TW592789B - A gas decomposition apparatus - Google Patents

The present invention provides a gas decomposition apparatus, which comprises: a housing; a first inlet pipe positioned in one end of the housing for transporting at least one gas produced after processes; a detector positioned in the first inlet pipe for detecting at least one concentration of the gas; a second inlet pipe and a reaction gas supply device for exporting at least one reaction gas and regulating the output amount of the reaction gas; a chemical reaction region connected directly or indirectly with the first inlet pipe and the second inlet pipe, the chemical reaction between the gas produced after processes and the reaction gas occurs in the chemical reaction region; and a outlet pipe connected with the chemical reaction region for discharging at least one gas produced by the chemical reaction.

592789 五、發明說明（l) 發明之領域 本發明係一種反應後產生之氣體的解離裝置，尤指一 種能自動控制其所輸送的反應氣體流量以完全解離該等反 應後之氣體的解離裝置。 背景說明 現在廣泛應用在半導體製程上的餘刻技術，主要有兩 種：一種是濕式蝕刻（W e t E t c h i n g )，另一種是乾式蝕刻 (Dry Etching)。前者乃是利用化學藥液來溶解半導體晶 片表面之薄膜以進行蝕刻，而後者則係利用活性很強的氣 體分子，使之與被餘刻薄膜產生反應，並於形成揮發性 (Vo 1 at i le)高的生成物後，再以真空系統抽離排出設備之 外。乾式蝕刻技術大都使用含有氟化碳的電漿 (Fluorocarbon Plasma)來執行，例如以蝕刻矽基底來 說’便會於姓刻艙中通入四氟化碳（Carb〇ri 一592789 V. Description of the invention (l) Field of the invention The present invention is a dissociation device for the gas generated after the reaction, especially a dissociation device capable of automatically controlling the flow rate of the reaction gas delivered by it to completely dissociate the gas after the reaction. Background note Nowadays, the remaining etching technology widely used in semiconductor processes mainly includes two types: one is wet etching (Wet Et c h i n g), and the other is dry etching (Dry Etching). The former uses a chemical solution to dissolve the thin film on the surface of the semiconductor wafer for etching, while the latter uses highly reactive gas molecules to react with the film to be etched and form volatile (Vo 1 at i Le) after the high product, it is evacuated out of the equipment by a vacuum system. Most dry etching techniques are performed using a fluorocarbon plasma (Fluorocarbon Plasma). For example, in the case of etching a silicon substrate, ‘carbon tetrafluoride’ (Carbo

Tetrafluonde， CFO’當CF分子被電漿内高能量的電子 轟擊（Bombardment)後即產生各種離子、原子團 (Radicais)，其中原子團F會吸附在底材上，並且和矽發 生反應，變成蒸氣壓很高的s丨F而被蝕刻掉。 方程式（未平衡）可概略表示如下： 子汉應 C F 4 C F 3( g ) + f *( g ) CF *3( g) -> C(s) + F*(g)Tetrafluonde, CFO 'When CF molecules are bombarded with high-energy electrons in the plasma, various ions and atomic groups (Radicais) are generated. Among them, the atomic group F will adsorb on the substrate and react with silicon to become very vapor pressure. High s 丨 F is etched away. The equation (unbalanced) can be roughly expressed as follows: Zi Hanying C F 4 C F 3 (g) + f * (g) CF * 3 (g)-> C (s) + F * (g)

592789 五、發明說明（2)592789 V. Description of Invention (2)

Si(s)+F*(g) - SiF4(g) 在半導體廠中，蝕刻反應後的氣體，諸如三氟化氮 (N F 3)、六氟化鎢（W F 6)、六氟化二碳（C 2F 6)、四氟化矽 (S i F 4)等等，均須經過一次再處理的製程，以避免污染環 境，甚至能夠再回收利用。在習知技術中，通常係以解離 的方式來對上述氣體進行再處理。舉例而言，三氟化氮 (NF3)於加熱之後，會分解為氮氣（N2)與氟氣（F2)，其中氮 氣（N 2)可再與氧氣反應而形成一氧化氮（N 0 )。然而一氧化 氮（N 0 )有致癌之危險且為破壞臭氧層的元兇，因此需要與 u 足夠的氨氣（N Η 3)來產生反應，始能將一氧化氮（NO)再轉 化成無害的氮氣（N2)。另一方面，由三氟化氮（NF 3)分解產 生之氟氣（F2)在遇到水之後，會產生一氟化氫（HF)氣體， 而氟化氫（HF )氣體具有腐蝕性，所以亦必須與一氨氣 (NH3)反應以產生一氟化銨（NH4F)。其中氟化銨（NH4F)係一 可溶於水之弱酸性物質。上述之化學反應方程式如下所 示： 2NF3— N2+3F2 N2+02— 2N0 4NH3+6N0 -> 5 N 2+ 4 Η 20 6HF + 6NH3 - 6NH4F · 習知技術皆係使用人工或半自動的偵測方式來測定蝕 刻反應產生之氣體濃度，然後再藉由流量控制器（MFC)據Si (s) + F * (g)-SiF4 (g) In semiconductor plants, the gases after the etching reaction, such as nitrogen trifluoride (NF 3), tungsten hexafluoride (WF 6), dicarbon hexafluoride (C 2F 6), silicon tetrafluoride (S i F 4), etc., must go through a reprocessing process to avoid polluting the environment and even to be recycled. In the conventional technology, the above-mentioned gas is usually reprocessed in a dissociation manner. For example, after heating, nitrogen trifluoride (NF3) will be decomposed into nitrogen (N2) and fluorine gas (F2). The nitrogen gas (N2) can react with oxygen to form nitrogen monoxide (N0). However, nitric oxide (N 0) is dangerous for carcinogenesis and is the culprit of damaging the ozone layer, so it needs to react with u enough ammonia gas (N 始 3) to convert nitrogen monoxide (NO) into harmless ones. Nitrogen (N2). On the other hand, the fluorine gas (F2) produced by the decomposition of nitrogen trifluoride (NF 3) will produce hydrogen fluoride (HF) gas after encountering water, and hydrogen fluoride (HF) gas is corrosive, so it must also be compatible with An ammonia gas (NH3) is reacted to produce ammonium monofluoride (NH4F). Among them, ammonium fluoride (NH4F) is a weakly acidic substance that is soluble in water. The above chemical reaction equation is as follows: 2NF3— N2 + 3F2 N2 + 02— 2N0 4NH3 + 6N0-> 5 N 2+ 4 Η 20 6HF + 6NH3-6NH4F · All conventional technologies use manual or semi-automatic detection To measure the gas concentration produced by the etching reaction, and then use the flow controller (MFC)

第6頁 592789 五、發明說明（3) 以提供一固定流量的反應氣體（例如上述之氨氣）與蝕刻反 應產生之氣體來產生化學反應。然而，蝕刻反應所產生之 氣體流量可能會隨時間或其他因素而變化，因此習知技術 不易掌握解離反應是否完全，而非常容易產生供應之反應 氣體不足或過量之問題。以三氟化氮之解離反應為例，若 是不足量的氨氣（NH 3)與一氧化氮（NO)反應，可能使得未 參與反應的一氧化氮（N 0 )排出，造成環境污染。反之，若 是過量的氨氣（NH3)與一氧化氮（NO)反應，則會造成資源 浪費。 ► 發明概述Page 6 592789 V. Description of the invention (3) A chemical reaction is generated by providing a fixed flow rate of the reaction gas (such as the ammonia gas mentioned above) and the gas generated by the etching reaction. However, the gas flow rate generated by the etching reaction may change with time or other factors. Therefore, it is difficult for the conventional technology to grasp whether the dissociation reaction is complete, and it is very easy to cause the problem that the supplied reaction gas is insufficient or excessive. Taking the dissociation reaction of nitrogen trifluoride as an example, if an insufficient amount of ammonia (NH 3) reacts with nitric oxide (NO), it may cause the non-reacting nitric oxide (N 0) to be discharged, causing environmental pollution. Conversely, if excessive ammonia (NH3) reacts with nitric oxide (NO), it will cause waste of resources. ► Invention Overview

本發明係提供一種氣體的解離裝置，其包含有：一殼 體，該殼體之一端設有一第一進氣管線，以輸送至少一製 程後之氣體；一偵測器，設於該第一進氣管線，以偵測該 製程後之氣體的至少一濃度值；一第二進氣管線以及一反 應氣體供給器，以輸出至少一反應氣體並調整該反應氣體 的一輸出量；一流量控制計（MFC )，能接收由該偵測器傳 來的氣體濃度訊號，而調整被輸出的該反應氣體的該輸出 量；一化學反應區，與該第一進氣管線和該第二進氣管線The invention provides a gas dissociation device, which comprises: a casing, one end of the casing is provided with a first air inlet line to convey at least one process gas; a detector is disposed on the first An air inlet line to detect at least a concentration value of the gas after the process; a second air inlet line and a reaction gas supplier to output at least one reaction gas and adjust an output amount of the reaction gas; a flow control Meter (MFC), which can receive the gas concentration signal from the detector, and adjust the output of the reaction gas to be output; a chemical reaction zone, the first intake line and the second intake Pipeline

第7頁 592789 五、發明說明（4) 直接或間接相通，以供該製程後之氣體與該反應氣體產生 該化學反應；以及一排氣管線，與該化學反應區相通，用 來排放出該化學反應後之至少一氣體。 由於本發明提供之解離裝置係利用一偵測器自動量測 製程後之氣體的濃度值，並配合一流量控制計來相對控制 反應氣體的輸出量，因此可以避免習知技術中因反應氣體 供應不足或過量產生的環境污染或資源浪費的問題。 發明之詳細說明 請參閱圖一，圖一為本發明提供之氣體的解離裝置30 示意圖。本發明之氣體解離裝置可以應用於半導體製程中 任一製程反應後產生之氣體，在本發明之最佳實施例中， 是將該氣體解離裝置應用於解離蝕刻製程後產生之氣體。 解離裝置3 0包含有一形狀類似一山字型之殼體3 1，一設於 殼體3 1之一端並與一蝕刻機台（未顯示）相連且包含有一用 以輸送該蝕刻製程產生之氣體進氣口 3 4的第一進氣管線 3 2，一設於第一進氣管線3 2上用以偵測該蝕刻製程後之各 氣體的濃度值，並可根據各該濃度值而產生一訊號以傳送 至一流量控制計3 9的偵測器3 5，一與一反應氣體供應機台 (未顯示）相連以輸出一種或一種以上之反應氣體的第二進 氣管線3 6，一設於第二進氣管線3 6上用以調整被輸出之各 該反應氣體之輸出量的反應氣體供給器38，一與第一進氣Page 7 592789 V. Description of the invention (4) Direct or indirect communication for the chemical reaction between the gas after the process and the reaction gas; and an exhaust line communicating with the chemical reaction zone for discharging the At least one gas after a chemical reaction. Since the dissociation device provided by the present invention uses a detector to automatically measure the concentration of the gas after the process, and cooperates with a flow control meter to control the output of the reaction gas relatively, it is possible to avoid the supply of reaction gas in the conventional technology Environmental pollution or waste of resources caused by insufficient or excessive amounts. Detailed description of the invention Please refer to FIG. 1. FIG. 1 is a schematic diagram of a gas dissociation device 30 provided by the present invention. The gas dissociation device of the present invention can be applied to a gas generated after a reaction in any process in a semiconductor process. In a preferred embodiment of the present invention, the gas dissociation device is applied to a gas generated after a dissociation etching process. The dissociation device 30 includes a shell 31 having a shape similar to a chevron. One is disposed at one end of the shell 31 and is connected to an etching machine (not shown) and includes a gas for conveying the etching process. The first air inlet line 32 of the air inlet 34 is provided on the first air inlet line 32 to detect the concentration value of each gas after the etching process, and can generate a value according to each concentration value. The signal is transmitted to a detector 3 5 of a flow control meter 3 9, a second inlet line 36 connected to a reactive gas supply machine (not shown) to output one or more reactive gases, and a set A reaction gas supplier 38 on the second intake line 36 is used to adjust the output of each of the reaction gases to be output.

第8頁 592789 五、發明說明（5) 管線3 2和第二進氣管線3 6相通用以供該蝕刻製程後之氣體 與該反應氣體產生該化學反應的化學反應區4 0，一設於殼 體3 1之另一端並與化學反應區4 0相通且包含有一用以排放 出該化學反應後之氣體之排氣口 4 6的排氣管線4 4。 其中，流量控制計（MFC ) 3 9可直接設於反應氣體供給 器38之上，用來調整被輸出的該反應氣體的輸出量，而解 離裝置3 0可另包含有一設於殼體3 1底部的水槽4 2，用來緩 衝及降低部分蝕刻反應後之氣體的溫度並能溶解部分氣 體，一設於水槽4 2與化學反應區4 0下方且具有孔洞之隔板 4 1，用以隔開排氣管線4 4與第一進氣管線3 2、第二進氣管 線3 6，一設於排氣管線4 4中之水霧區4 8，用來進行一洒水 或喷水的動作，以降低該化學反應後之氣體溫度。 管線 之外 用以 訊號 氣管 學反 號而 收由 號， 本發明 32中用 ，並可 偵測水 而傳送 線44中 應後之 傳送該 偵測器 並將该 之解離裝置 來偵測該# 於水槽4 2中 槽4 2中之水 至流量控制 再設置一第 任一氣體的 訊號至流量 35、該PH偵 等訊號分別 3 0除了 刻製程 另裝設 溶液的 計39。 二偵測 濃度值 控制計 測裝置 傳送至 上述說明中，設於第一進氣 後之氣體濃度值的偵測器3 5 有一 PH偵測裝置（未顯示）， PH值，並產生 此外，解離裝 器（未顯示）， ’並根據该濃 3 9。因此流量 以及該第二偵 該反應氣體供 一相對應之PH 置3 0亦可於排 用以偵測該化 度值產生一訊 控制計3 9能接 測器傳來的訊 給器，以適當Page 8 592789 V. Description of the invention (5) The line 32 and the second inlet line 36 are in common for the chemical reaction zone 40 for the chemical reaction between the gas after the etching process and the reaction gas. The other end of the casing 31 is in communication with the chemical reaction zone 40 and includes an exhaust line 44 for exhaust ports 46 for exhausting the gas after the chemical reaction. Among them, the flow control meter (MFC) 39 can be directly set on the reaction gas supplier 38 to adjust the output amount of the reaction gas to be output, and the dissociation device 30 can further include a housing 3 1 A water tank 42 at the bottom is used to buffer and reduce the temperature of some of the gas after the etching reaction and can dissolve part of the gas. A partition plate 41 provided with a hole below the water tank 42 and the chemical reaction zone 40 is used to isolate Open the exhaust line 4 4 and the first intake line 3 2, the second intake line 36, and a water mist area 48 arranged in the exhaust line 44 to perform a water spraying or spraying action. In order to reduce the temperature of the gas after the chemical reaction. It is used outside the pipeline to signal tracheology and reverse. It is used in the present invention 32, and can detect water and the detector in the transmission line 44 transmits the detector and the dissociation device to detect the # 于The water to flow control in the water tank 4 2 and the water tank 4 2 is provided with a signal of the first gas to the flow rate 35, and the signals such as the pH detector are respectively 30. In addition to the engraving process, a solution meter 39 is installed. Two detection concentration value control measurement devices are transmitted to the above description. The detector for the gas concentration value after the first intake air is provided. 3 5 There is a PH detection device (not shown), and the PH value is generated. Device (not shown), 'and according to the thick 3 9. Therefore, the flow rate and the second detection of the reaction gas for a corresponding PH setting of 3 0 can also be used in the row to detect the degree value to generate a signal control meter 39 can receive the signal from the tester, to appropriate

第9頁 592789 五、發明說明（6) 地調整各該反應氣體的輸出量。其中偵測器3 5以及第二偵 測器可為一傅立葉轉換紅外線光譜儀（F T I R )、一核磁共振 儀（NNR )、一氣相層析儀（GC )或一紫外線紅外線光譜儀 (UVIR)。 現以在背景說明中所提及之三氟化氮的解離反應為例 來做說明，由於三氟化氮解離形成之氮氣（N 2)可再與氧氣 反應而形成一氧化氮（N 0 )，因此本發明係先藉由設於第一 進氣管線3 2的偵測器3 5，偵測出經由第一進氣管線3 2所輸 送進本發明之解離裝置3 0之一氧化氮（NO )的濃度值，並相 對應的產生一濃度訊號，以將一氧化氮（N 0 )的濃度值傳回 至流量控制計3 9，使流量控制計3 9能控制反應氣體供給器 38，以精確調整所供給之氨氣（NH3)的量。 接著氨氣（N Η 3)便經由第二進氣管線3 6而被輸送至化 學反應區40，致使氨氣（ΝΗ3)與一氧化氮（NO)產生化學反 應。其中，當氨氣（NH 3)、一氧化氮（NO)與其生成物於經 過水槽4 2時，水槽4 2的水有降低其溫度的作用。隨後該等 反應後之氣體會接續通過排氣管線4 4，此時便可藉由排氣 管線44上所設置之第二偵測器來偵測排氣管線44中之該化 學反應後之各氣體的第二濃度值，作一重複確認，並相對g 應的產生一第二濃度訊號，以將該第二濃度值傳送至流量胃 控制計3 9，俾使流量控制計3 9能跟據最終反應結果來調整 反應氣體供給器3 8所供給的反應氣體流量，冀以完全解離 /Page 9 592789 V. Description of the invention (6) Adjust the output of each reaction gas. The detector 35 and the second detector may be a Fourier transform infrared spectrometer (FTIR), a nuclear magnetic resonance instrument (NNR), a gas chromatograph (GC), or an ultraviolet infrared spectrometer (UVIR). Taking the dissociation reaction of nitrogen trifluoride mentioned in the background note as an example, the nitrogen (N 2) formed by the dissociation of nitrogen trifluoride can be reacted with oxygen to form nitric oxide (N 0). Therefore, the present invention first detects a nitrogen oxide (a nitrogen oxide) delivered to the dissociation device 30 of the present invention via the first intake line 32 by the detector 35 provided in the first intake line 32. NO) concentration value, and correspondingly generates a concentration signal to return the concentration value of nitric oxide (N 0) to the flow control meter 39, so that the flow control meter 39 can control the reaction gas supplier 38, To precisely adjust the amount of ammonia gas (NH3) supplied. The ammonia gas (N Η 3) is then transported to the chemical reaction zone 40 through the second intake line 36, so that the ammonia gas (NΗ3) and the nitrogen monoxide (NO) generate a chemical reaction. Among them, when ammonia gas (NH 3), nitric oxide (NO), and its products pass through the water tank 42, the water in the water tank 42 has the effect of lowering its temperature. Then the reacted gases will continue to pass through the exhaust line 44. At this time, the second detector in the exhaust line 44 can be used to detect each of the chemical reactions in the exhaust line 44. The second concentration value of the gas is repeatedly confirmed, and a second concentration signal is generated corresponding to g to transmit the second concentration value to the flow rate control meter 39, so that the flow rate control meter 39 can follow the data The final reaction result is to adjust the flow rate of the reaction gas supplied by the reaction gas supplier 38 so as to completely dissociate /

第10頁 592789 五、發明說明（7) 蝕刻製程後之氣體並且避免反應氣體可能過量的問題。最 後該等反應後之氣體會經過水霧區4 8接受洒水再降低溫度 的步驟，並經由排氣口 4 6排出。 此外，三氟化氮除了會分解成氮氣（N 2)外，亦會分解 成氟氣（F2)並進而產生一氟化氫（HF)氣體，由於氟化氫 (HF )氣體係為一強酸性物質，所以亦必須與氨氣（NH 3)進 行酸驗中和反應，以產生一氟化銨（N H 4F )，其中氟化敍 (N H 4F )係為一可溶於水之弱酸性物質，因此在通過水槽4 2 時會造成一 PH值的變化，而PH值的變化可以被設於水槽之 __ PH偵測器所偵測到，並且產生一，PH值訊號，該PH值的變化 傳至流量控制計3 9之後，使流量控制計3 9可以據以控制反 應氣體供給器3 8所供給的反應氣體流量。 本發明之解離裝置係至少於進氣管線設有一偵測器， 以自動偵測蝕刻製程後之氣體的濃度值，另可於排氣口設 置一第二偵測器，以偵測化學反應後之任一氣體的一濃度 值，並可於水槽另設有一 PH偵測裝置，以偵測水槽之一 PH 值，因此流量控制計可以接收來自各偵測裝置之訊號，並 將該訊號傳送至該反應氣體供給器，進而以最適當的方式 來調整該反應氣體的輸出量。. ^ 相較於習知技術，本發明係利用各偵測裝置以及一流 量控制計，以自動調整一反應氣體的供應流量，致使蝕刻Page 10 592789 V. Description of the invention (7) The gas after the etching process and avoid the problem that the reaction gas may be excessive. In the end, the reacted gases will pass through the water mist area 48 to be sprayed with water and then the temperature will be lowered, and then discharged through the exhaust port 46. In addition, nitrogen trifluoride will not only decompose into nitrogen (N 2), but also decompose into fluorine (F2) and generate hydrogen fluoride (HF) gas. Because the hydrogen fluoride (HF) gas system is a strongly acidic substance, It is also necessary to perform an acid test neutralization reaction with ammonia gas (NH 3) to produce ammonium monofluoride (NH 4F). Fluoride (NH 4F) is a weakly acidic substance that is soluble in water. When the water tank 4 2, a PH value change will be caused, and the PH value change can be detected by the __ PH detector set in the water tank, and a PH value signal is generated, and the PH value change is transmitted to the flow rate. After controlling the meter 39, the flow rate control meter 39 can be used to control the flow rate of the reaction gas supplied by the reaction gas supplier 38. The dissociation device of the present invention is provided with a detector at least in the air inlet line to automatically detect the concentration value of the gas after the etching process, and a second detector may be provided at the exhaust port to detect the chemical reaction A concentration value of any gas, and a PH detection device can be set in the water tank to detect a PH value of the water tank, so the flow control meter can receive signals from each detection device, and send the signal to The reaction gas supplier further adjusts the output amount of the reaction gas in an optimal manner. ^ Compared with the conventional technology, the present invention uses various detection devices and a first-rate quantity control meter to automatically adjust the supply flow of a reactive gas to cause etching.

第11頁 592789 五、發明說明（8) 製程後之氣體能夠與反應氣體充分反應，而不至於有部分 的蝕刻製程後之氣體或部分的反應氣體，在未充分反應之 前，即由排氣口所排出，故能有效避免環境污染或資源浪 費的問題。 以上所述僅為本發明之較佳實施例，凡依本發明申請 專利範圍所做之均等變化與修飾，皆應屬本發明專利之涵 蓋範圍。Page 11 592789 V. Description of the invention (8) The gas after the process can fully react with the reaction gas, so that there is no part of the gas after the etching process or part of the reaction gas. Before the gas is not fully reacted, it is exhausted It can effectively avoid the problems of environmental pollution or waste of resources. The above description is only a preferred embodiment of the present invention, and any equivalent changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the scope of the invention patent.

第12頁 592789 圖式簡單說明 圖示之簡單說明 圖一為本發明之氣體的解離裝置示意圖。 圖示之符號說明 31殼體 3 4進氣口 3 8反應氣體供給器 41隔板 4 4排氣管線 4 8水霧區 3 9流量控制計 30 解離裝置 32 第一進氣管線 36 第二進氣管線 40 化學反應區 4 2 水槽 46 排氣口 3 5 偵測器Page 12 592789 Brief description of the diagram Brief description of the diagram Figure 1 is a schematic diagram of the gas dissociation device of the present invention. Explanation of symbols in the figure 31 housing 3 4 air inlet 3 8 reaction gas supplier 41 partition 4 4 exhaust line 4 8 water mist area 3 9 flow control meter 30 dissociation device 32 first inlet line 36 second inlet Gas line 40 Chemical reaction zone 4 2 Water tank 46 Exhaust port 3 5 Detector