47211 A7 B7 五、發明說明（） 發明領域： (請先閱讀背面之注意事項再填寫本頁) 本發明係關於半導體製造裝置等所使用之低溫泵，特別 是關於用以防止其外表面結露之機構。 發明背景： 低溫菜已廣汎被使用作為用以使半導體製造裝置之處理 室等成為超高真空之裝置。低溫泵係為藉極低溫將氣體分 子予以凝結、吸附以進行真空吸引之冷凍積入式之真空 泵。 如第1圖所示’ 一般之低溫泵1係為二段構造，主要由 被冷卻至5 0〜8 0 k之第1階段板體2捕集水蒸氣，由被冷 卻至1 0〜2 0 k之第2階段板體3將氬氣或氮氣等予以凝結 吸附。又’在第2階段板體3表面上，為了更有效率的捕 集氦氣等分子’ 一般慣例係在表面上黏接活性炭。 經濟部智慧財產局員工消費合作社印製 如此因低溫泵1係採用將氣體分子予以積入之方式之 故，在使用一段期間後，排氣能力將降低。相關情況下， 將常溫或其以上之溫度之循環用氣體，例如氮氣等惰性氣 體導入泵内部’將低溫之板體2、3升溫至常溫附近為止， 將積於内部之氣體分子與循環用氣體共同排出之外部之作 業’即所謂之循環作業，乃有其進行之必要。 然而’低溫泵1在通常運作時，其内部係為超高真空之 故’即使内部之板體2、3成為極低溫，因真空斷熱效果使 得外殼4表面幾乎不會冷卻。惟，將循環用氣體導入外殼4 内部後’循環用氣體成為熱傳達媒體，循環開始後，熱被 第2頁 1紙張尺度適用中國國家標準（CNS)Al規格（210 X 297公楚) ~~------- 47211 1、發明說明（ 外殼4被急速冷卻。於是 傳導至仍為極低溫之板體2、3 造成低溫泵1之外表面結露。 通常低溫系_ 1係附凰、&仏 付屬於控制用之電子機器，而安裝有低 溫泵1之半導體製造裝 、装置♦上亦安裝有各種電子機器。 故，若低溫泵1之外类品站喻 _ 卜表面結露’該水分會附著於電子機 器，有妨礙正常運轉之虞。 般係於半導體製造裝置上安裝有漏水檢知裝置之 故’結露造成的水分使漏水檢知裝置作動，有可能會使半 導體製造裝置緊急停止。 本案發明之目的係提供一新穎之低溫泵，其可抑制乃至 防止循環時之結露。 發明概述： 為達成上述目的，本發明之低溫泵之特徵在於具備：外 殼；板體，其係設於外殼内將氣體分子予以凝結吸附者； 循環機構，其係將循環用氣料人外“，將被吸附 體之氣體分子予以氣化，再與該循環用氣體—起排出至外 經 濟 部 智 慧 財 產 局 員 工 消 費 合 作 社 印 製 殼外部者··以及氣體供給機構，其係將循環用氣體供給至 外殼外表面之特定部分者。 氣體供給機構最好係為將循環機構所由外殼排出之循環 用氣體吹附至外殼外表面之特定部分之噴嘴等機構。如 此，將所排出之循環用氣體吹附至外殼後，該部分因被氣 體被覆而與大氣隔絕。又，因由外殼所排出之循環用氣體 非常乾燥且溫度較高，故可防止或抑制吸附有循環用氣體 第3頁 本紙張尺度適用中國國家標準（CNS)A^規格（210 X 297公釐） 經濟部智慧財產局員工消費合作社印製 472113 A7 _B7_ 五、發明說明（） 之部分發生結露問題。 氣體供給機構係由：包圍住外殼之罩；以及將由循環機 構自外殼排出之循環用氣體供給至罩與外殼之間之空間之 機構所構成。於該情況下，外殼全體被完全與大氣隔絕之 故，可完全防止結露。又，因一般由外殼排出之循環用氣 體之溫度比大氣之冰點高之故，罩之外表不會結露。 又，氣體供給機構亦可由：包圍外殼之罩；以及為了在 罩及外殼之間之空間導入循環用氣體而在罩上設置之氣體 導入璋所構成。於該情況下，循環用氣體在被氣體導入埠 導入罩與外殼之間之空間後，被導入前述外殼内。 又，亦可具備加熱機構，在由氣體供給機構將循環用氣 體供給至外殼外表面之特定部分前，將循環用氣體予以加 熱0 本發明之另一目的係為提供一低溫泵之循環方法，其係 將具有外殼及設於外殼内將氣體分子予以凝結吸附之板體 之低溫泵予以循環之方法，其係包含：第1步驟，即將循 環用氣體導入外殼内，將板體上所及附之氣體分子予以氣 化再與該循環用氣體共同排出於外殼外部者；及第2步 驟，即在第1步驟之實施中將循環用氣體供給至前述外殼 之外表面之特定部分者。 本發明之上述及其他特徵或優點茲參照圖式說明於後。 圖式之簡單說明： 第1圖：習知之一般的低溫系·之概略圖。 第4頁 本紙張尺度適用中國國家標準（CNS)A^規格（210 X 297公釐） n n 1^1 n n I n n i n i 1 一°'* * n I d fn n n 1 ' (請先閱讀背面之注意事項再填寫本頁) 472113 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（） 第 2圖：本發明之低溫 栗之較佳實施形態之概略圖。 第 3圖：本發明之低溫 聚之其他實施形態之概略圖》 第 4圖：本發明之低溫泵之另— 其他實施形態之概略 圖號#照說明： 1 低溫泵 2 低溫板體 3 低溫板體 4 外殼 10 低溫泵 12 外殼 14 輻射熱遮蔽板體 16 第2階段板體 18 閥 2 0 冷凍機 2 2 清除埠 24 循環用氣體供給源 26 循環用氣體管線 2 8 閥 3 0 加熱機構 3 2 排氣埠 3 4 閥 3 5 概略抽取管線 3 6 概略抽取泵· 3 8 排氣管線 40 喷嘴 42 閥 44 加熱機構 5 0 處理室 5 2 閘閥 60 罩 62 氣體導入埠 64 排氣埠 66 排氣管線 菸明詳細說明： 以下參照圖面對本發明之較佳實施例予以詳細說明。於 第2圖~第4圖中，對相同或相當部分附註以相同符號，而 第5頁 — II 裝！ — 111 訂--------線 (請先閱讀背面之注意事項再填寫本頁) j ,u * · ▲ > \ 丁 I l s T E L 4 i 47211 A7 B7 經 濟 部 智 慧 財 k 局 員 工 消 費 合 作 社 印 製 五、發明說明（ 不予重複說明。 第2圖係為本發明之低溫泵之較佳實施形態之概略圖。 該低溫泵1 0具備：一端開放另一端封閉之圓筒狀之外毅 12，配置於該外殼12内部之杯狀之輻射熱遮蔽板14 ’以 及配置於其内側之第2階段板體16。輻射熱遮蔽板丨4之 開口部分安裝有閥18，其與輻射熱遮蔽板14共同構成第 1階段板體。輻射熱遮蔽板體14及第2階段板體16連接 於設於外殼1 2外部之冷凍機2 0，遮蔽板14係被冷卻至 50〜80k，第2板體16係被冷卻至1〇〜20k之極低溫。 又，用以將低溫泵1 0予以循環之循環機構具備：清除 埠2 2，其係形成於外殼1 2將惰性氣體等之循環用氣體於 内部予以清除者；及循環用氣體供給源（圖示實施形態中 為氮氣供給源）2 4，其係經由閥2 8以及循環用氣體管線 26而與該清除埠22連接者。於循環用氣體管線26上設有 用以加熱循環用氣體之加熱機構3 0。又，循環機構具備設 於外殼1 2之排氣埠3 2。該排氣埠3 2經由閥3 4連接於旋 轉泵等概略抽取泵36。 自排氣埠3 2與閥3 4之間分岐延伸出排氣管線3 8，於 其前端安裝有用以將來自外殼12之氣體吹附至外殼丨2之 外表面之喷嘴4 0。該喷嘴4 0至少係被固定於可將氣體吹 附於容易結露的部分之安裝位置上，第2圖雖只圖示1 個，但亦可設置複數個喷嘴以對外殼1 2全體進行吸附。符 號4 2係進行排氣管線3 8之開閉之閥。 上述構造之低溫泵10係經由閘閥52連接於如半導體 第6頁 本紙張尺度適用中國國家標準（CNS)Ai規格（210 X 297公釐） III! — — ]— — — — — — ----I I I I ^ - - - ------ (請先閲讀背面之注意事項爯填寫本頁) 472113 經濟部智慧財產局員工消費合作社印製 A7 ___ B7_____ 五、發明說明（） 製造裝置之處理室50等而使用。在進行處理室50内之真 空吸引之情況，使概略抽取泵3 6作動’減壓至某程度為止 後’將閥3 4予以關閉，如前所述，將第1階段板體1 4、 18冷卻至50〜80k，第2階段板體16冷卻至1〇〜20k» 藉此，在第一階段板體1 4、1 8主要凝結吸附水蒸氣，在第 二階段板體16主要凝結吸附氧、氮、氬等。於是處理室 50内之氣體變稀薄，可造成最大為l〇-|0Torr之超高真 空。 如此在板體14、1 6、1 8上吸附了多量的氣體分子後， 排氣能力降低至所期望之程度以下，而有循環之必要。循 環方法係與習知相同，停止冷凍機2 0，將閘閥5 2及？管 線3 5之閥3 4關閉’並且將循環用氣體管線2 6之閥2 8及 排氣管線3 8之閥4 2打開。接著由氮氣供給源2 4供給氮 氣（循環用氣體），由加熱機構3 0加熱後，自清除埠2 2 向外殼2内邵清除。藉此對低溫之板體1 4、1 6、1 8上所 吸附之氣體分子施予氮氣之熱能，氣體分子被散放至外殼 12内部。該氣體分子與氮氣一起由排氣埠32排出。 在該循環中，特別是在初期階段中，第丨階段板體 1 4、16及第2階段板體1 6仍為極低溫之故，氮氣成為導 熱媒體，外殼1 2成為低溫。因此外殼i 2之外表面有結露 之虞。惟，本實施形態中，外殼丨2之排氣埠3 2所排出之 氣體經由排氣管線3 8自噴嘴4 〇噴出之故，可防止或抑制 結露。即’嘴嘴40所喷出之氣體在外殼12之外表面形成 氣體之被膜，妨礙大氣與外| 12《直接接觸。且，雖由外 第7頁 (請先閱讀背面之注意事項再填寫本頁) -裝--------訂---------線 經濟部智慧財產局員工消費合作社印製 472113 A7 -—---—— -_B7__ 五、發明說明（） 殼1 2所排出之氣體係包含水蒸氣等者，但其量係極為微少 且係非常乾燥之氣體之故，可防止或減輕外殼1 2表面結 露。又’—般而言，循環用氣體通過外殼12内之各種部 位’由排氣崞3 2排出時之氣體溫度係為大氣之冰點以上， 藉此亦可發揮防止結露之效果。又，在排氣氣體之溫度低 之情況下’以在排氣管線38中設置適當的加熱機構44將 排氣氣體加熱為佳。 第3圖為本發明之其他實施形態。於該實施形態中，以 密閉之罩60圍住外殼12 ’在罩6〇之氣體導入埠62上連 接來自外殼1 2之排氣管線3 8。於該構造中，外殼1 2係由 罩6 0與大氣隔絕之故’可完全防止結露。又，被導入罩 6 〇與外殼1 2之間之空間之排氣氣體係為較高溫之故（在 其為低溫之情況下，以加熱機構4 〇予以加熱），亦可防止 罩60之外表面結露。被導入罩6〇内之排氣氣體自罩60 之排氣.埠6 4經排氣管線6 6放出至大氣中。此時，有必要 依排氣氣體之種類送至稀釋裝置或熱分解裝置等之處理裝 置（未圖示）予以適當處理。 又’如第4圖所示’在將來自循環用氣體供給源24之 高溫的循環用氣體送至罩60之氣體導入槔62之後，亦可 將該循環用氣體自清除埠2 2向外殼1 2之内部清除。該構 造係利用清除前之循環用氣體係為高溫者。又，由排氣埠 3 2所排出之氣體係被送至與習知構造相同之排氣概略抽取 管線3 5。 如上所述’依本發明’可防止或減輕在低溫泵之循環中 _ 第8頁 本紙張尺度適用中國國家標準（CNS〉A4規格（210 X 297公釐） - ----- — — — — I-裝 i ---I--訂---------線 ' (請先閱讀背面之注意事項再填寫本頁) 472113 A7 _B7_ 五、發明說明（） 所可能發生之結露。藉此，可防止結露所造成之水滴對周 邊之精密機器、電子機器之不良影響，又可防止漏水檢知 裝置錯誤作動。 又，本發明不拘限於上述實施形態，未超出本發明之精 神或範圍之變形或變更自然係包含於本發明之内。 (請先閱讀背面之注意事項耳填寫本頁) 經濟部智慧財產局員工消費合作社印製 _第9頁 本紙張尺度適用中國國家標準（CNS)Ai規格（210 X 297公釐）47211 A7 B7 V. Description of the invention () Field of invention: (Please read the precautions on the back before filling out this page) This invention relates to cryogenic pumps used in semiconductor manufacturing equipment, etc., especially to prevent dew condensation on its outer surface. mechanism. Background of the Invention: Cryogenic dishes have been widely used as devices for making ultra-high vacuum in processing chambers and the like of semiconductor manufacturing devices. The cryopump is a cryopreservation type vacuum pump that condenses and adsorbs gas molecules by extremely low temperature for vacuum suction. As shown in Figure 1, the general cryopump 1 has a two-stage structure. The first stage plate 2 that is cooled to 50 to 80 k is used to capture water vapor, and it is cooled to 10 to 20. In the second stage plate k, argon, nitrogen, or the like is condensed and adsorbed. Also, on the surface of the plate 3 in the second stage, in order to more efficiently capture molecules such as helium gas, it is common practice to adhere activated carbon to the surface. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. Because the cryopump 1 uses a method of accumulating gas molecules, the exhaust capacity will be reduced after a period of use. In related cases, introduce a circulating gas at room temperature or above, such as nitrogen, into an inert gas inside the pump. 'Raise the low-temperature plates 2 and 3 to near normal temperature, and collect the gas molecules and circulating gas accumulated inside. The external work that is collectively discharged ', the so-called cyclic work, is necessary for its implementation. However, "the cryopump 1 has an ultra-high vacuum inside during normal operation", even if the inner plates 2 and 3 become extremely low temperature, the surface of the casing 4 is hardly cooled due to the vacuum heat insulation effect. However, after the circulation gas is introduced into the inside of the casing 4, the circulation gas becomes a heat transfer medium. After the cycle is started, the heat is applied to the paper size on page 2 according to the Chinese National Standard (CNS) Al specification (210 X 297). ------- 47211 1. Description of the invention (The casing 4 is rapidly cooled. It is then conducted to the plates 2 and 3 which are still extremely low temperature, which causes condensation on the outer surface of the cryopump 1. Generally, the low temperature system _ 1 is attached to the phoenix, & 仏 付 is an electronic device for control, and semiconductor manufacturing equipment and devices equipped with the cryopump 1 are also equipped with various electronic devices. Therefore, if the products other than the cryopump 1 stand _ _ Surface condensation on the surface Moisture may adhere to electronic equipment, which may prevent normal operation. Generally, a leak detection device is installed on a semiconductor manufacturing device. The moisture caused by condensation causes the leak detection device to operate, which may cause the semiconductor manufacturing device to stop immediately. The purpose of the invention of this case is to provide a novel cryopump which can suppress or even prevent dew during circulation. Summary of the invention: To achieve the above-mentioned object, the cryopump of the present invention is characterized by having: Plate body, which is set in the shell to condense and adsorb gas molecules; Circulation mechanism, which circulates gas materials outside the human body, to vaporize the gas molecules of the adsorbed body, and then with the cycle gas- The gas is supplied to a specific part of the outer surface of the casing, and is supplied to the outside of the printed housing of the employee's consumer cooperative of the Intellectual Property Bureau of the Ministry of Foreign Economic Affairs. The gas supply mechanism is preferably a circulation mechanism. The circulation gas discharged from the casing is blown to a specific part of the outer surface of the casing by a nozzle or the like. In this way, after the exhausted circulation gas is blown to the casing, the portion is covered by the gas and is isolated from the atmosphere. Also, The circulation gas discharged from the casing is very dry and the temperature is high, so it can prevent or suppress the adsorption of circulation gas. Page 3 This paper applies the Chinese National Standard (CNS) A ^ size (210 X 297 mm) Ministry of Economy Printed by the Intellectual Property Bureau's Consumer Cooperative 472113 A7 _B7_ V. Condensation has occurred in the part of the description of the invention. : A cover that surrounds the housing; and a mechanism that supplies the circulation gas discharged from the housing by the circulation mechanism to the space between the cover and the housing. In this case, the entire housing is completely isolated from the atmosphere, which can be completely prevented Condensation. In addition, because the temperature of the circulating gas discharged from the casing is generally higher than the freezing point of the atmosphere, dew condensation will not occur on the surface of the cover. The gas supply mechanism may also include: a cover that surrounds the casing; In the interspace, a circulation gas is introduced and a gas introduction 设置 provided on the cover. In this case, the circulation gas is introduced into the space between the cover and the housing through the gas introduction port, and then is introduced into the housing. It may also be provided with a heating mechanism to heat the circulation gas before the circulation gas is supplied to a specific part of the outer surface of the housing by the gas supply mechanism. Another object of the present invention is to provide a circulation method of a cryopump, which is A method for circulating a cryopump having a casing and a plate provided in the casing to condense and adsorb gas molecules, the method includes: In the second step, the circulation gas is introduced into the casing, and the gas molecules attached to the plate are vaporized and then discharged together with the circulation gas to the outside of the casing; and the second step is to implement the first step in the implementation of the first step. The circulation gas is supplied to a specific part of the outer surface of the aforementioned casing. The above and other features or advantages of the present invention are described below with reference to the drawings. Brief description of the drawings: Figure 1: A general schematic diagram of a conventional general low temperature system. Page 4 This paper size applies to China National Standard (CNS) A ^ size (210 X 297 mm) nn 1 ^ 1 nn I nnini 1 ° '* * n I d fn nn 1' (Please read the note on the back first Please fill in this page again for details) 472113 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention () Figure 2: A schematic diagram of the preferred embodiment of the low temperature chestnut of the present invention. Fig. 3: Schematic diagram of other embodiments of the low temperature polymerization of the present invention "Fig. 4: Another embodiment of the cryopump of the present invention-Schematic drawings of other embodiments #Notes: 1 Cryo pump 2 Cryo board 3 Cryo board Body 4 Housing 10 Cryo pump 12 Housing 14 Radiation heat shielding plate 16 Phase 2 plate 18 Valve 2 0 Refrigerator 2 2 Clearing port 24 Recycling gas supply source 26 Recycling gas line 2 8 Valve 3 0 Heating mechanism 3 2 Row Gas port 3 4 Valve 3 5 Outline extraction line 3 6 Outline extraction pump 3 8 Exhaust line 40 Nozzle 42 Valve 44 Heating mechanism 5 0 Process chamber 5 2 Gate valve 60 Cover 62 Gas introduction port 64 Exhaust port 66 Exhaust line smoke Detailed description: The preferred embodiments of the present invention will be described in detail below with reference to the drawings. In Figures 2 to 4, the same or equivalent parts are marked with the same symbols, and Page 5 — II is installed! — 111 Order -------- line (please read the precautions on the back before filling in this page) j, u * · ▲ > \ 丁 I ls TEL 4 i 47211 A7 B7 Staff of the Ministry of Economic Affairs, Smart Finance k Printed by the Consumer Cooperative 5. Description of the invention (not repeated). Figure 2 is a schematic diagram of a preferred embodiment of the cryopump of the present invention. The cryopump 10 is equipped with a cylindrical shape with one end open and the other closed. Wai Yi 12, a cup-shaped radiant heat shielding plate 14 'arranged inside the outer shell 12 and a second stage plate 16 arranged inside the same. The opening portion of the radiant heat shielding plate 丨 4 is equipped with a valve 18, which is connected with the radiant heat shielding plate. 14 together constitutes the first stage plate. The radiant heat shielding plate 14 and the second stage plate 16 are connected to the refrigerator 20 located outside the housing 12 and the shielding plate 14 is cooled to 50 ~ 80k. The second plate The 16 series is cooled to an extremely low temperature of 10 to 20k. The circulation mechanism for circulating the cryopump 10 is provided with a clearing port 22, which is formed in the casing 12 and is used to circulate inert gas such as inert gas. Those who remove it internally; and supply source of circulating gas In the embodiment, it is a nitrogen supply source) 24, which is connected to the cleaning port 22 through a valve 28 and a circulation gas line 26. The circulation gas line 26 is provided with a heating mechanism 3 for heating the circulation gas 0. The circulation mechanism includes an exhaust port 3 2 provided in the housing 12. The exhaust port 32 is connected to a rough extraction pump 36 such as a rotary pump via a valve 34. The self-exhaust port 32 and the valve 34 Jianfenqi extends out of the exhaust line 38, and a nozzle 40 is installed at the front end to blow the gas from the shell 12 to the outer surface of the shell 丨 2. The nozzle 40 is fixed at least to be able to blow the gas At the installation position where the condensation is easy, although only one is shown in the second figure, a plurality of nozzles may be provided to adsorb the entire housing 12. The symbol 4 2 is a valve for opening and closing the exhaust line 38. The cryopump 10 with the above structure is connected to the semiconductor via the gate valve 52. The paper size of this paper applies Chinese National Standard (CNS) Ai specification (210 X 297 mm) III! — —] — — — — — —- --IIII ^--------- (Please read the precautions on the back first, fill out this ) 472113 The Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs prints A7 ___ B7_____ V. Description of the invention () Manufacturing equipment processing room 50 and so on. When the vacuum suction in the processing room 50 is performed, the rough extraction pump 36 is operated. 'After decompression to a certain degree', valve 3 4 is closed. As described above, the first stage plates 14 and 18 are cooled to 50 to 80k, and the second stage plate 16 is cooled to 10 to 20k. » Thus, in the first stage, the plates 14 and 18 are mainly condensed and adsorbed with water vapor, and in the second stage, the plates 16 are mainly condensed and adsorbed with oxygen, nitrogen, argon, and the like. As a result, the gas in the processing chamber 50 becomes thinner, which can cause a super high vacuum of 10- | 0 Torr at the maximum. After a large amount of gas molecules are adsorbed on the plates 14, 16, 18 in this way, the exhaust capacity is reduced to a desired level or less, and circulation is necessary. The cycle method is the same as the conventional one. Stop the freezer 2 0, the gate valve 5 2 and? The valve 3 4 of the pipeline 3 5 is closed 'and the valve 2 8 of the circulation gas line 26 and the valve 4 2 of the exhaust line 38 are opened. Next, nitrogen gas (recycling gas) is supplied from the nitrogen supply source 24, and after being heated by the heating mechanism 30, it is removed from the cleaning port 2 2 to the inside of the casing 2. In this way, the thermal energy of nitrogen is applied to the gas molecules adsorbed on the low-temperature plates 14, 16, 18, and the gas molecules are dissipated inside the casing 12. The gas molecules are discharged from the exhaust port 32 together with nitrogen. In this cycle, especially in the initial stage, the plate bodies 1, 4, 16 and 16 of the second stage are still extremely cold, so nitrogen becomes the heat-conducting medium, and the shell 12 becomes low temperature. Therefore, there is a possibility of dew condensation on the outer surface of the casing i 2. However, in this embodiment, the gas discharged from the exhaust port 32 of the casing 2 is ejected from the nozzle 40 through the exhaust line 38, so that condensation can be prevented or suppressed. That is, the gas ejected from the mouthpiece 40 forms a gas film on the outer surface of the casing 12, preventing the atmosphere from coming into direct contact with the outside | 12 ". And, although it is from page 7 (please read the precautions on the back before filling this page) Printed 472113 A7 ------------- -_B7__ 5. Explanation of the invention () The gas system discharged from the shell 12 includes water vapor, etc., but its amount is very small and it is a very dry gas, which can prevent Or reduce the condensation on the surface of the casing 12. Also, generally speaking, the temperature of the gas when the circulating gas passes through various parts in the casing 12 and is discharged from the exhaust gas 32 is at least the freezing point of the atmosphere, thereby preventing the effect of dew condensation. When the temperature of the exhaust gas is low, it is preferable to provide an appropriate heating mechanism 44 in the exhaust line 38 to heat the exhaust gas. Fig. 3 is another embodiment of the present invention. In this embodiment, a closed cover 60 surrounds the casing 12 ', and the gas introduction port 62 of the cover 60 is connected to the exhaust line 38 from the casing 12. In this configuration, the casing 12 is isolated from the atmosphere by the cover 60, which can completely prevent dew condensation. In addition, the exhaust gas system introduced into the space between the cover 60 and the housing 12 has a high temperature (in the case of a low temperature, it is heated by the heating mechanism 40), which can prevent the outside of the cover 60. Dew on the surface. The exhaust gas introduced into the cover 60 is discharged from the exhaust port 64 of the cover 60 to the atmosphere through the exhaust line 66. At this time, it is necessary to send it to a processing device (not shown) such as a diluting device or a thermal decomposition device according to the type of the exhaust gas, for proper processing. Also, as shown in FIG. 4, after the high-temperature circulating gas from the circulating gas supply source 24 is sent to the gas introduction 槔 62 of the cover 60, the circulating gas can be removed from the port 2 2 to the casing 1. 2 of the internal clear. This structure uses the circulating gas system before cleaning as the high temperature. In addition, the gas system discharged from the exhaust port 32 is sent to an exhaust gas general extraction line 35 having the same structure as the conventional one. As described above, 'according to the present invention' can prevent or mitigate in the cycle of the cryopump _ page 8 This paper size applies the Chinese national standard (CNS> A4 specification (210 X 297 mm)--------- — I-install i --- I--order --------- line '(Please read the precautions on the back before filling this page) 472113 A7 _B7_ V. Description of the invention () Condensation that may occur In this way, it is possible to prevent the adverse effects of water droplets caused by condensation on surrounding precision and electronic equipment, and to prevent the leak detection device from malfunctioning. Also, the present invention is not limited to the above embodiments, and does not exceed the spirit of the present invention or Variations or changes in the scope are naturally included in the present invention. (Please read the precautions on the back first and fill out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs_Page 9 This paper size applies Chinese national standards (CNS ) Ai size (210 X 297 mm)