1259214 九、發明說明： 【發明所屬之技術領域】 本赉明描述一種藉由高溫沈積法自汽相成長單晶體之裝 置與方法。詳言之，該裝置可用於製造由以下各物形成之 大型咼質量之大塊晶體（bulk Crystal): ^碳化矽、b)例如 或A1N之第III族氮化物或c) Sic與第m族氮化物之合金。 【先前技術】 諸如碳化矽（sic)、第in族氮化物（例如氮化鎵（GaN)及氮 化鋁（A1N))之寬帶隙半導體晶體具有若干有吸引力的電及 物理特性以用於快速切換電源裝置及光電子裝置。該等寬 帶隙半導體及其合金自身亦與諸如矽及砷化鎵之其它重要 半導體不g，主要差異在於以下事實··其目前不能在實際 有效及具經濟效益之條件下直接自熔融或液體溶液成長。 相反地，通常藉由將過飽和蒸汽流磊晶沈積至一晶種（seed crystal)上而自汽相成長SiC、GaN或A1N之結晶塊（ing〇t)。 在SiC之狀况下，所開發出的第一種用於製造直徑及長度 足夠製造用於裝置應用之晶圓的半導體等級Sic晶體（亦稱 為結晶塊或晶塊）之方法係昇華法，亦稱為物理汽相傳輸 (pvt)。該方法之核心概念已在1955年由Lely在，，以士匕化 der Deutschen Keramische，Ges· 32_8 Ρ· 229 (1955)” 中引 入，且已在 1978 年由 Tairov 及 Tsvetkov 在” J· Cryst· Growth 52，ρ·146 (1981)中修改以製造一致的半導體等級晶 體，其中可控制諸如多類型及晶體成長速率的重要特性。 簡言之，該方法基於使用一密封坩堝，其中在高溫區與較 92736.doc 1259214 低/皿區之間建立-溫度梯度，其中諸如sic粉末之固態源材 料在高溫區内昇華，而經昇華之物質在低溫區内於晶種上 目础不同集團亦已開發出用於成長A1N及GaN大塊晶體 之昇華法’且亦在研究用於成長GaNA塊晶體之氫化物汽 相蠢晶及液相技術。 如今該昇華法允許直徑為5〇 mm及高達1〇〇 mm之sic晶 圓之製造具有足夠輸入品質及成本以使得可工業製造諸如 LED及Schottky二極體之裝置。 儘管具㈣等成就，“在此昇華⑽巾還存在一些挑 戰及限制。舉例而'r ’只要不能設計出連續饋人機構，則 進料之初始貝里限制連續晶體成長過程之持續時間，且因 此限制了 sa體的長度。舉例而言，—個困難可能為需要控 制變化的昇華速率與在成長過程中所昇華之物質理想配比 的偏差。例如’源材料供應之不穩定性及源進料中溫度分 佈之偏差導致成長速率之偏差及摻雜物質併入之偏差。若 未適當地控制該等偏差，職傾向於對晶體成長方法之良 率產生不利影響。 可藉由進-步改良昇華方法來解決該等挑戰，且在训之 狀況下，用於製造相對較大規模之晶圓的技術之性能係其 工業潛力之指示。 已在19 9 5年由美國專利楚< 一 ⑵寻和弟5,704,985號引入一種替代的工 業上有用之技術，其確奮蔣 貫徒t、了對源材料供應的連續控制1259214 IX. Description of the invention: [Technical field to which the invention pertains] The present invention describes an apparatus and method for growing a single crystal from a vapor phase by a high temperature deposition method. In particular, the apparatus can be used to fabricate bulk crystals of large masses formed from: ^carbonized germanium, b), for example, or a group III nitride of A1N or c) Sic and the mth group Alloy of nitride. [Prior Art] Wide bandgap semiconductor crystals such as bismuth carbide (sic), indium nitride (such as gallium nitride (GaN) and aluminum nitride (A1N)) have several attractive electrical and physical properties for use in Quickly switch power supply units and optoelectronic devices. These wide bandgap semiconductors and their alloys themselves are not related to other important semiconductors such as germanium and gallium arsenide. The main difference lies in the fact that they cannot currently be directly self-melting or liquid solutions under practical and economical conditions. growing up. Conversely, a crystalline block of SiC, GaN or A1N is typically grown from the vapor phase by epitaxial deposition of a supersaturated vapor stream onto a seed crystal. In the case of SiC, the first method developed to produce semiconductor grade Sic crystals (also known as crystalline blocks or ingots) of sufficient diameter and length to fabricate wafers for device applications is sublimation, Also known as physical vapor phase transmission (pvt). The core concept of this method was introduced in 1955 by Lely, der Deutsch Deutschen Keramische, Ges 32_8 Ρ 229 (1955), and was in 1978 by Tairov and Tsvetkov at "J. Cryst· Growth 52, ρ. 146 (1981) is modified to produce consistent semiconductor grade crystals in which important characteristics such as multiple types and crystal growth rates can be controlled. Briefly, the method is based on the use of a sealed crucible in which a temperature gradient is established between the high temperature region and the lower/counter region of 92736.doc 1259214, wherein the solid source material such as sic powder sublimes in the high temperature region and is sublimed The substances in the low temperature region are different on the seed crystals. The group has also developed a sublimation method for growing A1N and GaN bulk crystals' and is also studying the hydride vapor phase stray crystals and liquids used to grow the crystals of the GaNA block. Phase technology. Today, the sublimation method allows the manufacture of sic crystals having a diameter of 5 mm and up to 1 mm to have sufficient input quality and cost to enable industrial fabrication of devices such as LEDs and Schottky diodes. Despite the achievements of (4), "there are some challenges and limitations in sublimation (10). For example, 'r' does not limit the duration of the continuous crystal growth process as long as the continuous feeding mechanism cannot be designed, and Therefore, the length of the sa body is limited. For example, a difficulty may be a deviation between the sublimation rate that needs to control the change and the stoichiometric ratio of the material that is sublimated during the growth process. For example, 'the instability of the source material supply and the source The deviation of the temperature distribution in the material leads to the deviation of the growth rate and the deviation of the doping substance. If the deviation is not properly controlled, the job tends to have an adverse effect on the yield of the crystal growth method. Sublimation methods to address these challenges, and in the context of training, the performance of the technology used to fabricate relatively large-scale wafers is an indication of its industrial potential. It has been in the United States patent Chu in 1959 (1) Xunhedi 5,704,985 introduces an alternative industrially useful technology, which is indeed continually controlling the supply of source materials.
以及自汽相成長長晶體之、、既A 版I，曰力。此種技術一般稱為高溫化 92736.doc 1259214 學汽相沈積（HTCVD)且不同於密封ρντ組態，不同之處在 於：其使用-在源材料供應及材料換雜中提供精確控制之 開放式熱壁(〇penh〇t-wall)組態。詳言之，以經調整之氣沛 形態連續供應成長材料組份中的至少—種，並通過_:: 將其饋人至高溫區域中。此外，在結晶區域下游提供—排 氣裝置以控制沿成長之晶體表面之氣流並排出由結晶處理 產生之副產品。由於此技術在概念上類似於用於成長厚产 為（M至200脾之蟲晶層的CVD技術，所以其可被稱為化^ 汽相沈積(CVD)'然而，如美國專利第5,7〇4,985號及第 6,〇48,398號所教示，為了達到具經濟效益的用於製造大型 大塊晶體之成長速率，HTCVD技術使用比正常CVD方法高 一個數量級之源氣體進料速率及高幾百度之溫度。/呵 舉例而言，在與美國專利第5,7〇4,985號之第一圖式中的 裝置類似之裝置中（圖υ，在Sic之特定狀況下，藉由將晶種 (13)加熱至2250 C之溫度並經由入口 15饋入一含有在載體 氣體中稀釋的0.3 L/min矽烷及(u L/min乙烯之氣體混合 物’而獲得0.5 mm/h之成長速率。 然而，當執行該方法數小時後，在實驗中觀察到· sic亦 圍繞圖1中的晶種基板（13)結晶、結晶至由例如石墨製成之 固持器（12)上及結晶至排氣孔（14)之曝露表面上。在直接位 於晶種（13)附近的表面上，Sic結晶為主要包含6h&i5r多 類型的密集多晶體固體。在排氣孔14之更遠下游處，sic結 晶為稍微較不密集之多晶體晶粒，其通常為針狀且為3c多 類型。密集多晶體沈積可以大約為單晶體結晶速率兩倍之 92736.doc 1259214 速率發生。較不密集之多晶體沈積物甚至成長地更快，最 終在2至4個小時内阻塞氣體出口通道。一旦晶種下游之排 氧通道被充分阻塞，即在源氣體人口 15與排氣埠“之間迅 速形成壓力差。若允許壓力差達到幾毫巴，則發生多類型 及單晶體之結構品質之迅速變差。源氣體亦可開始沿傳導 性比受阻塞之排氣孔14高的通道流動’例如藉由任何諸如 圖1中之1 5的多孔絕緣材料流動。接著，歸因於與矽的反 應，絕緣材料之熱特性迅速變差，此迫使成長中冑。或者， 當排氣通道14在不允許源氣體找到較高傳導性之通道的情 况下變得阻塞時，由於多晶體矽之沈積而導致發生氣體入 導s非快速的堵塞。在此狀況下，由於沒有源氣體可 供應至單晶體而亦需要中斷成長。 因此多晶體固相之寄生沈積導致該系統之災難性的失 控，從而迫使在製造出所#長度之晶體之前停止成長過程。 已在PCT申請案W0 98/14644中提出解決此問題之一試 驗性解決方法。在SiC晶體成長之實例中，該申請案描述一 種衣置，其中由一薄内圓筒25隔離含Si&c之處理氣體與圖 2中的主要加熱元件7。一覆蓋惰性氣體（blanketing inen gas) 被迫在主要加熱元件與内圓筒之間流動，該内圓筒終止於 大約對應於單晶體成長前端之距離處。在單晶體成長前端 之下游，覆盍氣體沿著該主要加熱圓筒之壁而被引導，其 意在於防止或充分減慢SiC多晶體在下游内壁上沈積並減 慢SiC多晶體在晶種固持器13上成長，以使得出口通道 保持通暢。在歐洲專利申請案第787,822 A1號中提出類似解 92736.doc -10- 1259214 =法’其+在_與测。c之間操作之裝置存在與處理氣 力1L平行流動之惰性覆蓋氣體。 =發現在該等文獻中提出的或得自該等文獻之解決方法 亚未將以上所描述之問題解決至達到足夠成長具有數匪 長度之SlC或其它晶體的程度。使用諸如氦或氬之惰性覆蓋 耽體之實驗展示：在單晶體成長前端之下游區域仍出現過 於迅速之多晶體沈積。當使用氦作為覆蓋氣體時，容易得 到甚至更高之多晶體成長速率，而使用氬僅將沈積區域向 下游推進了-段較短的距離。可利用由該覆蓋氣體在其通 過由石墨製成之未塗覆加熱元件時所攜帶的碳之額外通量 及利用該等兩種所考慮之氣體不同的熱傳導性來解釋此意 外、，。果纟虽石夕排氣混合物中，任何額外之碳供應會導致 多晶體sic下游成長之增加。當使用以Sic塗覆之加熱元件了 ⑽察到類似現象。為防止此現象發生’熟習該項技術者 將明瞭應使用由諸如Ta C或N b C之金屬碳化物塗覆之加熱 元件及V ¥來作為改良。該等曝露表面較佳亦將具有較低 表面粗糙度以為多晶體SiC提供較少長晶點（nucleati〇n site)。然而，在導致0.5至！ mm/h之單晶體成長速率的典型 處理條件下，觀察到此種設計僅導致不可控制之多晶體sic 在更下游位置沈積。此對阻塞時間的較小改良並不足以連 續成長若干cm長的晶體。 在其它設計用以成長SiC晶體的先前技術裝置中，並未提 及待成長材料之多晶體形態之寄生沈積的解決方法5在該 等裝置中，將待成長之材料中的至少一個組份作為氣體饋 92736.doc -11 - 1259214 入且將過程之副產品經由坩堝内的開口排出。舉例而古， 歐洲專利554,047 Β1藉由一裝置教示Sic晶體之成長’ 4裝 置使用矽烷與丙烷作為源氣體，該等源氣體在第一反應^ 中反應以形成隨後將在較低壓力昇華區蒸發的Sic顆粒。結 晶過程之副產品及載體氣體僅描述成通過一出口排出。在 1997年申請之美國專利第5,985,024號中揭示了一種裝置， 其中自受熱矽熔融物供應矽蒸汽且將諸如丙烷之碳氫化合 物氣體通過一氣體供應入口供應至成長區。在該裝置中， 成長之SiC結晶塊下游的過量氣體亦僅描述成藉由一過道 或出口渠道自該成長區移除。由於在晶種固持器中或其附 近需要減少的溫度分佈以促進SiC單晶體的成長，咸信該等 過道將不可避免地遭受由Sic多晶體、熱解石墨（pyr〇lytic graphite)或多晶體Si沈積中的任一種所造成的災難性阻 塞。在1995年申請之美國專利第6,〇48,398號中描述了類似 概念，其中結合有碳氫化合物氣體之熔融矽進料可用作源 氣體。過ΐ氟體在晶種固持器之下游排出，該晶種固持器 隨著單晶體成長的進行而被旋轉及拉伸。儘管晶種固持器 之旋轉導致對多晶體沈積物之有益清除作用，但是此種機 械清除導致旋轉機構或晶種固持器中之應力並引起該等元 件開始與之接觸。此可導致上述零件中任何一個的機械失 靈。 在美國專利申請案第2002/0056411 Α1號中討論一種用 於製造SiC結晶塊之高溫汽相沈積設備，其中將成長區域中 氣體混合物的壓力設定為比排氣混合物的壓力高以增加處 92736.doc -12- 1259214 理之良率。可藉由設計該設傷而達成此壓力差，以使得入 口之傳導性比出口之傳導性高。切低傳導㈣置於單晶 體成長區之下游之後’在恒溫下，排氣混合物之減少的壓 f導致寄生多晶體材料之沈積速率減少。此減慢了沿排氣 之傳J·生減v區域下游之通道的任何災難性阻塞。然 而在所引用之申睛案中指出：隨著溫度沿該下游通道降 低，沈積物將再次在被稱為氣體收集器咖s㈣之給定區 域中積聚。防止該等沈積將允許將該過程延續更長時間且 允許製造更長的晶體。此外，在本申請案中，該系統必須 至少在傳導性減少區域之下游部分中以減少之壓力操作。 可需要替代地在成長區及出口區中以大體大氣壓操作該裝 置’此係由於其可有利於整個系統之較高良率及較低成本 兩者。 應注意上述問題的起源係在基礎之意義上，即使以物質 之最大量運輸配置在單晶體成長前端。由於在高溫下進行 成長以促進高成長速率及高結晶品質，所以為了防止表面 被石墨化，在成長前端的下游連續排出至少與受熱之晶體 表面之平衡Si壓力相等之量的Si蒸汽。 【發明内容】 一本發明提供—種用於在—受熱室（稱為晶座或掛禍）中在 高溫下以一成長速率持續一段足夠製造若干毫米長或較佳 若干公分長之晶體的時間自汽相成長Sic、第m族氮化物或 其合金中任一種之單晶體的方法與裝置。 洋σ之’本發明之一目標在於：減慢或消除多晶體及其 92736.doc •13- 1259214 它固體沈積物在單晶體結晶區域下游之形成，以避免晶座 排氣通道因饋入至結晶區域之氣體混合物所造成的局部或 完全堵塞。本發明之一相關目的係控制成長之單晶體之直 徑且防止多晶體材料在其周圍成長，藉此防止在高溫成長 階段或隨後之冷卻階段中的任一階段中產生結構缺陷。 本發明之進一步目標在於：藉由自汽相中移除由結晶區 域下私之受熱部分所釋放的活性金屬元素來降低單晶體成 長中所不欲之金屬雜質的濃度。 為了防止在單晶體成長區域附近及其下游任何區域之表 面上形成所不欲之多晶體沈積物，本發明提議藉由在該等 表面附近引入一具有蝕刻該等沈積物之化學特性的單獨氣 流來降低成長材料中至少一種組份之局部過飽和度。在sic 或GaN晶體成長之狀況下，較佳使用含至少一種鹵族元素 之氣流（諸如氯化氫、氯氣或氫氣與氯氣或氯化氫之混合物） 作為蝕刻劑。自本發明之詳細描述中將易瞭解：其它含諸 士 Br F或I之鹵素的氣體或氣體混合物亦可用於類似目 的。敍刻氣體亦可以此方式分佈以積極控制成長之晶體的 形狀。在以下圖式、描述及申請專利範圍中將明示並描述 本發明之其他較佳特徵及優勢。 【實施方式】 圖3示意展示一種包含基於美國專利第5,7〇4,985、 6,〇39,812及6,048,398號中所描述之概念的11丁(：¥0系統成 長至之改良裝置。此處亦將該裝置描述為本發明的裝置9 本發明可具有與上文所提及之文獻類似的原理構造，但是 92736.doc -14- 1259214 其中所描述的特殊特徵及改良則不同。圖3之裝置適於成長 Sic或第m族氮化物的單晶體。為了簡單起見而示意展示一 些部分，且熟習此項技術者將明瞭：該裝置亦包含諸如大 流量控制器（mass flow controller)、閥門、泵、電子控制器、 淨化器、洗滌系統及其它元件之元件，此在CVD系統是慣 *两溫化學汽相沈積裝置包含外殼1，其由（例如）緊固地安 裝在下部法闌3與上部法閣4之間的#壁石英管2構成。每個 法闌分別包含一固定外殼33與乜及可移動下部蓋罩补及上 部蓋軍4b，該等蓋罩可分別降低或升高以接取外殼i的内部 從而加載及卸載該裝置之熱區。外殼i可替代地由雙壁水冷 卻石英管構成或可由水冷卻不銹鋼外殼（未圖示）圍繞。枝 1之内部包含加熱器7 (文獻中亦稱為晶座或掛瑪），且盆由 低傳導性絕熱材料_繞，該材料諸如碳絕緣紙（咖⑽ _或與該處理及其加熱構件之溫度範圍相容之其它形離 或材料。加熱器7係軸對稱的且由與高溫相容之材料(諸如 未塗覆或塗覆之石墨、金屬碳化物或金屬氯化物或其組合 物)製成。加熱器可為圓柱形狀，然而，可軸向地改變加埶 元件之直徑以在某些區域中會聚或在其它區域分散從而在 加熱器7内及在晶體固持器12附近達成特定氣流型式或特 定空間溫度分佈。晶座7可由RF感應藉由盤管u或由電阻加 …來加熱至1900 C以上的溫度（且較佳在2〇〇〇。〇至鳩代範 圍内）以用於SiC晶體成具，十上此 日日版成長，或加熱至12〇〇t：以上的溫度（至 少11 〇〇°C且較佳在120(rc至220(rc之範圍内）以用於⑽晶 92736.doc -15- 1259214 體成長。使用機械或化學方法將晶種13安裝在實體附著至 賴軸上的晶種固持器12上，該機械軸具有至少一個中 工吕C 亥中空官道可由一光學高溫計或熱電偶（未圖 示)量測晶種固持器之溫度。為了在晶種表面而非晶座7之 表=24上獲得較佳結晶作用，晶種目持器維持在比表面μ 及室33之上部分低的溫度，藉此建立一溫度梯度。藉由穿 過受熱晶座7向晶種饋入含待成長材料之元素的汽相而實 現結晶處理。選擇待成長晶體之元素的量以使得受熱之蒸 A在到達、、a曰如端（此處稱為成長前端25a)時變得過飽和。 在成長之特疋狀況下，將晶座7加熱至在Η⑻至％⑽。c 之範圍的溫度，而晶種固持器維持在“⑻至以⑼它之範圍 的溫度，此視源材料饋入速率及其C/Si比率、晶種之多類 型及結晶定向而定。用於成長Sic結晶塊之較佳源材料由 SiHxCly氣體或液體（χ=〇至4，产〇至4)及諸如甲烷、乙烯或丙 烧之石反氫化合物組成。如美國專利第6,〇39,812號中所描 述，通過一®部管道22饋入含Si之氣體或液體。碳氫化合 物氣體可在相同管道22内饋入，或在圍繞該内部管道22並 由下。卩盖罩3b之水冷卻不銹鋼法闌21部分定界之同心環形 官道23内饋入。諸如氫、氦、氬或其混合物之載體氣體亦 被饋入至管道23中且經由一排出渠道14在成長前端25&之 下游排出。用於自其大體室溫儲存器饋入每一前驅物及氣 體之構件包括大流量控制器、閥門及CVD系統中慣有的其 匕組件。源材料可替代地由氣體前驅物與自儲存在晶座之 較低部分7a或單獨坩堝中之液體或固態源蒸發之元素的組 92736.doc -16- 1259214 合組成，諸如碳或碳化石夕粉末。 或者，在GaN成長之狀況下，可 及含氮氣體之有機金屬源用作源材料。甲_G) 積為：：：夕晶體碳化矽沿排氣渠道14之表面26及27沈 近戈：二額外的輸送構件，諸如在單晶體成長區附 ==於含Sl與。之氣體下的任何下游受熱部分中形 性的該4額外渠道來饋人具有化學㈣^之特 物岸：括: 發現:在批成長狀況下餘刻氣體混合 二人"幽族元素以中和含Si之蒸汽物質。钱刻 孔，“物較佳亦具有與含碳之蒸汽物質反應的特性，諸 如=已發現··提供所需結果之有效姓刻氣體混合物為諸 人，風(，2)、乳化虱(HC1)或氯氣㈤與氯化氯或氣氣的混 b物之氣體。含有諸如籲m ^ 、 齓（F)或碘⑴之_素與氫的氣體混合 勿亦月匕達到所要的姓刻效果。為了提供與本發明所實施之 ^日體扯與多晶體Sic之成長速率（〇 5至2麵化或更幻相 *山的钱刻比率’在排出氣體冷卻下降至低於單晶體成長前 端25a之溫度的6G(rc之溫度之前輸送㈣氣體之至少一部 刀為了使排耽通道14維持通暢，姓刻氣體混合物輸送構 # = & & ' “之㈣氣體及氫氣之量與比率應與含^與◦ 之，、、、/飞物貝的I、叉到凝結之表面溫度及排氣間隙Μ之傳 導性相匹配。 如圖3所示，藉由穿過機械軸16a及l6b之中空核心將受控 制之钕刻氣流輸送至在晶種固持器12中加工而成的内部輸 送腔内來實現一較佳㉟送方式。允許姓刻氣體混合物穿過 92736.doc 17 1259214 位於晶種13上方之渠道或微孔28逸出且與已穿過成長前端 25a之含Si與C的蒸汽物質相混合。 藉此將姓刻氣體混合物加熱至類似於晶種固持器溫度之 溫度，通常係2000至2400。(：，且因此蝕刻氣體混合物非常 有效地與含Si與C之蒸汽物質反應。應注意可在晶種固持器 12中使用複數個輸送組態以達成蝕刻氣體之平均分佈。例 如可沿晶種固持器12之外部表面26分佈直徑在〇1至若干 mm範圍内的複數個圓周形孔（circumferentiai h〇ie)。亦可使 用同孔隙率之環，只要該環係由對蝕刻氣體混合物呈化學 惰性之抗高溫材料（例如，當使用諸如6或〇2之純鹵素氣體 日丁則使用石墨）製成。第一輸送方式之一重要優勢在於：隨 著機械軸16被一拉伸單元（未圖示）以類似於Sic結晶塊15之 成長速率的速率向上平移，_氣流沿與晶體成長前端… 相關之曰曰種固持器總成之表面％輸送至一固定位置。甚至 田曰曰體成長至右干公分之長度且被向上拉伸對應高度時， 此亦允=表面27保持不會出現寄生固體沈積物。本發明之 :較：貫踐包括沿一預定軸向溫度分佈拉伸晶種固持器Η =使得，日日日表面25a之溫度隨晶體長度的增加而保持恒 二广者日日種固持心沿該溫度分佈拉伸，钱刻氣體流動 速率可隨時間推移線性變化以保持恒定的_ 輸送方式之另_樨埶产士人 乐一 k勢在於：可增加晶種固持器12與 熱器7a之間的溫罢， 、七加 的/皿差，而不會引起多晶體材料在 游的較高沈積速率。兴如二一 朴 平日日體15下 、羊牛例而έ，此可猎由以下方式而读+ . 降低在感應線圈之上、游園乾^ a 飞而達成- 游圈數11a中的RF功率，同時增加蝕刻 92736.doc 18 1259214 氣體混合物饋入至機械軸單元16之速率以平衡含&及c之 氣體的較高過飽和度。 用於實現本發明目的之蝕刻氣體混合物的第二輸送方式 包含將蝕刻氣體饋入至圍、繞晶種固持器12之加熱器的上部 部分7b中的渠道内。使用—外部流量控制器％來控制触刻 氣體饋入速率，且藉由-配件(fitting)將該蝕刻氣體饋入至 外殼4a中，該配件連接至在連接31處進入上部加熱器几之 石英管或管道以用於為内部管道32進料。内部管道Μ較佳 具有環形形狀且藉由複數個孔或藉由多孔媒介與排氣渠道 14相通。内部管道32較佳在先前技術裝置内之多晶體固體 沈積自然發生的區域内與渠道14相通。在寄生多晶體沈積 發生於表面26上之大面積上的狀況下，將第二渠道或若干 更多單獨渠道32安置於加熱器7b中以在需要保持無沈積物 之整個表面上輸送適當的蝕刻氣流。該第二蝕刻氣流饋入 系統實現了兩個㈣。第—目的是防止多晶體晶粒沿表面 26及27長晶及成長。然』，亦可將該_氣體流動速率調 整至比出於該單獨第-目的所需數值更高的數值以同樣钮 刻成長之單晶體15之側面25b。將該第二氣體混合物中鹵素 與氫的比率調整至用以製造成長之晶體15之側面的平滑鏡 狀蝕刻之數值。藉由改變蝕刻氣體流動速率來控制成長之 晶體的直徑。詳言之，錢刻流允許晶體以—放射狀比例 膨脹，該比例由蝕刻氣流對源氣體及載體氣體饋入至加熱 器7a中之的速率的戶斤€平衡與減器几之放射狀溫度梯度 來確定。可藉由增加蝕刻氣體流動速率來降低或甚至取消 92736.doc -19- 1259214 晶體之膨脹率以製造圓柱形的晶體。在該處理中，較佳旋 轉機械軸單元16以製造均衡的放射形狀。 該第二輸送方式之另一優勢在於：在本發明之溫度範圍 ，用包含諸如α之至少―㈣族元素的姓刻氣體與可 月匕:忍地被釋放於源氣體進料混合物中的若干金屬雜質形 成穩定的氯化物。詳言之，合 曰 之田允弄）置含ci氣體擴散至單 :體成“端…及25b時，單晶體15中殘餘的金屬雜質濃 :了減h達100之因子以低於可由當前技術水平之議 Ϊ測偵測到的數值。 用於實現本發明目的之㈣氣體混合物的第三輸送方式 包含沿加熱器7a之内壁與同心軸對稱形内部掛瑪&之間的 圓周形間隙饋入蚀刻氣體。如圖4所示，含sac之源蒸汽 流被限於成長區33中直至該蒸汽流掠過單晶體15之外: 25b且被排進渠道14中為止，而#刻氣流被限於環狀間隙^ 中直至該姓刻氣流遇到殘留在渠道14中的含SiAC之氣體 為止。在第士輸送方式中，蚀刻氣流之第三組態允許保持 表面26及27兩者不會出現有害的多晶體沈積物，且亦允許 其影響成長之單晶體的形狀。内部掛禍〜較佳具有圓柱形 外壁以製造大體為圓柱形的結晶塊15，而_沿姓刻氣流方 向？壬一方向分又之外壁可有利於凹形成長前端25a。 單獨地使用上述第一、第二或第三輸送方式中的任一個 或其組合使用皆屬於本發明之範脅。然而在可延長至數十 小時的整個處理持續時間内本發明最好藉由使用第一運輸 方式來實踐’而在該處理之不同階段則可較佳另外單獨或 92736.doc -20- 1259214 起使用第二與第三輸送方式。一典型實例在第一階段中 可係基於輸送方式1與2之晶體直徑膨脹階段，隨後係亦使 用應用較低蝕刻氣流之方式2或與輸送方式3組合使用方式 2之大致為圓柱形的成長。 應注意可使用該等特徵以達成用於各種排氣渠道14之組 恶的所要解決方法，諸如與單晶體成長方向相對的排氣方 向（如圖2所示），或垂直於成長方向的排氣裝置或任何在該 相對方向與垂直方向之間的中間角。 由本發明所教示之方法的一個重要實踐涉及選擇_素與 氫氣之流動速率及其各自之比例。儘管作者不希望受制於 任何理論，但是本方法中的教示可由熱力學考慮獲得。此 等屬於Si-C-H-Cl系統以下給定之内容，然而，可作出類似 發現以用於使用（例如）Ga善H_C14A1_N_H_C1系統之第m 族氯化物晶體成長之狀況。 在下文中，提供將氣添加至由輸入源氣體及載體氣體混 合物（例如SiH4，C3H8及HO確定之給定Si-C-H系統的特定狀 況。已自SiC CVD之先前技術中得知，在15〇〇_16〇〇。〇之溫 度範圍内將C1添加至Si-C-H系統之效應僅略微增強了 sic 之蝕刻速率。在先前技術熱壁CVD系統中之典型蝕刻條件 涉及低於0.03%之Cl/Η比率，且展示了蝕刻速率與增加的 HC1輸入之間的相關性比蝕刻速率與增加的出輸入進料速 率之間的相關性低[Zhang等人，Mate Sci· Foriims第 389-393卷（2002年出版）第239頁]。在先前技術中，對於本 發明之任何有用實踐而言蝕刻速率太低（在i 6〇〇〇c時小於 92736.doc -21 - 1259214 10 μιη/h)。此處將展示本發明應在高得多的ci/h下實踐以獲 得自0.1至大於1 mm/h之钱刻速率。 可藉由添加C1來將Sl_C_H中之過飽和度降低之定量量化 為溫度下降：當添加C1時’溫度可下降多少直至過飽和度 再次❹至原始值？初始Si_c_H組合物由輸入源混合物^ 界定藉由驅動該系統使其達到平衡來執行計算。藉由例 如氯石夕烧之形態來將料量之C1添加至該系統，此會降低 該系統之過飽和度。接著導致溫度降低Δτ，此量Μ增加 ㈣和度H接著驅動該系統達到新的氣相平衡且與初 始狀態相比較。接著可自諸如圖5及圖6中之輪庵繪圖中等 於！之過飽和度（SS)等值線獲得與給定则量對應的溫差八 許沿200它之溫度下降Δτ延遲任何實質的 1900°C時該下降可超過600°C。 τ。沿該等值線，SS(T，Si，c，H) = SS(T_A τ，以，c，h，卬 圖5展示在-系統在〇· i 2巴之減少壓力及〇 5之[ci]则比 率下操作之狀況的結果。詳言之，圖5指示在該狀況下已至 少部分地解決了渠道14阻塞之問題：固體批之成長大大減 ^且〜之錢亦完全停止。不幸的是，在氣相中以糾之含 量較大之高溫下，C1之效應則較小。在22〇〇。。下，〇可允 固相沈積，而在 使用[α_比率高於！之㈣氣體混合物可完全移除固 體沈積物之形成。如圖6所示，其中與圖5相同之塵力及初 始組合物❹L2之[C1]/間比率，甚至沿6m：之溫度下降 △τ’亦不可能生成Sl«Si之固相。然㈣於C過飽和度高 於1所以可月匕會沈積C之固相(諸如熱解石墨）。若該沈積物 92736.doc >22- 1259214 足夠大以致最終在20至40小時之時間内堵塞渠道14，則可 藉由實施本發明來移除該沈積物，即藉由將-額外h2流供 應至不再產生固體Sic沈積物之較冷區域中來完成此移除 步驟^可使用較早所描述的原理，在穿過機械軸單元16之 專用木道或牙過加熱器7之單獨渠道中饋人額外氫氣流。 本：：本土月成長之大型皁晶體可加以切片並研磨成用於 :-應用或可用於其它應用之薄晶圓。根據晶體所需之 用途’應瞭解可將晶體摻雜以達成低^型或&型電阻率中的 任一個，或將其製成非常純以達成高電阻率。諸如氮、銘 1 其它元素之摻雜劑較佳由受控制之氣流或有機金屬前驅 物引入成長室33中，此通常在用於半導體應用之薄層的训 c VD及第出族M〇c VD中進行。 :外，本發明亦可用於昇華或ρντ系統以使排出通道 ⑽usl°npath)不會出現沈積物，該等排出通道用於自，晶 則端移除自固體或液體源昇華之蒸汽的雜質或非 之組份中的任一個。 < ^ “在圖式及以上描述中已指示源氣流被向 體上與局部重力向量相對），但是以下均屬於本發明之範 :採將用=置於相對方向中，其”θ種位於該裝置底部； 5木7平方向’其令晶種固持器位於下方或上方任一 方。在其當前描述令’成長室33可保持在大致為大 250至_毫巴之範圍内的㈣下，然而為了該裝置之置 匕疋向’可能需要例如少於毫巴之低㈣達到所要 晶體成長速率。 92736.doc -23- 1259214 應注意熟習該項技術者將报容易地 内改變或修m峰、㈣及料灸 μ-定程度 之範疇及意圖。 ’而不背離本發明 【圖式簡單說明】 圖1說明一先前技術HTCVD成長裝置。 圖2說明另一先前技術111：¥(：：1)成長裝置。 圖3係根據本發明之裝置的橫截面。 圖4係根據本發明之經修改裝置的橫截面。 圖5展示[C1]/[H]比例為〇·5之Sic凝結物質卜⑽和加“ species)之過飽和比率（頂部圖）、碳凝結物質之過飽和比率 (中間圖）及石夕凝結物質之過飽和比率（底部圖）。 圖6展示[C1]/[H]比率為1.2之sic凝結物質之過飽和比 率、碳凝結物質之過飽和比率及矽凝結物質之過飽和比率。 【主要元件符號說明】 1 外殼 2 ..- 單壁石英管 3 下部法闌 3a 外殼 3b 下部蓋罩 4 上部法闌 4a 外殼 4b 上部蓋罩 7 加熱元件/加熱器/晶座 7b 上部加熱器 92736.doc -24- 下部加熱器 低傳導性絕熱材料 盤管 圈數 晶種固持器 晶種 排氣孔/排氣渠道 入口 /單晶體 排氣琿/機械軸單元 機械軸 機械軸 水冷卻不銹鋼法闌 内部管道 管道 表面 薄内圓筒 成長前端 側面 表面 表面 微孔 外部流量控制器 出口通道 内部管道 -25- 1259214 3 3 成長區/成長室 34 環狀間隙 92736.doc -26-And the self-vapor phase grows long crystals, both A version I, 曰力. This technique is generally referred to as high temperature 92736.doc 1259214 vapor phase deposition (HTCVD) and is different from the sealed ρντ configuration, except that it is used - an open type that provides precise control in source material supply and material exchange. Hot wall (〇penh〇t-wall) configuration. In detail, at least one of the growing material components is continuously supplied in a tempered manner, and is fed to the high temperature region by _::. In addition, an exhaust means is provided downstream of the crystallization zone to control the gas flow along the growing crystal surface and to discharge by-products produced by the crystallization process. Since this technique is conceptually similar to the CVD technique for growing a thick layer of M to 200 spleen, it can be referred to as vapor deposition (CVD). However, as in U.S. Patent No. 5, In order to achieve a cost-effective growth rate for the manufacture of large bulk crystals, HTCVD technology uses a source gas feed rate and a few orders of magnitude higher than normal CVD methods, as taught by No. 4,985 and No. 6,48,398. Baidu's temperature. / For example, in a device similar to the device in the first figure of U.S. Patent No. 5,7,4,985 (Fig., in the specific case of Sic, by seeding ( 13) heating to a temperature of 2250 C and feeding a 0.3 L/min decane and (u L/min ethylene gas mixture) diluted in the carrier gas through the inlet 15 to obtain a growth rate of 0.5 mm/h. After several hours of performing the method, it was observed in the experiment that sic also crystallized around the seed crystal substrate (13) in Fig. 1 and crystallized onto a holder (12) made of, for example, graphite and crystallized to the vent hole ( 14) on the exposed surface. On the surface directly adjacent to the seed crystal (13), S The ic crystal is a dense polycrystalline solid mainly comprising 6h&i5r. At the farther downstream of the venting hole 14, the sic crystal is a slightly less dense polycrystalline grain, which is usually needle-shaped and is more than 3c type. Dense polycrystalline deposition can occur at a rate of approximately 92736.doc 1259214 for a single crystal crystallization rate. Less dense polycrystalline deposits even grow faster, eventually blocking the gas exit channel within 2 to 4 hours. Once crystal The downstream oxygen-discharging channel is sufficiently blocked, that is, a pressure difference is rapidly formed between the source gas population 15 and the exhaust gas enthalpy. If the pressure difference is allowed to reach several mbar, the structural quality of the multi-type and single crystal is rapidly deteriorated. The source gas may also begin to flow along a channel having a higher conductivity than the blocked venting opening 14', for example by any porous insulating material such as 15 in Figure 1. Next, due to the reaction with bismuth, insulation The thermal properties of the material deteriorate rapidly, which forces the growth of the crucible. Or, when the exhaust passage 14 becomes blocked without allowing the source gas to find a channel of higher conductivity, due to polycrystalline Deposition of the crucible causes a non-rapid blockage of the gas introduction s. Under this condition, since no source gas can be supplied to the single crystal, the growth needs to be interrupted. Therefore, the parasitic deposition of the polycrystalline solid phase causes the system to be catastrophically out of control. , thereby forcing the growth process to be stopped before the fabrication of the #length crystal. An experimental solution to this problem has been proposed in PCT application WO 98/14644. In the case of SiC crystal growth, the application describes a garment. The process gas containing Si & c is separated from the main heating element 7 in Fig. 2 by a thin inner cylinder 25. A blanketing inen gas is forced to flow between the main heating element and the inner cylinder The inner cylinder terminates at a distance approximately corresponding to the growth front end of the single crystal. Downstream of the single crystal growth front end, the blanket gas is guided along the wall of the main heating cylinder, which is intended to prevent or substantially slow the deposition of the SiC polycrystal on the downstream inner wall and slow down the SiC polycrystal in the seed holder 13 grow up to keep the exit channel open. A similar solution is proposed in European Patent Application No. 787,822 A1. 92736.doc -10- 1259214 = method 'its + in _ and measured. The device operated between c has an inert covering gas flowing in parallel with the processing force of 1 L. = Solutions found in these documents or obtained from such documents have not solved the problems described above to the extent that ScC or other crystals having a length of several 匪 are sufficiently grown. An experimental demonstration using an inert cover such as helium or argon shows that there is still a rapid polycrystalline deposition in the downstream region of the growth front end of the single crystal. When helium is used as the covering gas, an even higher polycrystalline growth rate is easily obtained, and the use of argon merely pushes the deposition region downstream for a shorter period. This is explained by the additional flux of carbon carried by the blanket gas as it passes through the uncoated heating element made of graphite and by the different thermal conductivities of the gases considered by the two. Although there is any additional carbon supply in the Shixi exhaust mixture, the growth of polycrystalline sic downstream increases. A similar phenomenon was observed when using a heating element coated with Sic (10). To prevent this from happening, those skilled in the art will appreciate that a heating element coated with a metal carbide such as Ta C or N b C and V ¥ should be used as an improvement. Preferably, the exposed surfaces will also have a lower surface roughness to provide a less nucleated site for the polycrystalline SiC. However, it leads to 0.5 to! Under typical processing conditions for a single crystal growth rate of mm/h, it was observed that this design only resulted in the deposition of uncontrolled polycrystalline sic at a more downstream location. This small improvement in blocking time is not sufficient to continuously grow crystals of several cm length. In other prior art devices designed to grow SiC crystals, there is no mention of a solution to the parasitic deposition of the polycrystalline form of the material to be grown. In these devices, at least one component of the material to be grown is used as Gas feed 92736.doc -11 - 1259214 and the by-product of the process is discharged through the opening in the crucible. For example, European Patent No. 554,047 Β1 teaches the growth of Sic crystals by means of a device. 4 The device uses decane and propane as source gases, and the source gases react in the first reaction to form and subsequently evaporate in the lower pressure sublimation zone. Sic particles. The by-products of the crystallization process and the carrier gas are only described as being discharged through an outlet. A device is disclosed in U.S. Patent No. 5,985,024, the entire disclosure of which is incorporated herein by reference. In this apparatus, excess gas downstream of the growing SiC crystal block is also only described as being removed from the growth zone by an aisle or outlet channel. Since a reduced temperature distribution is required in or near the seed holder to promote the growth of SiC single crystals, it is believed that such passages will inevitably suffer from Sic polycrystals, pyry-lytic graphite or polycrystals. Catastrophic clogging caused by any of the Si deposits. A similar concept is described in U.S. Patent No. 6,48,398, the entire disclosure of which is incorporated herein by reference. The ruthenium fluoride is discharged downstream of the seed crystal holder, and the seed crystal holder is rotated and stretched as the single crystal grows. While the rotation of the seed holder results in a beneficial removal of polycrystalline deposits, such mechanical removal results in stress in the rotating mechanism or seed holder and causes the elements to begin to contact. This can result in mechanical failure of any of the above parts. A high temperature vapor phase deposition apparatus for fabricating SiC crystal blocks is discussed in U.S. Patent Application Serial No. 2002/0056411, wherein the pressure of the gas mixture in the growth zone is set to be higher than the pressure of the exhaust gas mixture to increase at 92,736. Doc -12- 1259214 Reasonable yield. This pressure difference can be achieved by designing the set so that the conductivity of the inlet is higher than the conductivity of the outlet. The low conduction (4) is placed downstream of the growth zone of the single crystal. At a constant temperature, the reduced pressure f of the exhaust mixture causes a decrease in the deposition rate of the parasitic polycrystalline material. This slows down any catastrophic blockage of the passage downstream of the exhaust zone. However, it is pointed out in the cited application that as the temperature decreases along the downstream passage, the deposit will again accumulate in a given area called the gas collector s (4). Preventing such deposition will allow the process to continue for a longer period of time and allow for the manufacture of longer crystals. Moreover, in the present application, the system must operate with reduced pressure at least in the downstream portion of the reduced conductivity region. It may be desirable to operate the device at substantially atmospheric pressure in both the growth zone and the outlet zone as this may benefit both the higher yield and lower cost of the overall system. It should be noted that the origin of the above problems is in the basic sense, even in the maximum amount of material transported at the front end of the single crystal growth. Since it is grown at a high temperature to promote a high growth rate and a high crystal quality, in order to prevent the surface from being graphitized, Si vapor of at least the same amount as the equilibrium Si pressure of the heated crystal surface is continuously discharged downstream of the growth tip. SUMMARY OF THE INVENTION The present invention provides a time for producing a crystal having a growth rate of several millimeters or preferably several centimeters at a high rate in a heated chamber (referred to as a crystal or a catastrophe) at a high temperature. A method and apparatus for growing a single crystal of any of Sic, a Group m nitride or an alloy thereof from a vapor phase. One of the objectives of the present invention is to slow or eliminate polycrystals and its formation 92736.doc •13-1259214. The formation of solid deposits downstream of the single crystal crystalline region avoids the entrance of the crystal lattice exhaust passage to the crystal. Partial or complete blockage caused by the gas mixture in the area. A related object of the present invention is to control the diameter of a growing single crystal and prevent the polycrystalline material from growing around it, thereby preventing structural defects from occurring in any of the high temperature growth phase or the subsequent cooling phase. A further object of the present invention is to reduce the concentration of undesirable metal impurities in the growth of a single crystal by removing the active metal element released from the private heated portion of the crystallization zone from the vapor phase. In order to prevent the formation of unwanted polycrystalline deposits on the surface near the single crystal growth region and on any surface downstream thereof, the present invention proposes to introduce a separate gas stream having the chemical properties of etching the deposits near the surfaces. Decreasing the local supersaturation of at least one component of the growing material. In the case where sic or GaN crystals are grown, it is preferred to use a gas stream containing at least one halogen element such as hydrogen chloride, chlorine or a mixture of hydrogen and chlorine or hydrogen chloride as an etchant. It will be readily apparent from the detailed description of the invention that other gases or gas mixtures containing halogens of the Br Br or I may also be used for similar purposes. The gas can also be distributed in this way to actively control the shape of the growing crystal. Other preferred features and advantages of the present invention will be apparent from the following description, description and claims. [Embodiment] FIG. 3 is a schematic diagram showing an improved device comprising a concept based on the concepts described in U.S. Patent Nos. 5,7,4,985, 6, 39,812 and 6,048,398. The device is described as a device 9 of the invention. The invention may have a principle construction similar to that mentioned above, but 92936.doc - 14-1259214 wherein the particular features and improvements described are different. For the growth of Sic or a single crystal of the m-th nitride. Some parts are schematically shown for the sake of simplicity, and those skilled in the art will understand that the device also includes, for example, a mass flow controller, a valve, a pump, Electronic controller, purifier, washing system and other components of the component, which in the CVD system is a conventional two-temperature chemical vapor deposition apparatus comprising a housing 1 which is, for example, securely mounted to the lower method 3 and the upper method The #4 quartz tube 2 is formed between the cabinets 4. Each of the magazines comprises a fixed outer casing 33 and a movable lower cover cover and an upper cover 4b, respectively, which can be lowered or raised respectively for picking up Shell i The interior thus loads and unloads the hot zone of the device. The outer casing i may alternatively be constructed of a double wall water cooled quartz tube or may be surrounded by a water cooled stainless steel casing (not shown). The interior of the branch 1 contains a heater 7 (also known in the literature) It is a crystal holder or hang-up), and the basin is made of a low-conductivity thermal insulation material such as carbon insulation paper (Cai (10) _ or other separation or material compatible with the temperature range of the treatment and its heating members. Heating The device 7 is axisymmetric and is made of a material that is compatible with high temperatures, such as uncoated or coated graphite, metal carbide or metal chloride or a combination thereof. The heater may be cylindrical in shape, however, The diameter of the twisting element is varied axially to converge in certain areas or to disperse in other areas to achieve a particular airflow pattern or specific spatial temperature distribution within the heater 7 and near the crystal holder 12. The crystal holder 7 can be RF induced It is heated to a temperature above 1900 C (and preferably in the range of 2 〇〇〇. 〇 to the range of 鸠) by the coil u or by the resistance addition... for the SiC crystal forming, and the Japanese version is growing on this day. , or heated to 12〇〇t: The temperature above (at least 11 〇〇 ° C and preferably at 120 (rc to 220 (in the range of rc) for the growth of (10) crystal 92736.doc -15-1259214. Use the mechanical or chemical method to install the seed crystal 13 The substrate is attached to the seed holder 12 on the razor axis, and the mechanical shaft has at least one zhonglulu Chai hollow channel. The temperature of the seed holder can be measured by an optical pyrometer or a thermocouple (not shown). In order to obtain a better crystallization effect on the surface of the seed crystal and on the surface of the amorphous seat 7 = 24, the seed crystal holder maintains a temperature lower than the surface μ and the portion above the chamber 33, thereby establishing a temperature gradient. The crystallization treatment is carried out by feeding the vapor phase of the element containing the material to be grown to the seed crystal through the heated crystal seat 7. The amount of the element of the crystal to be grown is selected such that the heated vapor A becomes supersaturated when it reaches, for example, the end (herein referred to as the growth front end 25a). In the case of growth, the crystal holder 7 is heated to Η(8) to %(10). The temperature in the range of c, while the seed holder is maintained at "(8) to (9) its temperature range, depending on the source material feed rate and its C/Si ratio, the type of seed crystal and the crystal orientation. Preferred source materials for growing Sic crystal blocks are composed of SiHxCly gas or liquid (χ=〇 to 4, calving to 4) and anti-hydrogen compounds such as methane, ethylene or propylene oxide. For example, U.S. Patent No. 6, 〇39,812 As described in the section, a gas or liquid containing Si is fed through a section pipe 22. The hydrocarbon gas may be fed into the same pipe 22, or may be surrounded by the inner pipe 22 and the water of the cover 3b. The cooling stainless steel method 21 is partially fed into the concentric annular tunnel 23. A carrier gas such as hydrogen, helium, argon or a mixture thereof is also fed into the conduit 23 and passed through a discharge channel 14 at the growth front end 25 & Downstream discharge. The components used to feed each precursor and gas from its bulk room storage include large flow controllers, valves, and their conventional components in CVD systems. The source material may alternatively be a gas precursor and Self-storing in the lower part of the crystal seat 7a or single a combination of elements of liquid or solid source evaporation in the crucible, 92736.doc -16-1259214, such as carbon or carbon carbide powder. Alternatively, in the case of GaN growth, an organic metal source capable of containing a nitrogen gas is used as Source material. A_G) Product::: 晶体 Crystal carbide 矽 along the surface of the exhaust channel 14 26 and 27 sinking near: two additional transport members, such as in the single crystal growth zone attached == in the containing S1 and The 4 additional channels of shape in any downstream heated part of the gas are fed to have a chemical (4) ^ special object: including: found: in the batch growth condition, the remaining gas is mixed with two people " A vaporous substance containing Si. The money is engraved. "The material preferably also has the property of reacting with a carbonaceous vaporous substance, such as = already found. · Providing the desired result of the effective surname of the gas mixture for the person, wind (, 2 ), a gas of emulsified hydrazine (HC1) or chlorine (5) mixed with chlorine chloride or gas. Mixing a gas containing hydrogen such as 吁m ^ , 齓 (F) or iodine (1) with hydrogen to achieve the desired effect of the last name. In order to provide the growth rate of the body and the polycrystalline Sic (the 〇5 to 2 facet or the illusion of the mountain), the exhaust gas cooling is lowered to be lower than the single crystal growth front end 25a. At a temperature of 6G (at the temperature of rc, at least one of the knives of the gas is transported to keep the venting passage 14 unobstructed, the surname of the gas mixture transport structure # = && 'the (four) gas and hydrogen amount and ratio should be The surface temperature of the I, the fork, and the surface of the condensate containing the y, y, and y, are matched with the conductivity of the venting gap 。. As shown in Fig. 3, by hollowing through the mechanical shafts 16a and 16b The core delivers a controlled entrained gas stream to an internal delivery chamber machined in the seed holder 12 to achieve a preferred 35-feed mode. The surname gas mixture is allowed to pass through 92736.doc 17 1259214 in seed crystal 13 The upper channel or micropore 28 escapes and mixes with the vaporous material containing Si and C that has passed through the growing front end 25a. Thereby the surging gas mixture is heated to a temperature similar to the temperature of the seed holder, typically 2000 To 2400. (:, and therefore the etching gas mixture The material reacts very efficiently with the vaporaceous material containing Si and C. It should be noted that a plurality of transport configurations can be used in the seed crystal holder 12 to achieve an even distribution of the etching gas. For example, along the outer surface 26 of the seed crystal holder 12. A plurality of circumferential holes having a distribution diameter in the range of 1 to several mm. It is also possible to use a ring of the same porosity as long as the ring is made of a high temperature resistant material which is chemically inert to the etching gas mixture (for example It is made of graphite when using a pure halogen gas such as 6 or 〇2. One of the important advantages of the first conveying method is that the mechanical shaft 16 is similar to Sic by a stretching unit (not shown). The rate of growth rate of the crystal block 15 is shifted upwards, and the _ airflow is transported to a fixed position along the surface % of the retainer assembly associated with the crystal growth front end. Even the field body grows to the length of the right stem centimeter and When the corresponding height is stretched upwards, this also allows the surface 27 to remain free of parasitic solid deposits. The present invention: more than: stretching the seed crystal holder along a predetermined axial temperature distribution Η It is found that the temperature of the surface 25a of the day and the day increases with the increase of the crystal length, and the day-to-day holding core is stretched along the temperature distribution, and the gas flow rate can be linearly changed with time to maintain a constant state. The other _ 樨埶 樨埶 人 乐 乐 乐 乐 ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ ̄ High deposition rate. Xingru is a two-day Puping day, 15 days, and the sheep and cattle are squatting. This can be read by the following method. + Lowering on the induction coil, the garden is dry and a fly to reach - the number of swims 11a The RF power in the process is simultaneously increased by the rate at which the etch 92736.doc 18 1259214 gas mixture is fed to the mechanical shaft unit 16 to balance the higher supersaturation of the gases containing & and c. The second mode of transport of the etching gas mixture for achieving the objects of the present invention includes feeding an etching gas into the channels surrounding the upper portion 7b of the heater of the seed crystal holder 12. The external flow controller % is used to control the etch gas feed rate, and the etch gas is fed into the outer casing 4a by fitting - the fitting is connected to the quartz entering the upper heater at the connection 31 A tube or pipe is used to feed the internal pipe 32. The inner conduit Μ preferably has a toroidal shape and communicates with the exhaust passage 14 by a plurality of holes or by a porous medium. The inner conduit 32 preferably communicates with the channel 14 in a region where the deposition of polycrystalline solids in the prior art device occurs naturally. In the case where parasitic polycrystalline deposition occurs over a large area on the surface 26, a second channel or a plurality of more individual channels 32 are placed in the heater 7b to deliver a suitable etch on the entire surface where it is desired to remain free of deposits. airflow. The second etch gas feed system implements two (four). The first purpose is to prevent polycrystalline grains from growing and growing along surfaces 26 and 27. However, the gas flow rate can also be adjusted to a side 25b of the single crystal 15 which is grown by the same value as the value required for the individual first purpose. The ratio of halogen to hydrogen in the second gas mixture is adjusted to the value of the smooth mirror etching used to fabricate the side of the growing crystal 15. The diameter of the growing crystal is controlled by changing the flow rate of the etching gas. In detail, the engraving of the money allows the crystal to expand in a radial proportion, which is the ratio of the rate at which the source gas and the carrier gas are fed into the heater 7a by the etching gas stream. Gradient to determine. The expansion ratio of the crystal can be reduced or even eliminated by increasing the flow rate of the etching gas to produce a cylindrical crystal. In this process, the mechanical shaft unit 16 is preferably rotated to produce a balanced radial shape. Another advantage of this second mode of transport is that in the temperature range of the present invention, a gas containing a surname containing at least a group of elements such as alpha and a ruthenium can be released into the source gas feed mixture. Metal impurities form a stable chloride. In detail, the combination of the ci gas and the ci gas diffusion to the single: body "end ... and 25b, the residual metal impurities in the single crystal 15 is concentrated: the factor of minus h up to 100 is lower than the current technology The level of the detected value is measured. The third mode of transport of the (IV) gas mixture for achieving the object of the present invention comprises a circumferential gap feed between the inner wall of the heater 7a and the concentric axis. An etching gas is introduced. As shown in FIG. 4, the source sac-containing vapor stream is confined to the growth zone 33 until the vapor stream passes over the single crystal 15: 25b and is discharged into the channel 14, and the #刻流流 is limited to the ring. In the gap ^ until the surname of the gas stream encounters the SiAC-containing gas remaining in the channel 14. In the taxi mode, the third configuration of the etch gas stream allows the surfaces 26 and 27 to remain unharmed. Polycrystalline deposits, and also allow them to influence the shape of the growing single crystal. Internally collapsed ~ preferably has a cylindrical outer wall to make a generally cylindrical crystalline block 15, and _ along the direction of the gas flow in the last name The outer wall can facilitate concave formation Long front end 25a. The use of any one of the first, second or third transport modes described above, or a combination thereof, is within the scope of the present invention. However, the present invention can be extended over the entire processing duration of up to tens of hours. Preferably, by using the first mode of transport, the second and third modes of transport are preferably used separately at different stages of the process or 92736.doc -20-1259214. A typical example is in the first stage. The medium diameter can be based on the crystal diameter expansion stage of the transport modes 1 and 2, and then the substantially cylindrical growth using the lower etching gas flow mode 2 or the transport mode 3 is also used. It should be noted that these can be used. Features to achieve a desired solution for the various components of the various exhaust channels 14, such as the direction of the exhaust opposite the growth direction of the single crystal (as shown in Figure 2), or the exhaust device perpendicular to the growth direction or any of the relative An intermediate angle between the direction and the vertical direction. An important practice of the method taught by the present invention involves selecting the flow rate of _ and hydrogen and their respective ratios. It is not intended to be subject to any theory, but the teachings in the method can be obtained by thermodynamic considerations. These are the contents given below for the Si-CH-Cl system, however, similar findings can be made for use with, for example, the Ga Shan H_C14A1_N_H_C1 system. The condition of the growth of the m-th chloride crystal. In the following, a specific condition for adding a gas to a given Si-CH system determined by the input source gas and the carrier gas mixture (for example, SiH4, C3H8 and HO) is provided. It has been known in the prior art that the effect of adding C1 to the Si-CH system over a temperature range of 15 〇〇 16 〇〇 仅 only slightly enhances the etch rate of sic. Typical in prior art hot wall CVD systems The etching conditions involve a Cl/Η ratio of less than 0.03%, and demonstrates that the correlation between the etch rate and the increased HC1 input is lower than the correlation between the etch rate and the increased input feed rate [Zhang et al. Mate Sci·Foriims, vol. 389-393 (published in 2002), p. 239]. In the prior art, the etch rate was too low for any useful practice of the invention (less than 92736.doc -21 - 1259214 10 μηη/h at i 6〇〇〇c). It will be shown herein that the invention should be practiced at much higher ci/h to obtain a rate of money from 0.1 to greater than 1 mm/h. The quantitative reduction of the supersaturation in Sl_C_H can be quantified by adding C1 to a temperature drop: How much can the temperature drop when C1 is added until the supersaturation is again reached to the original value? The initial Si_c_H composition is defined by the input source mixture ^ by driving the system to equilibrium. The amount of C1 is added to the system by, for example, the form of chlorite, which reduces the supersaturation of the system. This then results in a temperature decrease Δτ, which increases (4) and the degree H then drives the system to reach a new gas phase equilibrium and is compared to the initial state. It can then be drawn from a rim such as in Figures 5 and 6! The supersaturation (SS) contour obtains a temperature difference corresponding to a given amount. The temperature drop Δτ of 200 is delayed by any substantial 1900 ° C. The drop may exceed 600 ° C. τ. Along the contour, SS(T, Si, c, H) = SS(T_A τ, to, c, h, 卬 Figure 5 shows the decreasing pressure of the system at 〇·i 2 bar and 〇5[ci The result of the situation of the operation under the ratio. In detail, Figure 5 indicates that the problem of blockage of the channel 14 has been at least partially solved under this condition: the growth of the solid batch is greatly reduced and the money of ~ is also completely stopped. Unfortunately Yes, in the gas phase, the effect of C1 is small at high temperatures, and at 22 〇〇, 〇 can allow solid phase deposition, while using [α_ ratio higher than ! (4) The gas mixture can completely remove the formation of solid deposits. As shown in Fig. 6, the same dust force as in Fig. 5 and the [C1]/interval ratio of the initial composition ❹L2, even decrease by Δτ' along the temperature of 6m: It is impossible to generate a solid phase of Sl «Si. However, (4) a solid phase of C (such as pyrolytic graphite) may be deposited on the Moon after the C supersaturation is higher than 1. If the deposit is 92736.doc >22-1259214 is large enough So that the channel 14 is eventually blocked within 20 to 40 hours, the deposit can be removed by practicing the invention by supplying an additional h2 stream to This removal step is no longer produced in the colder regions of the solid Sic deposits. It can be fed in a separate channel through the dedicated wood or tooth over heater 7 of the mechanical shaft unit 16 using the principles described earlier. Extra hydrogen flow for humans. Ben:: Large-scale soap crystals grown in the local month can be sliced and ground into thin wafers for: - application or for other applications. According to the intended use of the crystal 'it should be understood that the crystal can be doped To achieve either a low or & type resistivity, or to make it very pure to achieve high resistivity. Dopants such as nitrogen, other elements of the first element are preferably controlled by a gas stream or an organometallic The precursor is introduced into the growth chamber 33, which is typically performed in a thin layer of V VD for semiconductor applications and a population of M 〇c VD. In addition, the present invention can also be applied to a sublimation or ρντ system for the discharge channel (10) usl °npath) No deposits are present which are used to remove any of the impurities or non-components of the vapor sublimated from the solid or liquid source. < ^ "In the description of the drawings and the above description, the source gas flow has been indicated to be physically opposite to the local gravity vector), but the following are all within the scope of the invention: the use of = is placed in the opposite direction, the "θ species are located The bottom of the device; 5 wood 7 flat direction 'it makes the seed holder either below or above. In its current description, 'the growth chamber 33 can be maintained at (b) in the range of approximately 250 to _mbar, but for the device, it may be necessary to achieve, for example, less than mbar (four) to achieve the desired crystal. Growth rate. 92736.doc -23- 1259214 It should be noted that those skilled in the art will report the scope and intent of easily changing or repairing m peaks, (4) and moxibustion. Without departing from the invention [Schematic Description of the Drawings] Figure 1 illustrates a prior art HTCVD growth apparatus. Figure 2 illustrates another prior art 111: ¥(::1) growth device. Figure 3 is a cross section of a device according to the invention. Figure 4 is a cross section of a modified device in accordance with the present invention. Figure 5 shows the supersaturation ratio (top graph) of the Sic condensate (10) and the " species" with a ratio of [C1]/[H] of 〇·5, the supersaturation ratio of the carbon condensate (middle), and the condensate of the stone Supersaturation ratio (bottom graph) Figure 6 shows the supersaturation ratio of the sic condensate with a ratio of [C1]/[H] of 1.2, the supersaturation ratio of the carbon condensate, and the supersaturation ratio of the condensed material. [Main component symbol description] 1 2 ..- Single-walled quartz tube 3 Lower method 3a Housing 3b Lower cover 4 Upper method 4a Housing 4b Upper cover 7 Heating element / heater / crystal holder 7b Upper heater 92736.doc -24- Lower heater Low Conductivity Insulation Material Coil Circle Number Crystal Holder Seed Exhaust Hole / Exhaust Channel Inlet / Single Crystal Exhaust / Mechanical Shaft Unit Mechanical Shaft Mechanical Shaft Water Cooled Stainless Steel Method Internal Pipeline Surface Thin Inner Cylinder Growth Front side surface surface micro-hole external flow controller outlet channel internal pipe -25- 1259214 3 3 growth zone / growth chamber 34 annular gap 92736.doc -26-