TW541358B - Method for dry cleaning metal etching chamber - Google Patents

Abstract

In accordance with the present invention, a method is provided for dry cleaning a processing chamber. This method comprises the step of introducing a first cleaning process gas into the processing chamber. A plasma is formed from the first cleaning process gas and maintained for a first time period. Next, repeating the step of introducing the cleaning process gas, a second cleaning process gas is introduced into the processing chamber and maintained the plasma for a second time period. As a result, the present invention is capable of removing polymer built up on the processing chamber's interior surfaces to achieve a high yield and maintaining throughput of the substrates in the plasma processing system.

Description

541358 No. 90109615 said Amendment 5. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to a method for cleaning a process reaction chamber, in particular to a method for dry cleaning a metal etching reaction chamber.疋 2. [Prior art] In the manufacturing process of semiconductor integrated circuits, optical lithography technology is often used. In today's technology, on the semiconductor wafer, Yori 4 丨 2 1 1 ^ ^ ^ resistance. Exposure to ultraviolet light to transfer the required image to # f3. However, the solubility of the exposed area of the photoresist will be changed. In the use of :::: shadow, the designed pattern is fixed on the wafer. It is difficult to perform the baking step to perform the subsequent process steps. In the world, after the world circuit contains electricity, the loss of the widgets will usually occur, and the side wall sheet passes through the component phase of these residual patent cases. In addition, in the manufacturing of high molecular residual ion implantation retentate is included in the continuous process of the conventional technology, the integration process is formed, and its components are formed. When the photoresist layer is removed, the structure and the element layer are formed. These residues are the implantation residues and the residues are the residues caused by the crystals. No. 9 5 0 2 4 7 2 is an ion implantation for the design pattern system. The laminate is removed from the wafer, and the residue above the wafer surface may be caused by the part itself. Retentions come in two forms. After that, the original photoresist layer was removed by ashes (as s h and exposed behind) by the body circuit but the photoresist for the ionizing element i ng.

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Amendment :: Species such as (Kun, Butterfly or Dish) produce organometallic materials without species] 疋 Side wall 咼 Molecular residues. The formation of such residues can help form the required etching geometry. But it is not intentional, especially in the plasma environment containing fluorine, so that the polymer cannot be removed. These residues contain perfluorinated or chlorouorinated organic materials. The commonly used photoresist removal method is to use wet oxidative developers (wes oxidative developers) wsuifuric acid-hydrogen peroxide / valley liquid and plasma ashing). The wet oxidation developer f is dangerous and easily causes contamination on the wafer surface. Plasma deashing is performed relatively slowly and causes electronic damage to the wafer. In addition, in U.S. Patent No. 5,6 7 8, 2 丨 4, it is mentioned that in the use of a single crystal RIE tool, the wafer is moved into the single crystal RIE tool and an etching step is performed, wherein the RIE tool includes a In order to monitor the etching step, nd0w. In general, the main pollutants in RIE tools are the south molecules produced by R 丨 e reactants and coated on the end point detection w 丨 nd〇w, these polymers such as CF4. Or CHFS and can be The material to be etched is, for example, silicon or siIlcon. These polymers are formed on the inner wall of the detection, which limits the number of wafers that can be etched without losing the end point signal. The dry-etching section 疋 is used to measure the polymer on the inner surface of window. Communication 541358 — — — 卽 109615 Rev. 5th, the description of the invention (3) Division-$ 疋 by wet removal of isopropyl alcohol (is〇pr〇pyl aic〇h〇l) as a polymer . However, it takes eight hours to remove the polymer in this way, which is very time consuming and costly. # # Further, it is pointed out in US Patent No. 5, 6 0, 68 1 to decompose a side protective film (s 丨 dewa u protection film) dominated by S i 〇χ using a dilute nitrogen acid solution ^ and in the subsequent In the step, an oxygen-based plasma step is used to remove the resist mask of the organic material. However, even with the dilute hydrofluoric acid solution and the use of an oxygen plasma, the effect of removing the side wall protective layer is less accessible. The semiconductor manufacturing process includes a series of smaller and smaller integrated circuit fabrications. The geometric dimensions have become smaller and smaller, and the power of I4 has been limited. In the process, when pollutants are deposited in the reaction, it becomes a semiconductor. When the reaction chamber is subjected to metal etching on the inner wall of the semiconductor reaction chamber, effective and economical cleaning is an important method. String of different chemical and physical processes on the substrate. As the critical dimension uniformity and accuracy of the semiconductor elements are maintained, the inner wall of the chamber is more and more carried out in the reaction chamber of the semiconductor process. When it accumulates a certain number of processes, very disadvantageous factors come. Shape can become particularly pronounced. In manufacturing, in general, the yield rate and overall efficiency should be improved. The reaction chamber for integrated circuit components can be etched using photoresist. The energy (RF Power) used to etch the electrical frequency of the plasma is added to the reaction chamber. Pick the selection layer. When a wireless

III or more electrodes

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When the reaction chamber pollutants are deposited, distribution neglects the formation of clean counterproducts. When the residual pollutants are peeled off, the two methods of good performance for efficient and non-destructive components and the well-known dry-cleaning chamber are performed on semiconductor wafers and then accumulated in the inner plate (GDP) of the reaction chamber. The chamber will cause secondary and no lack of regular cleaning procedures, migration to the substrate will cause pollution rate lethality (yield kill damage to the reaction chamber cleaning method, quality. Clean in place (i η-si clean (dryc 1 eaning)) During the etching process, the wall and the gas are scattered in the parts. The time-reliable process and accumulation in the reaction chamber. Especially when the high rate) can exceed 1 and can usually enhance tu clean) (also wet clean 1¾ molecular plate (gas for a long time) The molecules produced on the inner wall of the defect produce 0 ° / 0. The production process is carried out in a clean-in-place process, and the process gas is pumped out of the reaction chamber, and one or more cleaning process gases are passed into the reaction chamber. Then provided An energy causes the gas to react with any residue that accumulates on the interior surface of the reaction chamber. The residue on the interior surface of the reaction chamber reacts with the cleaning process gas to form Annoying by-products are simultaneously removed from the reaction chamber with part of the unreacted clean gas. Two = the cleaning process can resume the general process steps. In contrast to the in-situ cleaning process, which can keep the reaction chamber closed, the wet cleaning process should The chamber is hermetically vacuumed, and the internal surface of the reaction chamber is manually wiped

541358 ___Case No. 90109615_ ± V. Description of the invention (6) Amendment

surface. Such surname cleaning procedures have a more severe impact on yields than dry cleaning procedures. When performing wet cleaning, opening the reaction chamber and using the inside surface of the artificial reaction chamber will result in equipment downtime (d 〇 w η -1 ime) (approximately 1 4 to 16 hour). Before resuming the general process steps, the reaction chamber must reach a re-stable state, which can wipe more heavily because when the high fraction (part ic 1 is reduced. This' accumulates when anti-execution time-consuming cleaning procedures are accumulated to a certain degree. About 9 0 0 0 type of cleaning steps to increase production to achieve this-purpose clean) is not a program. So. In particular, the yield rate is quite similar to that when the electrons accumulate on the inner surface of the reaction chamber. When a power jump occurs, the polymer on the inner surface of the vacuum equipment reaction chamber will be wet-cleaned. Wet cleaning procedures do not completely remove contaminants, and contamination is performed. Usually a period of RF-minutes (approximately 150 RF-hours). Loss due to downtime due to cleaning procedures. It is therefore obvious that it is very important to reduce the yield of reaction chamber wafers. Extending the average cleaning time interval (mean ¥ is urgent. The so-called cleaning means' providing improved seed cleaning of the semiconductor reaction chamber can remove polymer accumulation in the reaction It can maintain the high product of the plasma process system and cause the normal or the software to crash and peel off, and it must be usually used when the thing slows down for a considerable time over time. That is to say, time bet wee: time-consuming wet cleaning method is a method that must be productive on the interior surface of the room.

541358 Case No. 90109615 V. Description of the invention (7) ± _Η Means to modify the content of the invention In view of the above-mentioned background of the invention, the traditional Qing, Qing control method has many disadvantages, the present invention :: the private reaction chamber A method of dry cleaning a substrate for a wafer manufacturing system, such as a substrate. In the method of the present invention, yak burdock is used to clean the process gas in the reaction chamber. Afterwards, it is included by the first person, the first plasma is maintained and the plasma is maintained for the first period of time: a clean process gas, the steps of forming the lice body, the access—the second, the main system, and the heavy Covered with clean, quasi-plasma-receiving gas-Di Shi = Eryibang gas in the reaction chamber, and the polymer fouling ": ΓΓ; Γ removes product accumulated in the reaction ... to the product productivity of the clothing system. Plasma counteracts another aspect of the present invention to clean the process gas. In order to provide a dry cleaning reaction chamber, the present invention is to clean the reaction chamber. J, D. Provide a two-step dry cleaning method of the present invention «ΛΑ A method for reducing the particle exceeding control rate. Is used to provide a purpose according to the above-mentioned one, in a preferred embodiment, the present invention mentions page 11 541358 _ case number 90109615_ year month day_ _ V. Description of the invention (8) A method for dry cleaning a reaction chamber is provided, wherein the reaction chamber includes at least a first electrode and a second electrode. The method of the present invention includes at least steps in which a first cleaning is passed Process gas is in the reaction chamber. A clean process gas forms a plasma and maintains the plasma for a first period of time. Furthermore, the step of introducing the clean process gas is repeated, and a second clean process gas is passed into the reaction chamber, and the plasma is maintained for a first time. Two periods. The above method further includes adding a radio frequency energy to the cleaning process gas to generate a plasma, and about 800 watts of radio frequency energy is added to the first electrode. The method of the present invention further includes adding one energy. About 4 watts are on the second electrode, and this second electrode can also be a substrate support bracket. Therefore, the polymer accumulated on the support rack can also be effectively removed. The above method further includes maintaining the plasma Between the first time period and the second time period, the first cleaning process gas is pumped away from the reaction chamber. As a result, the present invention can remove high-molecular pollutants accumulated on the inner surface of the reaction chamber to improve the yield and maintain the plasma Productivity of the reaction chamber process system. Fourth, Γ luxury force; ^]

'一' ^ I ≦ Λ A Some embodiments of the present invention will be described in detail below. However, in addition to the detailed description, the present invention can also be widely implemented in other embodiments, and the scope of the present invention is not limited, which is subject to the scope of subsequent patents. In a preferred embodiment of the present invention, a dry cleaning process is provided.

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The method of the reaction chamber is first cleaned for a period of time. In addition, the second clean process gas is accumulated in the removal reaction chamber, and a first clean process gas is first passed to form an electro-forged cover and the clean process gas reaction chamber is maintained, and the plasma contamination is maintained. Process gas in the reaction chamber. And maintain the step of the plasma to reach the first, the first to the second period, to first Cang · the first picture, the # and 闰 G6, ', Japan] easy process reaction room 1 0 0 horizontal Cutaway. The reaction chamber 100 may be a worm-etched reaction chamber having a shell 11 1 made of a non-magnetic material 1 1 η λα / ν m ^. And can be ashamed ,. & inner chamber space

1 1 2. The process gas is passed from the gas inlet 1 1 4 to # butterfly and also from ^ ^ ^ ^, i 4 is passed to a rolling body spreading plate 1 1 6. The main function of the gas distribution plate 1 1 6 is a deposition or etching process in which the knife uses Feng to evenly distribute the gas on the wafer to form a uniform sentence. And the gas diffusion plate 116 can be used as a first electrode and connected to a radio frequency energy generator (not shown in the figure) and it is also connected to a substrate support rack 118. And the substrate support rack 1 i 丨 can be used as the second electrode. The semiconductor substrate 20 is placed on the substrate support rack 118 'against the edge ring 22. The u-ring 124 is placed on the edge ring 122. The lifting frame 1 2 6 and the bottom ring 1 2 8 are also used to support the substrate supporting carriage 丨 丨 8. An additional exhaust port 130 is connected to a vacuum unit (not shown) to allow the reaction chamber to evacuate.

In a preferred embodiment, a method for dry cleaning a reaction chamber 100 is provided. The process reaction chamber 100 is a plasma process reaction chamber, especially a metal remaining reaction chamber. During the metal etching process, metal-based contaminants / southern particles are deposited on the inner surface of the reaction chamber in advance. When the last name is carved

Page 13 541358 -09- · 5 ----- Year and month __ V. Description of the invention αο) The performance of the rights is set 'sequentially there will be photoresist-based pollutants / polymers that will accumulate in The inner surface of the reaction chamber to which the metal polymer has been attached. In the method of the present invention, the steps at least include: passing a first cleaning process gas to the reactor; and a cleaning process gas including at least a first flow of oxygen and its flow rate is about 210 to 2 50 per minute. Standard cubic centimeter (SCCM) CM /. And its better flow rate is about 230 standard cubic centimeters per minute (SC, and the pressure in the anti-reaction chamber 100 is about 20 to 40 millitorr (mtorr). 30 millitorr (m t0 rr). Then, it contains a period of time. "Clean the process gas to form a plasma and maintain the plasma for the first time. The first time period when the oxygen is held by the relatively small part is about 10. Between 1 to 14 seconds, the time period of the soil is about 12 seconds. The internal use of radon oxygen as a cleaning process gas can effectively remove the high-resolution surface of the reaction chamber and the high photoresist-based surface. Molecules ', but the effect of repeated fouling is poor for removing metals. Furthermore,' removing metal-based polymers in the reaction process of ^ ^ clean process gas, the second clean process gas: "^ °,". Furthermore, the clean process gas ^^^ minutes (SCCM) ^ " 1L is about 1 40 to 180 standard cubic centimeters per minute (\ between ') and its better flow rate It is about 160% per minute during the second standard period, which is large (% M), and maintains the plasma for a second period. Maintains the plasma for the second second. The counter-employment rate is 8 12 seconds, and the preferred second period is about 10 intervals, and the pressure within ^! = 100 is maintained at about 20 to 40 millitorr (mtorr) while the pressure of the car driver is about 3 0 millitorr (mtοrr).

苐 Page 14 541358 ____ Case No. 90109615_Che Yueyin ____ V. Description of the Invention (11) In another embodiment, the steps of the present invention include at least, first, a clean process gas is passed into the metal etching process reaction chamber 1 0 0 steps, especially the aluminum etching reaction chamber. The cleaning process gas contains at least a mixture of oxygen with a flow rate between about 180 SCCM and 220 SCCM and a gas flow between about 130 SCCM and 170 SCCM. The best flow rates for oxygen and gas are 200 SCCM and 150 SCCM, respectively. Then, a gas is mixed from the cleaning process to form a plasma, and the plasma is maintained for a period of time between about 22 seconds and 28 seconds. The best time to maintain it is about 25 seconds. The pressure in the reaction chamber 100 is maintained between about 20 and 40 millitorr (mt rr), and the preferred pressure is about 30 millitorr (mtorr). The method of the present invention further comprises A radio-frequency energy is used to clean the process gas to generate a plasma, and a radio-frequency energy between about 600 and 1,000 watts is added to the first electrode, and a preferred energy is about 800. watt. Moreover, the method of the present invention further comprises adding an energy between about 2 to 6 watts to the second electrode, and the preferred energy is about 4 watts. Therefore, the plutonium molecules accumulated on the support rack 118 can also be effectively removed. If a sacrificial substrate (also known as a baffle) is placed on the substrate support rack to protect the support rack 118 from damage during the plasma cleaning operation, the energy provided to the second electrode can be approximately It is between 100 watts and 250 watts. Therefore, the present invention can be applied with or without a flap. The above method further includes a step of removing the first clean process gas from the reaction chamber between the first period and the second period when the plasma is maintained.

Page 15 541358 _ Case No. 90109615 V. Description of the invention (12) The second item of the number t test is a particle diagram using traditional technology and the application of the present invention. The number of contaminated particles is based on the number of substrates manufactured as the horizontal axis. From the graph, it can be obtained that after the application of the present invention, the average number of particles is 5 and the control rate can be reduced to 1.0%. The advantages of the present invention are also known. After the application of the present invention, it can pass through more than about 2000 Rf-minute

Sub-wet cleaning, which requires about 90,000 RF-minutes per minute compared with the prior art ^ human wet cleaning greatly improves the average cleaning interval.苴 xianpu P = Lei: device downtime and save a lot of manpower, that is to increase: 'Le ,: the system's output and reduce costs. Yi Jingwang With reference to Figures 4A and 4B, it can be known that the polymer full-ring is more serious than the U-ring after applying the present invention. It can also be known from the polymer accumulation of the "after"? Spreading plate. The chaos of the two-dimensional scattering plate has a car than the prior art gas spreading plate; II. It must be noted that the present invention can be performed in the second phase. : 疋 Depends on the process conditions of the clothing reaction chamber. That is, the present invention =, ϊ ϊ = should respond to the high molecular contamination on the interior surface of the chamber to improve the yield, and: maintain the product productivity of the plasma reaction chamber process system. She can also: The above is only a preferred embodiment of the present invention, and the equivalent scope of the patent application has been changed under the spirit of the limit of the equivalent changes :: within the scope of the patent not disclosed. Decoration, should include In the following applications

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__tl 虎 90】 Ca-q diagram briefly illustrates the first diagram is a cross-sectional view of a simple process reaction chamber; Table; the second diagram is the use of traditional technology and the number of particles after the application of the present invention The third diagram is the use of traditional technology And distance chart;% the average cleaning time after using the present invention, the fourth A picture is a traditional technique of Japanese style; τ, the situation where polymers are deposited on the ring, the fourth B picture is after using the present invention, one, to The situation where the molecules are stacked on the ring is shown in FIG. 5A, which is a situation where the polymer is deposited on the plate when the gas is dispersed by the conventional technique; and the diagram B, which is selected using the present invention. ^ 'Representative symbols for polymer accumulation on the main part of the gas distribution plate: I 0 0 process reaction chamber, II 0 reaction chamber housing 11 2 inside the reaction chamber 541358 _ Case No. 90109615_ year, month and day correction diagram, simple description 1 14 gas inlet I 1 6 Gas diffusion plate II 8 Substrate support bracket 1 2 0 Substrate 1 2 2 Edge ring 1 2 4 U ring 126 Lifting frame 1 2 8 Bottom ring 130 Exhaust port

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Claims (1)

541358 Case No. 90109615 Amendment VI. Scope of Patent Application Maintain the oxygen plasma for a second period of time. 7. The method of claim 6 in the scope of patent application, wherein the process reaction chamber described above includes at least a first electrode and a second electrode. 8. The method according to item 6 of the scope of patent application, wherein the flow rate of the oxygen cleaning process gas is 230 SCCM. 9. The method according to item 7 of the patent application scope, further comprising adding a radio frequency energy to the oxygen cleaning process gas to generate the plasma, and the radio frequency energy of 800 watts is added to the first electrode. . 10. The method according to item 7 of the patent application scope, further comprising applying an energy of 4 watts to the second electrode. 1 1. The method of claim 6 in the scope of patent application, wherein the first period of time is 12 seconds. i 2. The method according to item 6 of the scope of patent application, wherein the second flow rate is 160 SCCM. * 1 3. The method according to item 6 of the patent application range, wherein the second time period is 10 seconds. Page 20 541358 ____ Case No. 90109615_ 6th, the scope of the patent application is amended 1 4 · If the method of the 6th scope of the patent application, the method includes the first time period and the second time period when maintaining the plasma At the same time, the step of removing the oxygen cleaning process gas from the process reaction chamber. 15. The method of claim 6 in the scope of patent application, wherein the reaction chamber of the above process is a metal-engraved reaction chamber. 1 6 · A method for dry cleaning a metal etching reaction chamber, comprising the steps of: passing in an oxygen cleaning process with a flow rate of 230 SCCM, a gas into the metal etch reaction chamber, wherein the metal etching reaction chamber has a first An electrode and a second electrode; performing a radio frequency energy on the oxygen to clean the radon gas with an oxygen plasma; maintaining the oxygen plasma for one second of 12 seconds for the first period to remove Photoresist-based polymer · Pass in one of the gas-cleaning gas-etching reaction chambers with a flow rate of 160SCCM; mad & Heijing performs a radio frequency on the gas-cleaning process gas slurry; and An electric power maintained the plasma for one of 10 seconds. In the second period, a metal-based high-density bearing was formed on the inner surface of the etching chamber. In the gold π. The method of claim 16 in which the above-mentioned radio frequency Page 541 358 Page 22