US20020124962A1 - Atmospheric pressure plasma etching reactor - Google Patents
Atmospheric pressure plasma etching reactor Download PDFInfo
- Publication number
- US20020124962A1 US20020124962A1 US09/804,593 US80459301A US2002124962A1 US 20020124962 A1 US20020124962 A1 US 20020124962A1 US 80459301 A US80459301 A US 80459301A US 2002124962 A1 US2002124962 A1 US 2002124962A1
- Authority
- US
- United States
- Prior art keywords
- atmospheric pressure
- pressure plasma
- wafer
- electrode
- etching reactor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000001020 plasma etching Methods 0.000 title claims abstract description 14
- 238000012545 processing Methods 0.000 claims abstract description 19
- 239000000203 mixture Substances 0.000 claims abstract description 14
- 239000007789 gas Substances 0.000 claims description 26
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 4
- 239000001301 oxygen Substances 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 2
- 239000001307 helium Substances 0.000 claims 3
- 229910052734 helium Inorganic materials 0.000 claims 3
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims 1
- 239000001257 hydrogen Substances 0.000 claims 1
- 229910052739 hydrogen Inorganic materials 0.000 claims 1
- TXEYQDLBPFQVAA-UHFFFAOYSA-N tetrafluoromethane Chemical compound FC(F)(F)F TXEYQDLBPFQVAA-UHFFFAOYSA-N 0.000 claims 1
- 238000000034 method Methods 0.000 description 46
- 235000012431 wafers Nutrition 0.000 description 45
- 210000002381 plasma Anatomy 0.000 description 38
- 230000008569 process Effects 0.000 description 33
- 229920002120 photoresistant polymer Polymers 0.000 description 18
- 239000000758 substrate Substances 0.000 description 10
- 238000004380 ashing Methods 0.000 description 8
- 238000011109 contamination Methods 0.000 description 5
- 239000012530 fluid Substances 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 238000012864 cross contamination Methods 0.000 description 4
- 238000005530 etching Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 3
- 229910052731 fluorine Inorganic materials 0.000 description 3
- 239000011737 fluorine Substances 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 239000010409 thin film Substances 0.000 description 3
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000005485 electric heating Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 230000032258 transport Effects 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000003570 air Substances 0.000 description 1
- 210000004027 cell Anatomy 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000002894 chemical waste Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003203 everyday effect Effects 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 239000005357 flat glass Substances 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000005468 ion implantation Methods 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003631 wet chemical etching Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32431—Constructional details of the reactor
- H01J37/32798—Further details of plasma apparatus not provided for in groups H01J37/3244 - H01J37/32788; special provisions for cleaning or maintenance of the apparatus
- H01J37/32816—Pressure
- H01J37/32825—Working under atmospheric pressure or higher
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32009—Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources
- H01J37/32082—Radio frequency generated discharge
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/67—Apparatus specially adapted for handling semiconductor or electric solid state devices during manufacture or treatment thereof; Apparatus specially adapted for handling wafers during manufacture or treatment of semiconductor or electric solid state devices or components ; Apparatus not specifically provided for elsewhere
- H01L21/67005—Apparatus not specifically provided for elsewhere
- H01L21/67011—Apparatus for manufacture or treatment
- H01L21/67017—Apparatus for fluid treatment
- H01L21/67063—Apparatus for fluid treatment for etching
- H01L21/67069—Apparatus for fluid treatment for etching for drying etching
Definitions
- the present invention generally relates to plasma generation for use in material etching processes, and, more specifically to a reactor for generating a plasma at atmospheric pressure.
- Photoresist is a thin film compound that is applied to a wafer in order to photographically transfer a circuit pattern to the surface of a wafer.
- the photoresist is “developed” with the circuit pattern and then the developed photoresist is used as a mask to selectively define regions of the wafer that will be etched using a chemically-reactive plasma.
- the residual photoresist mask must be removed, or “ashed” off the surface of the wafer, in preparation for the next process step. It is important that removal of all the photoresist material from the wafer be done in this ashing step, to avoid contamination in subsequent process steps.
- Present systems for providing the wafer ashing process include wet processes, done using solvents, and dry processes accomplished by oxidation of the photoresist layer using ozone or oxygen-containing plasmas.
- Wet photoresist removal steps generate chemical waste, which must be disposed of properly.
- dry processes, such as plasma ashing involve the use of a vacuum chamber in which the plasma is generated, which increases the cost of the equipment.
- a drawback in the use of ozone for photoresist removal is the danger and toxicity of this relatively unstable, noxious gas.
- Plasma ashing is the generally preferred means of photoresist removal.
- each step requires a separate vacuum chamber so that a single process chemistry can be effected in a single chamber, in order to avoid chemical contamination between the steps.
- multiple vacuum chambers are required.
- a wafer must be moved from one chamber to the next. This increases the cost and complexity of the process.
- Multiple process steps are often desirable to use in photoresist ashing as described herein. While the use of multiple processing steps is possible using the prior art, the need for separate vacuum process chambers to accommodate the different chemistries adds to the cost and complexity of the present method.
- the present invention simplifies this process, and provides cleaning ability far superior to the present processes.
- the invention does this at less cost than the conventional technology because of the much higher efficiency attained. It accomplishes these improvements through an atmospheric pressure system that permits it to complete several process steps without the need for vacuum transfers and without the risk of cross contamination. It therefore is an object of the present invention to provide a substrate processing system capable of providing multiple processing steps to a given substrate within a single process enclosure.
- a vacuum chamber is defined as a vacuum-tight, sealed unit capable of being pumped down to a low base pressure and refilled with the process gas for the purpose of generating a plasma. It also would be fitted with necessary vacuum pumps and vacuum gauges and would be constructed of material compatible with vacuum operation.
- An enclosure is defined as leak-tight box that can contain a mix of process gas without contamination from outside air.
- An enclosure does not need the structural stability required for vacuum operation and does not require vacuum pumps, vacuum gauges or load-locks capable of transferring substrates from room air to a vacuum chamber.
- the present invention is loosely related to a recently filed U.S. patent application Ser. No. 09/776,086, filed Feb. 2, 2001, for Processing Materials Inside an Atmospheric-Pressure Radio Frequency Nonthermal Plasma Discharge.
- an atmospheric pressure plasma etching reactor comprises a table for holding and moving a wafer to be processed, with at least one electrode being situated in close proximity to the table and defining an entry for introduction of a gas mixture.
- a radio-frequency voltage connected between the translatable table and the at least one electrode and the gas mixture introduced into the at least one electrode, a plasma is created between the wafer to be processed and the at least one electrode for processing the wafer to be processed as it is moved under the at least one electrode by the table.
- FIG. 1 is a schematical side view of the one embodiment of the present invention showing two processing stations.
- FIG. 2 is an end view of an embodiment of the present invention.
- FIG. 3 is a top view of an embodiment of the present invention.
- the present invention provides plasma processing of substrates and allows each substrate to undergo sequential processing by multiple plasma processors using a single enclosure and a robotic stage.
- the invention can be understood most easily through reference to the drawings.
- FIG. 1 a schematical plan view of one embodiment of the invention is shown where plasma-etching reactor 10 has wafer table 11 for transporting wafer 12 to be processed by an atmospheric pressure plasma jet.
- This atmospheric pressure plasma 13 a is created in atmospheric pressure plasma jet processors 13 , in this figure showing two atmospheric plasma jet processors 13 .
- Atmospheric pressure plasma processors 13 each contain an electrode 14 , shown in side-view in FIG. 1.
- Each electrode 14 has optional temperature control channels 16 and gas baffles 17 .
- An appropriate processing gas is introduced between the two electrodes 14 through gas inlets 18 .
- a plasma 13 a will be created for processing wafer 12 as it is carried through the plasma by wafer table 11 .
- Appropriate temperature control fluids such as air, water or oil, at some desired temperature, are circulated through temperature control channels 16 when necessary to regulate the temperature of electrode 14 .
- it also might be desirable to heat the electrodes 14 by passing a heated fluid through the fluid channels 16 .
- fluid channels 16 are used together with a circulating fluid to control the temperature of gas striking the wafer 12 .
- Wafer table 11 incorporates electric heating rods 19 . Heating rods 19 serve to heat wafer 12 to an appropriate temperature for processing when such action is required. Wafer table 11 is supported by ceramic thermal insulators 20 , which, in turn, are attached to slide carriage 21 . Slide carriage 21 slides along translating slide rails 22 when slide carriage 21 is moved as described below.
- FIG. 2 there can be seen an illustration of an end view of this embodiment of the present invention, where many elements are shown that were hidden in FIG. 1.
- wafer table 11 with wafer is moved under electrode 14 by conventional slide drive screw 23 .
- Slide drive screw 23 can be turned in any convenient manner such as by hand or by a variable-speed motor.
- electric heating rods 19 are also shown, here in cross section, which can be controlled by a thermostat (not shown) to regulate the temperature of wafer 12 for a particular processing regimen.
- FIG. 3 there can be seen a top view of this embodiment of the present invention in which two atmospheric pressure plasma processors are shown.
- This FIG. 3 shows clearly how wafer table 11 transports wafer 12 under electrodes 14 .
- This transport of wafer table 11 is provided by slide drive screw 23 , while sliding along slide rails 22 .
- Also shown are the protective electrically conductive shields 15 inside which the processing of wafer 12 is accomplished.
- FIGS. 1 - 3 illustrate an embodiment of the present invention utilizing two electrodes 14
- the invention is not limited to two electrodes 14 . Any appropriate number could be utilized, from one to many, depending on the processes to be employed for a particular wafer 12 . These electrodes 14 could be employed along with subsequent process steps, including wet rinses, all within the traverse of slide carriage 21 .
- electrode 14 is one electrode and wafer table 11 is the other electrode for connection of the RF energy for creation of a plasma.
- Either one may be rf-powered, and typically, one is grounded. In most cases, it is convenient to have electrode 14 be rf-powered and wafer table 11 be grounded for safety reasons.
- the specific frequency of the RF energy and its voltage level are to be determined for the particular process step to be employed for a particular wafer 12 .
- each electrode 14 can be controlled independently, both with respect to RF energy and process chemistry, while wafer 12 is moved below each electrode 14 .
- a true plasma including ions and electrons, as well as reactive chemical neutral species, exists in the space between electrodes 14 and wafer 12 (FIGS. 1 and 2).
- individual electrodes 14 can be powered differently than others, and can employ different process gas mixtures for particular etching situations.
- one electrode 14 could have a He/CF 4 gas mixture introduced through its gas inlet 18 (FIGS. 1 and 2), while a second electrode 14 could have a He/O 2 gas mixture introduced through its gas inlet 18 .
- a third electrode 14 could be used for passivation of wafer 12 , with use of a gas mixture of He/H 2 for the plasma.
- Such an arrangement may be useful for removal of photoresist that has been “hardened” or carbonized, by exposure to an ion implantation step.
- the intense energy of the ion beam causes a hard “skin” to form on the surface of the photoresist.
- This surface film must be removed using a chemically-aggressive plasma, such as fluorine-containing feedgas (i.e., CF 4 ) and He feedgas plasma, but it is desirable to avoid the use of such plasmas after the surface skin has been removed, and instead use an O 2 and He-based plasma to finish ashing the photoresist.
- the oxygen plasma has better selectivity to silicon (i.e., it will preferentially etch the photoresist without etching the silicon under the photoresist, whereas the fluorine-based plasma will etch both).
- this requires two processes chambers (one for the fluorine plasma and one for the oxygen plasma to avoid cross contamination.
- This invention improves operation of the ashing process by eliminating the need for separate process chambers.
- the present invention processes a single wafer 12 , it is not subject to the accumulation of particles and etch products, as might occur in a solvent cleaning process, such as wet chemical etching systems.
- a solvent cleaning process such as wet chemical etching systems.
- the present invention is inherently both dry and clean. Operational savings result because there is no need to dry wafer 12 or to dispose of solvents.
- the present invention can perform multiple process steps nearly simultaneously, a feat that is not possible with wet processes, and can do so with lower capital equipment cost and with a smaller footprint, or equipment size.
- the present invention offers other advantages over the prior art. First, it eliminates the need for any vacuum equipment, simplifying maintenance of the equipment. Second, it etches or cleans wafers or substrates faster because of high reactive species gas density and in-situ exposure to the plasma, so its throughput is greater. Third, it has the ability to run multiple process steps almost simultaneously, even those requiring different process chemistries, so it results in reduced equipment and process complexity.
- the present invention does not require different vacuum chambers or any vacuum chamber at all. It utilizes a single manipulator to move the wafer through multiple process units, each having the same or different plasma chemistry, and without the associated need for vacuum loadlocks in between. A single process enclosure is used. However, the effect of multiple vacuum chambers is achieved through the use of multiple independently controlled electrodes 14 . The close proximity of electrodes 14 to wafer 12 allows wafer 12 to receive multiple process steps as it progresses under each electrode 14 . Because the gas pressure in the plasma region of each process unit is slightly in excess of atmospheric pressure (to achieve gas flow) the likelihood of cross contamination resulting from gas flow in one process unit entering the adjacent process unit is minimal. Diffusion is slow in this situation, owing to the high pressure operation of each process unit, so cross contamination problems are avoided.
- Applications of the present invention are many and varied. For example, it can be used to etch photoresists, silicon and metal from semiconductor wafers. It can also be used to deposit thin films, including especially large area deposition for thin-film transistor passivation, coatings used for architectural window glass, and deposition of hermetic coatings on magnetic media. Additional applications exist and still others are likely to be discovered through use of the present invention.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Drying Of Semiconductors (AREA)
Abstract
An atmospheric pressure plasma etching reactor has a table holding a wafer to be processed and which moves the wafer to be processed under at least one electrode that is mounted in close proximity to the table and defines an entry of a gas mixture. With a radio-frequency voltage connected between the table and the at least one electrode, a plasma is created between the at least one electrode and the wafer to be processed processing the wafer to be processed as it is moved under the at least one electrode by the table.
Description
- [0001] This invention was made with Government support under Contract No. W-7405-ENG-36 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.
- The present invention generally relates to plasma generation for use in material etching processes, and, more specifically to a reactor for generating a plasma at atmospheric pressure.
- Integrated circuits have become pervasive components of myriad products the world uses everyday. They are found in household products, cell phones, computers, radios and virtually thousands of additional application. Because of the demand for these products, it is imperative that the manufacture of integrated circuits produces efficacious and reliable devices in the most efficient and cost effective manner possible.
- One of the critical steps in the manufacture of integrated circuits is the step of plasma ashing of photoresist. Photoresist is a thin film compound that is applied to a wafer in order to photographically transfer a circuit pattern to the surface of a wafer. The photoresist is “developed” with the circuit pattern and then the developed photoresist is used as a mask to selectively define regions of the wafer that will be etched using a chemically-reactive plasma. After the silicon etching process is complete, the residual photoresist mask must be removed, or “ashed” off the surface of the wafer, in preparation for the next process step. It is important that removal of all the photoresist material from the wafer be done in this ashing step, to avoid contamination in subsequent process steps.
- Present systems for providing the wafer ashing process include wet processes, done using solvents, and dry processes accomplished by oxidation of the photoresist layer using ozone or oxygen-containing plasmas. Wet photoresist removal steps generate chemical waste, which must be disposed of properly. And dry processes, such as plasma ashing, involve the use of a vacuum chamber in which the plasma is generated, which increases the cost of the equipment. A drawback in the use of ozone for photoresist removal is the danger and toxicity of this relatively unstable, noxious gas.
- Plasma ashing is the generally preferred means of photoresist removal. However, because the wafers are individually processed in vacuum, each step requires a separate vacuum chamber so that a single process chemistry can be effected in a single chamber, in order to avoid chemical contamination between the steps. This means that, should multiple process steps be necessary, multiple vacuum chambers are required. Naturally, with multiple vacuum chambers, a wafer must be moved from one chamber to the next. This increases the cost and complexity of the process. Multiple process steps are often desirable to use in photoresist ashing as described herein. While the use of multiple processing steps is possible using the prior art, the need for separate vacuum process chambers to accommodate the different chemistries adds to the cost and complexity of the present method.
- The present invention simplifies this process, and provides cleaning ability far superior to the present processes. The invention does this at less cost than the conventional technology because of the much higher efficiency attained. It accomplishes these improvements through an atmospheric pressure system that permits it to complete several process steps without the need for vacuum transfers and without the risk of cross contamination. It therefore is an object of the present invention to provide a substrate processing system capable of providing multiple processing steps to a given substrate within a single process enclosure. For purposes of discussion herein, a vacuum chamber is defined as a vacuum-tight, sealed unit capable of being pumped down to a low base pressure and refilled with the process gas for the purpose of generating a plasma. It also would be fitted with necessary vacuum pumps and vacuum gauges and would be constructed of material compatible with vacuum operation. An enclosure is defined as leak-tight box that can contain a mix of process gas without contamination from outside air. An enclosure does not need the structural stability required for vacuum operation and does not require vacuum pumps, vacuum gauges or load-locks capable of transferring substrates from room air to a vacuum chamber.
- The present invention is loosely related to a recently filed U.S. patent application Ser. No. 09/776,086, filed Feb. 2, 2001, for Processing Materials Inside an Atmospheric-Pressure Radio Frequency Nonthermal Plasma Discharge.
- It is an object of the present invention to provide substrate processing that is capable of processing multiple substrates in sequence.
- It is another object of the present invention to provide substrate processing that is capable of using different plasma chemistries within the same enclosure.
- Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
- To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, an atmospheric pressure plasma etching reactor comprises a table for holding and moving a wafer to be processed, with at least one electrode being situated in close proximity to the table and defining an entry for introduction of a gas mixture. Wherein, with a radio-frequency voltage connected between the translatable table and the at least one electrode and the gas mixture introduced into the at least one electrode, a plasma is created between the wafer to be processed and the at least one electrode for processing the wafer to be processed as it is moved under the at least one electrode by the table.
- The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:
- FIG. 1 is a schematical side view of the one embodiment of the present invention showing two processing stations.
- FIG. 2 is an end view of an embodiment of the present invention.
- FIG. 3 is a top view of an embodiment of the present invention.
- The present invention provides plasma processing of substrates and allows each substrate to undergo sequential processing by multiple plasma processors using a single enclosure and a robotic stage. The invention can be understood most easily through reference to the drawings.
- In FIG. 1, a schematical plan view of one embodiment of the invention is shown where plasma-
etching reactor 10 has wafer table 11 for transportingwafer 12 to be processed by an atmospheric pressure plasma jet. Thisatmospheric pressure plasma 13 a is created in atmospheric pressureplasma jet processors 13, in this figure showing two atmosphericplasma jet processors 13. Atmosphericpressure plasma processors 13, each contain anelectrode 14, shown in side-view in FIG. 1. Eachelectrode 14 has optionaltemperature control channels 16 andgas baffles 17. An appropriate processing gas is introduced between the twoelectrodes 14 throughgas inlets 18. With the application of a voltage between eitherelectrode 14 and wafer table 11, and introduction of an appropriate gas throughgas inlets 18, aplasma 13 a will be created for processingwafer 12 as it is carried through the plasma by wafer table 11. Appropriate temperature control fluids such as air, water or oil, at some desired temperature, are circulated throughtemperature control channels 16 when necessary to regulate the temperature ofelectrode 14. In some cases, it also might be desirable to heat theelectrodes 14, by passing a heated fluid through thefluid channels 16. In either case,fluid channels 16 are used together with a circulating fluid to control the temperature of gas striking thewafer 12. - Wafer table11 incorporates
electric heating rods 19.Heating rods 19 serve toheat wafer 12 to an appropriate temperature for processing when such action is required. Wafer table 11 is supported by ceramicthermal insulators 20, which, in turn, are attached toslide carriage 21.Slide carriage 21 slides along translatingslide rails 22 whenslide carriage 21 is moved as described below. - Referring now to FIG. 2, there can be seen an illustration of an end view of this embodiment of the present invention, where many elements are shown that were hidden in FIG. 1. Here, it can be seen that wafer table11 with wafer is moved under
electrode 14 by conventionalslide drive screw 23.Slide drive screw 23 can be turned in any convenient manner such as by hand or by a variable-speed motor. Also shown, here in cross section, areelectric heating rods 19, which can be controlled by a thermostat (not shown) to regulate the temperature ofwafer 12 for a particular processing regimen. - Turning now to FIG. 3, there can be seen a top view of this embodiment of the present invention in which two atmospheric pressure plasma processors are shown. This FIG. 3 shows clearly how wafer table11
transports wafer 12 underelectrodes 14. This transport of wafer table 11 is provided byslide drive screw 23, while sliding along slide rails 22. Also shown are the protective electrically conductive shields 15 inside which the processing ofwafer 12 is accomplished. - Although the FIGS.1-3 illustrate an embodiment of the present invention utilizing two
electrodes 14, the invention is not limited to twoelectrodes 14. Any appropriate number could be utilized, from one to many, depending on the processes to be employed for aparticular wafer 12. Theseelectrodes 14 could be employed along with subsequent process steps, including wet rinses, all within the traverse ofslide carriage 21. - In the present invention,
electrode 14 is one electrode and wafer table 11 is the other electrode for connection of the RF energy for creation of a plasma. Either one may be rf-powered, and typically, one is grounded. In most cases, it is convenient to haveelectrode 14 be rf-powered and wafer table 11 be grounded for safety reasons. The specific frequency of the RF energy and its voltage level are to be determined for the particular process step to be employed for aparticular wafer 12. - It is to be understood that in utilizing
individual electrodes 14, eachelectrode 14 can be controlled independently, both with respect to RF energy and process chemistry, whilewafer 12 is moved below eachelectrode 14. A true plasma, including ions and electrons, as well as reactive chemical neutral species, exists in the space betweenelectrodes 14 and wafer 12 (FIGS. 1 and 2). - It is a clear advantage of the present invention that
individual electrodes 14 can be powered differently than others, and can employ different process gas mixtures for particular etching situations. For example, oneelectrode 14 could have a He/CF4 gas mixture introduced through its gas inlet 18 (FIGS. 1 and 2), while asecond electrode 14 could have a He/O2 gas mixture introduced through itsgas inlet 18. Aswafer 12 is moved under eachelectrode 14 it is processed for two process steps instead of the one step in the conventional reactor. In this embodiment, athird electrode 14 could be used for passivation ofwafer 12, with use of a gas mixture of He/H2 for the plasma. Such an arrangement may be useful for removal of photoresist that has been “hardened” or carbonized, by exposure to an ion implantation step. The intense energy of the ion beam causes a hard “skin” to form on the surface of the photoresist. This surface film must be removed using a chemically-aggressive plasma, such as fluorine-containing feedgas (i.e., CF4) and He feedgas plasma, but it is desirable to avoid the use of such plasmas after the surface skin has been removed, and instead use an O2 and He-based plasma to finish ashing the photoresist. The oxygen plasma has better selectivity to silicon (i.e., it will preferentially etch the photoresist without etching the silicon under the photoresist, whereas the fluorine-based plasma will etch both). In conventional plasma systems operating in vacuum, this requires two processes chambers (one for the fluorine plasma and one for the oxygen plasma to avoid cross contamination. This invention improves operation of the ashing process by eliminating the need for separate process chambers. - Also, because the present invention processes a
single wafer 12, it is not subject to the accumulation of particles and etch products, as might occur in a solvent cleaning process, such as wet chemical etching systems. Thus the present invention is inherently both dry and clean. Operational savings result because there is no need to drywafer 12 or to dispose of solvents. In addition, the present invention can perform multiple process steps nearly simultaneously, a feat that is not possible with wet processes, and can do so with lower capital equipment cost and with a smaller footprint, or equipment size. - The present invention offers other advantages over the prior art. First, it eliminates the need for any vacuum equipment, simplifying maintenance of the equipment. Second, it etches or cleans wafers or substrates faster because of high reactive species gas density and in-situ exposure to the plasma, so its throughput is greater. Third, it has the ability to run multiple process steps almost simultaneously, even those requiring different process chemistries, so it results in reduced equipment and process complexity.
- As previously mentioned, it was desirable in the use of prior art vacuum-based plasmas, to operate a single process in a single vacuum chamber for each wafer or substrate. This was done because the use of different process chemistries in the same vacuum chamber causes particle contamination to occur, which is a leading cause of defects during wafer processing. As previously mentioned, the use of different process chemistries was helpful in removing hardened, or carbonized, photoresist. Thus, to use different process chemistries and to avoid contamination problems requires that multiple vacuum chambers be used. When multiple vacuum chambers are used, it means that the wafer must be moved from one chamber to the next, requiring extra handling in addition to the extra process steps and the associated time and expense.
- The present invention does not require different vacuum chambers or any vacuum chamber at all. It utilizes a single manipulator to move the wafer through multiple process units, each having the same or different plasma chemistry, and without the associated need for vacuum loadlocks in between. A single process enclosure is used. However, the effect of multiple vacuum chambers is achieved through the use of multiple independently controlled
electrodes 14. The close proximity ofelectrodes 14 towafer 12 allowswafer 12 to receive multiple process steps as it progresses under eachelectrode 14. Because the gas pressure in the plasma region of each process unit is slightly in excess of atmospheric pressure (to achieve gas flow) the likelihood of cross contamination resulting from gas flow in one process unit entering the adjacent process unit is minimal. Diffusion is slow in this situation, owing to the high pressure operation of each process unit, so cross contamination problems are avoided. - Applications of the present invention are many and varied. For example, it can be used to etch photoresists, silicon and metal from semiconductor wafers. It can also be used to deposit thin films, including especially large area deposition for thin-film transistor passivation, coatings used for architectural window glass, and deposition of hermetic coatings on magnetic media. Additional applications exist and still others are likely to be discovered through use of the present invention.
- The foregoing description of the embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.
Claims (10)
1. An atmospheric pressure plasma etching reactor comprising:
a table for holding and moving a wafer to be processed;
at least one atmospheric pressure plasma processor, said at least one atmospheric pressure plasma processor having an electrode situated in close proximity to said table, and defining an entry for introduction of a gas mixture;
wherein with a radio-frequency voltage connected between said table and said electrode of said least one atmospheric pressure plasma processor and said gas mixture introduced into said at least one atmospheric pressure plasma processor, a plasma is created between said wafer to be processed and said electrode of said at least one atmospheric pressure plasma processor for processing said wafer to be processed as it is moved under said at least one atmospheric pressure plasma processor by said table.
2. The atmospheric pressure plasma etching reactor described in claim 1 further comprising temperature control channels in said least one atmospheric pressure plasma processor.
3. The atmospheric pressure plasma etching reactor described in claim 1 further comprising baffles for distributing said gas mixture throughout said least one atmospheric pressure plasma processor.
4. The atmospheric pressure plasma etching reactor described in claim 1 further comprising controllable heating elements in said table.
5. The atmospheric pressure plasma etching reactor described in claim 1 further comprising a motor for moving said table under said at least one electrode.
6. The atmospheric pressure plasma etching reactor as described in claim 1 wherein said least one atmospheric pressure plasma processor comprises one atmospheric pressure plasma processor.
7. The atmospheric pressure plasma etching reactor as described in claim 1 wherein said at least one atmospheric pressure plasma processor comprises two atmospheric pressure plasma processors.
8. The atmospheric pressure plasma etching reactor as described in claim 1 , wherein said gas mixture comprises helium and carbon tetrafluoride.
9. The atmospheric pressure plasma etching reactor as described in claim 1 , wherein said gas mixture comprises helium and oxygen.
10. The atmospheric pressure plasma etching reactor as described in claim 1 , wherein said gas mixture comprises helium and hydrogen.
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/804,593 US20020124962A1 (en) | 2001-03-12 | 2001-03-12 | Atmospheric pressure plasma etching reactor |
PCT/US2002/007265 WO2002073666A1 (en) | 2001-03-12 | 2002-03-12 | Atmospheric pressure plasma etching reactor |
CA002440328A CA2440328A1 (en) | 2001-03-12 | 2002-03-12 | Atmospheric pressure plasma etching reactor |
US10/208,124 US20030213561A1 (en) | 2001-03-12 | 2002-07-29 | Atmospheric pressure plasma processing reactor |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/804,593 US20020124962A1 (en) | 2001-03-12 | 2001-03-12 | Atmospheric pressure plasma etching reactor |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/208,124 Continuation-In-Part US20030213561A1 (en) | 2001-03-12 | 2002-07-29 | Atmospheric pressure plasma processing reactor |
Publications (1)
Publication Number | Publication Date |
---|---|
US20020124962A1 true US20020124962A1 (en) | 2002-09-12 |
Family
ID=25189357
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/804,593 Abandoned US20020124962A1 (en) | 2001-03-12 | 2001-03-12 | Atmospheric pressure plasma etching reactor |
Country Status (3)
Country | Link |
---|---|
US (1) | US20020124962A1 (en) |
CA (1) | CA2440328A1 (en) |
WO (1) | WO2002073666A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040045578A1 (en) * | 2002-05-03 | 2004-03-11 | Jackson David P. | Method and apparatus for selective treatment of a precision substrate surface |
US20080000497A1 (en) * | 2006-06-30 | 2008-01-03 | Applied Materials, Inc. | Removal of organic-containing layers from large surface areas |
US11780174B2 (en) | 2017-11-07 | 2023-10-10 | University College Dublin, National University Of Ireland | Surface preparation |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE68922244T2 (en) * | 1988-06-06 | 1995-09-14 | Japan Res Dev Corp | Process for performing a plasma reaction at atmospheric pressure. |
JP2691018B2 (en) * | 1989-04-24 | 1997-12-17 | 住友電気工業株式会社 | Plasma etching method |
JPH0817171B2 (en) * | 1990-12-31 | 1996-02-21 | 株式会社半導体エネルギー研究所 | Plasma generator and etching method using the same |
US6006763A (en) * | 1995-01-11 | 1999-12-28 | Seiko Epson Corporation | Surface treatment method |
JPH08250488A (en) * | 1995-01-13 | 1996-09-27 | Seiko Epson Corp | Device and method for plasma treatment |
JP3598602B2 (en) * | 1995-08-07 | 2004-12-08 | セイコーエプソン株式会社 | Plasma etching method, liquid crystal display panel manufacturing method, and plasma etching apparatus |
JP3753194B2 (en) * | 1995-12-14 | 2006-03-08 | セイコーエプソン株式会社 | Plasma processing method and apparatus |
JP3899597B2 (en) * | 1997-01-30 | 2007-03-28 | セイコーエプソン株式会社 | Atmospheric pressure plasma generation method and apparatus, and surface treatment method |
-
2001
- 2001-03-12 US US09/804,593 patent/US20020124962A1/en not_active Abandoned
-
2002
- 2002-03-12 WO PCT/US2002/007265 patent/WO2002073666A1/en not_active Application Discontinuation
- 2002-03-12 CA CA002440328A patent/CA2440328A1/en not_active Abandoned
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040045578A1 (en) * | 2002-05-03 | 2004-03-11 | Jackson David P. | Method and apparatus for selective treatment of a precision substrate surface |
US20070246064A1 (en) * | 2002-05-03 | 2007-10-25 | Jackson David P | Method of treating a substrate |
US20080000497A1 (en) * | 2006-06-30 | 2008-01-03 | Applied Materials, Inc. | Removal of organic-containing layers from large surface areas |
US11780174B2 (en) | 2017-11-07 | 2023-10-10 | University College Dublin, National University Of Ireland | Surface preparation |
Also Published As
Publication number | Publication date |
---|---|
CA2440328A1 (en) | 2002-09-19 |
WO2002073666A1 (en) | 2002-09-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20030213561A1 (en) | Atmospheric pressure plasma processing reactor | |
US9659792B2 (en) | Processing systems and methods for halide scavenging | |
EP0776032B1 (en) | Plasma etching method | |
KR101385346B1 (en) | Methods and apparatus for in-situ substrate processing | |
US20090151870A1 (en) | Silicon carbide focus ring for plasma etching system | |
US20070051471A1 (en) | Methods and apparatus for stripping | |
JPH05121386A (en) | Plasma washing method of substrate surface, photo-resist-plasma washing method of wafer and washing device for substrate surface | |
WO2007117741A2 (en) | A reduced contaminant gas injection system and method of using | |
JPH065567A (en) | Method and apparatus for removing damage beneath surface of semiconductor material by plasma etching | |
KR20080109888A (en) | Post-etch treatment system for removing residue on a substrate | |
US6596123B1 (en) | Method and apparatus for cleaning a semiconductor wafer processing system | |
US20070218197A1 (en) | Vacuum processing system and method of making | |
US20020124962A1 (en) | Atmospheric pressure plasma etching reactor | |
KR101994918B1 (en) | Substrate processing apparatus and substrate processing method | |
JPH08195382A (en) | Semiconductor manufacturing device | |
JP2005012217A (en) | Semiconductor manufacturing apparatus | |
JP4405236B2 (en) | Substrate processing method and substrate processing apparatus | |
JPH09129611A (en) | Etching | |
CN114203506B (en) | Plasma processing device and method thereof | |
KR100323598B1 (en) | Plasma etching method | |
JP2005064120A (en) | Apparatus and method for plasma treatment | |
JP3437557B2 (en) | Plasma ashing method | |
JPH09312283A (en) | Processing device | |
JPS5946127A (en) | Method and apparatus for chemical reaction of gas |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: REGENTS OF THE NUNIVERSITY OF CALIFORNIA, THE, NEW Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SELWYN, GARY S.;HENINS, IVARS;SNYDER, HANS;REEL/FRAME:011966/0212;SIGNING DATES FROM 20010312 TO 20010313 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |
|
AS | Assignment |
Owner name: ENERGY, U. S. DEPARTMENT OF, DISTRICT OF COLUMBIA Free format text: CONFIRMATORY LICENSE;ASSIGNOR:CALIFORNIA, UNIVERSITY OF;REEL/FRAME:013445/0303 Effective date: 20020103 |