate backside (see FIGs, 3B and 4B).

[0040] During chemical treatment of substrate 325, substrate 325 rests on substrate holder 320 and the temperature is controlled to a chemical treatment temperature less than approximately 100 degrees C while the substrate 325 is exposed to process gas configured to chemically alter oxide material on substrate

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325. During chemical treatment, substrate 325 may be damped to the substrate holder 320 using ESC system 380 and a flow of backside gas can be initiated from backside gas supply system 364 in order to affect improved thermal conductance between the substrate 325 and the substrate holder 320 (see FIGs. 3A and 4A). [0041] following the chemical treatment of substrate 325, the temperature of substrate 325 is elevated using a radiative heating system 330 above substrate 325 in order to desorb the chemically altered oxide material. During the thermal treatment of substrate 325, the substrate 325 can be raised above subsirate holder 320 and displaced from the substrate holder 320 using substrate lift system 362 by a distance sufficient to substantially thermally decouple the substrate 325 from substrate holder 320. Furthermore, the substrate 325 may be lifted to close proximity with the radiative heating system 330 in order to reduce the extent to which other chamber components see the radiative heating system 330 during heating. Preferably, substrate 325 is heated while other chamber components are not. Additionally, when substrate 325 is raised above substrate holder 320, an optional flow of purge gas from backside gas supply system 364 can be conducted in order to reduce contamination of the backside of substrate 325 during the desorption process (see FiGs. 3B and 4B).

[0042] Furthermore, referring to FIGs. 4A and 4B, a radiation shield 332 may be utilized to reduce the heating of other chamber components during the heating of substrate 325. Substrate 325 can, for example, be lifted to close proximitiy with the bottom of radiation shield 332. The radiation shield 332 may comprise one or more openings 334 In order to permit the passage of gaseous material originating from substrate 325 during heating. Additionally, a purge gas, such as an inert gas (e.g., a noble gas, N?, etc.), can be introduced to the space enclosed by radiation shield 332, substrate 325 and radiative heating system 330 during thermal treatment of substrate 325. Furthermore, the radiation shield may be coupled to the upper portion of process chamber 310. The radiation shield may be a bare metal shield or a ceramic shield, or it may be an anodized metal shield or coated metal shield, for example.

[0043] Referring again to FlG. 2, vacuum pumping system 250 can comprise a vacuum pump and a gate valve for adjusting the chamber pressure. Vacuum pumping system 250 can, for example, include a turbo-moiecuiar vacuum pump (TMP) capable of a pumping speed up to about 5000 liters per second (and greater).

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For example, the IMP can be a Seiko STP-A803 vacuum pump, or an Ebara ETI 301VV vacuum pump. TMPs are usefu! for low pressure processing, typically less than about 50 mTorr. For high pressure (i.e., greater than about 100 mTorr) or low throughput processing (i.e., no gas flow), a mechanical booster pump and dry roughing pump can be used.

[0044] Referring still to FlG. 2. treatment system 200 can further comprise a controller 270 having a microprocessor, memory, and a digital I/O port capable of generating control voltages sufficient to communicate and activate inputs to treatment system 200 as well as monitor outputs from treatment system 200 such as temperature and pressure sensing devices. Moreover, controller 270 can be coupled to and can exchange information with substrate holder 220, chemical distribution system 240, gas supply system 242, radiative heating system 230, vacuum pumping system 250, substrate temperature control system 260, substrate sift system 282. and backside gas supply system 264. For example, a program stored in the memory can be utilized to activate the inputs to the aforementioned components of treatment system 200 according to a process recipe. One example of controller 270 Is a DELL PRECISION WORKSTATION 610™ , available from Deli Corporation, .Austin, Texas.

[0045] The controller 270 may also be implemented as a general purpose computer, processor, digital signal processor, etc., which causes a substrate processing apparatus to perform a portion or ail of the processing steps of the invention in response to the controller 290 executing one or more sequences of one or more instructions contained in a computer readable medium. The computer readable medium or memory for holding instructions programmed according to the teachings of the invention and for containing data structures, tables, records, or other data described herein. Examples of computer readable media are compact discs, hard disks, floppy disks, tape, magneto-optical disks, PROMs (EPROM, EEPROM. flash EPROM), DRAM, SRAM, SDRAM, or any other magnetic medium, compact discs (e.g., CD-ROM), or any other optical medium, punch cards, paper tape, or other physical medium with patterns of holes, a carrier wave, or any other medium from which a computer can read.

[0046] The controller 270 may be locally located relative to the treatment system 200. or it may be remotely located relative to the treatment system 200 via an internet or intranet. Thus, the controller 270 can exchange data with the treatment

system 200 using at least one of a direct connection, an intranet, and the internet. The controller 270 may be coupled to an intranet at a customer site (i.e., a device maker, etc.), or coupled to an intranet at a vendor site (i.e., an equipment manufacturer). Furthermore, another computer (i.e., controller, server, etc.) can access controller 270 to exchange data via at least one of a direct connection, an intranet, and the internet.

[0047] Referring now to FfG. 5, a method of performing a dry non-plasma treatment of a substrate is presented according to an embodiment. The treatment process can, for example, include a process for removing oxide material on the substrate. The dry, non-piasma treatment process includes a chemical process during which exposed surfaces of a substrate having an oxide material are chemically treated by a process gas comprising HF. or ammonia (NHs), or both HF and NH ₃ as incipient ingredients. Exposure to incipient HF and/or NH ₃ can remove oxide material, such as oxidized silicon (or SiO _x ), and/or consume oxide materia! by displacing such material with a chemically treated material. The self limiting feature results from a reduced rate of removal and/or chemical altering of the oxide material as exposure to the process material proceeds.

[0048] Following the chemical treatment process, a desorption process is performed in order to remove the chemically altered surface layers. Due to the self- limiting feature of the chemical treatment process, it may be desirable to aiternatingiy perform the non-piasma etch and subsequent desorption process, which can ailow precise control of the removal process. The desorption process can comprise a thermal treatment process within which the temperature of the substrate is raised sufficiently high to permit the volatilization of the chemically altered surface layers. [0049] The method includes a flow chart 500 beginning in step 510 with disposing the substrate in a treatment system configured to facilitate the chemical and desorption processes. For example, the treatment system comprises one of the systems described in FIGs. 1 or 2.

[OOSø] In step 520, oxide material on the substrate is chemically treated. During the chemical treatment process of the dry non-plasma treatment, each constituent of the process gas may be introduced together (i.e., mixed), or separately from one another (i.e., HF introduced independently from NH ₃ ). Additionally, the process gas can further include an inert gas, such as a noble gas (i.e., argon). The inert gas may be introduced with either the HF or the NH ₃ , or it may be introduced independently

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from each of the aforementioned gaseous constituents. Further details regarding the introduction of a noble gas with NH ₃ in order to control the removal of silicon dioxide is described In pending US Patent Application Serial No. 10/812,347, entitled "Processing System and Method For Treating a Substrate", the entire contents of which are herein incorporated by reference in their entirety. [0051] Additionally, during the chemical treatment process, the process pressure may be selected to affect the amount of oxide material removed. The process pressure can range from approximately 1 mtorr to approximately 100 torr. Furthermore, during the chemical treatment process, the substrate temperature may be selected to affect the amount of oxide materia! removed. The substrate temperature can range from approximately 10 degrees C to approximately 200 degrees C, or the substrate temperature can be iess than 100 degrees C. For example, the temperature can range from approximately 10 degrees C to 50 degrees C, Further details regarding the setting of the substrate temperature in order to control the removal amount is described in pending US Patent Application Serial No. 10/817,417, entitled "Method and System For Performing a Chemical Oxide Removal Process", the entire contents of which are herein incorporated by reference in their entirely.

[0052] In step 530, chemically altered oxide material on the substrate is thermally treated. During the thermal treatment process, the substrate temperature can be elevated above approximately 50 degrees C, or above approximately 100 degrees C. Additionally, an inert gas may be introduced during the thermal treatment of the substrate. The inert gas may include a noble gas or nitrogen. [0053] Additionally, during the chemical and thermal treatments of the substrate, the process chamber can be configured for a temperature ranging from about 10° to about 450 ⁰ C. Alternatively, the chamber temperature can range from about 30° to about 60° C. The temperature for the substrate can range from approximately 10° to about 450° C. Alternatively, the substrate temperature can range form about 30° to about 60° C.

[00S4] In one example, part of or ail of an oxide film, such as a native oxide film, is removed on the substrate using a chemical oxide removal process, in another example, pan of or all of an oxide film, such as an oxide hard mask, is trimmed on a substrate using a chemical oxide removal process. The oxide film can comprise

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silicon dsoxsde (S1O ₂ ) or more generally, SiO _x , for example In yet another example part or a»! of a SiO _x -contaιnιng residue is removed on the substrate [0055] Although only certain emoodiments of this invention have been descπbed in detail above those skilled in the art will readily appreciate that many rnoaificatsons a^e possible p the embodiments without materially departing from the novel teacπiπgs and advantages of this invention Accordingly ali such modifications are sπtendeα 10 be πclυded within the scope of this invention