201025454 六、發明說明： 【發明所屬之技術領域1 本發明係關於一種藉由RTA埶虚# …、惠理於主體部形成空 洞’賦予吸氣（吸雜（gettering))能力的矽晶 【先前技術】 。 加工以切克勞斯基法（CZ法）而被拉引成長的單晶 石夕，而被製作出來的矽晶圓，含有大量的氧不純物此氧 ❹不純物係成為使差排、缺陷等發生的氧析出物（Busier。 defect; BMD)。氧析出物位於元件要被形成的表面的情況 時，成為漏電流增大、氧化膜耐壓降低等的原因，對於半 導體元件的特性造成重大的影響β 因此，先前，採用一種方法（參照專利文獻丨），對於 砍晶圓表面’於預定的氣氛氣體中，以125〇。〇以上的高溫 施行短時間的急速加熱和急冷的熱處理（Rapid thermal annealing ; RTA) ’於内部形成高濃度的熱平衡的原子空洞 (Vacancy ’以下僅稱為空洞），藉由急冷而凍結，且以之 後的熱處理’於表面使空洞向外方擴散，藉此來均勻地形 成DZ層（Denuded zone或無缺陷層）。然後，此DZ層形 成後’採用一種製程，利用施行較上述熱處理溫度低溫的 熱處理’形成並安定化氧析出核，而形成具有吸氣效果的 BMD(主醴微缺陷）層來作為主體部的缺陷層。如此所得到 的矽晶圓，係如第3圖般，表層具有DZ層31，主體部具 有BMD層32。 3 201025454 又，作為其他方法，亦有先在氧氣氛下進行熱處理， 接著，於非氧化性氣氛下進行熱處理，藉此，於矽晶圓表 面進行DZ層的形成，且於主體部進行BMD層的形成。另 外，先前，在用以形成空洞的熱處理中，主要使用氮（N2) 來作為氣氛氣體。亦即，藉由在高溫下氮被分解，氮化膜 (SixNy )被形成於矽晶圓表面而注入空洞。 但是，如上述般的矽晶圓的熱處理技術，殘留有以下 ❹的課題。先前，當施行用以形成空洞的熱處理之際，熱處 理係於以氮為主的氣氛氣體中被進行，此時，為了獲得充 分量的空洞，必須在1250。(；以上的溫度進行1〇秒以上的 熱處理。 因此，在矽晶圓中，會因為高溫的熱處理，從與承受 體（susceptor)或支持銷等接觸的部分發生滑移，而有成為破 裂等的原因的不良。 對此，在專利文獻2中提出一種技術，以包含較可分 ❹解氮的溫度低的分解溫度的氮化氣體（ΝΑ等）的氣氛氣 體，作為氣氛氣體，來施行熱處理製程，對矽晶圓進行熱 處理，而在内部新形成空洞。藉此，即便是較氮氣的情況 低的熱處理溫度或短的熱處理時間，氮化氣體亦被分將 矽晶圓表面氮化而注入空洞於内部，可抑制熱處理時的滑 移發生，且以之後的熱處理，使表面具有充分的Dz層， 主體部具有適度高的BMD密度，而可獲得一種高品質的晶 圓。 但是，必須有用以供給有害的ΝΑ的設備，而有設備 4 201025454 成本增加這樣的問題。 [先前技術文獻] (專利文獻） 專利文獻1 :日本專利國際公開手冊W098/38675號 專利文獻2 :曰本專利公開公報特開2003 — 3 1 582號 【發明内容】 _ 對此，本發明係有鑑於如此的問題點而開發出來，其 目的係提供一種可製造高品質的矽晶圓的方法，使對矽晶 圓施行的RTA熱處理低溫化或短時間化，抑制石夕晶圓發生 滑移’且不使用NH3，便可將空洞注入矽晶圓内部。 為了達成上述目的’本發明係提供一種矽晶圓的製造 方法，至少具有在氣氛氣體中對矽晶圓施行rTA熱處理的 製程，其特徵在於··使用一種在氮氣中混入5ppm以上 25 0ppm以下的濃度的水分而成的氣體，作為前述氣氛氣 φ 體，來施行RTA熱處理。 如此’藉由在使微量的水分混入氮氣中而成的氣氛中 進行RTA熱處理，即便是較低溫的熱處理，亦可於妙晶圓 表面形成氮氧化膜。因此，利用氮與矽原子反應，可有效 率地將空洞注入矽晶圓内部。藉此’即便氣氛氣體中不使 用NH3等的有毒氣體，亦可利用較低溫的熱處理，將充分 量的空洞注入矽晶圓内部。 因此，利用進行本發明的RTA熱處理，即可低成本地 201025454 製造出一種無滑移的高品質晶圓’藉由之後的熱處理’在 表面具有DZ層，在主體部具有充分的密度的BMD ° 此時，較佳是使用一種在氮氣中混入l〇PPm以上 1 5 Oppm以下的濃度的水分而成的氣體，來作為前述氣氛氣 體。 如此，因使lOppm以上I50ppm以下的濃度的水分混 入氮氣中而成的氣體，來作為氣氛氣體，可將更多的空洞 注入晶圓内部，即便是低溫熱處理，亦可獲得與利用NH3 ❹的氣氛來進行RTA熱處理的情況同等以上的bmD密度。 此時’較佳是藉由控制氮氣的露點來調整混入氮氣中 的水分濃度，作成前述氣氛氣體。 如此’利用控制氮氣的露點，可更容易地進行混入的 水分濃度的調整。 此時，較佳是藉由將氮氣的露點控制在_ 6〇〇c以上— 38。(：以下，使10ppm以上15〇ppm以下的濃度的水分混入 φ 氮氣中’作成前述氣氛氣體。 利用將氛氣的露點控制在上述範圍，可更容易地將水 分浪度調整在1()ppm以上15Qppm以下這樣的較佳範圍内。 此時，要被施行前述RTA熱處理的石夕晶園的相期氧滚 度，較佳是設為9ΡΡπ^Χ± l4ppma以下。 即便疋如此的低氡濃度的m若依據本發明的 RTA熱處理，即便低溫亦可注人充分的空洞量，由於可作 成一：無滑移、高ΒΜ〇密度”晶圓，因此無析出過多， 所以是較佳的。 夕 6 201025454 此時’可使Μ層成長於被施行前述rta熱處理後的 妙晶圓的表面。 若為被施行本發明的RTA熱處理後的梦晶圓則因主 體部具有充分量的空洞，表面的結晶性亦良好即便於以 尚溫進行磊晶成長的矽晶圓的製造，，亦可引起良好的氧 析出，具有高BMD密度，且可得到良好的磊晶層所以是 較佳的。 若依據本發明，不使用ΝΑ等的有毒氣體，便可低成 本地製造出一種無滑移、具有Dz層與高BMd密度的矽晶 圓。 【實施方式】 先前，使用NH3等有毒氣體、或進行高溫的熱處理， 來將空洞注入發晶圓，但有滑移的發生、成本方面的問題 等。 ❹ 對此，本發明人，對於即便是較低溫的熱處理，不使 用NH3等亦可注入空洞的熱處理方法，進行深入研究後的 結果，發現：使用一種將微量的水分混入氮氣中而成的氣 體來作為RTA熱處理時的氣氛氣體，則即便是較低溫，空 洞亦可被注入矽晶圓内部。 再者’本發明人’為了調查適當的水量，對於藉由各 式各樣的水分滚度的氮氣氣氛與包含NH3的氣氛，進行 RTA熱處理（1175°C / 30秒）後的矽晶圓，施行用以形成 7 201025454 氧析出物也就是BMD的二階段熱處理（8〇〇。(：/四小時、 l〇〇〇°C /十六小時）’然候調查其BMD密度，藉此而得到 如第1圖般的結果。第1圖係表示混入作為RTA熱處理的 氣氛氣體的氮氣中的水分濃度與BMD密度的關係的圓表。 由第1圖可知，因RTA熱處理溫度較低溫，在純粹的 氮氣（N2 )中，氧析出不充分’但利用將5pprn ( N2 + h20 (5ppm))以上的水分混入氮氣中，則產生良好的氧析出； 再者，得知：在l〇ppm〜 15ppm的範圍内，相較於在相同 ❹的熱處理條件下’於包含NH3的氣氛氣體（NH3/Ar)中 進行RTA熱處理後的矽晶園，其BMD密度更高。 又’若水分濃度超過250ppm，則BMD密度大幅地降 低’此係被認為是因為在RTA熱處理中，由於水分而形成 氧化膜，晶格間被注入石夕（Si) ’空洞量減少，氧析出會被抑 制的緣故。 由以上發現，使用一種在氮氣中混入5ppm以上 ❹ 250ppm以下的濃度的水分’較佳係混入1 〇ppm以上15〇ppm 以下的濃度的水分而成的氣體，來作為RTA熱處理的氣氛 氣體，即便是較低溫’亦可注入充分的空洞，可製造出一 種具有高密度的BMD層之矽晶圓，而完成本發明。 以下，一邊參照圖式，一邊具體地說明本發明的實施 形態，但本發明不限定於這些實施形態。 首先，在第2圖中表示可於本發明使用的RTa用的熱 處理爐的一例。在本發明中，由於不必使用NH3等的有毒 8 201025454 氣體巾可使用實質上與先前相同的設備來作為熱處理爐。 熱處理爐2G ’係具備：用以塞住石夕晶圓w的搬入口的 用以供給氣氛氣體的氣體供給口 22、用以排出氣氛 氣體的氣體排出口 24、田丨、丨 用以載置梦晶圓的承受體23、以及 加熱碎晶圓W的燈21» 在如此的熱處理爐20内載置矽晶圓w，從氣體供給口 22，一邊流通氣氛氣體，一邊進行rta熱處理。 本發明中，使用一種在氮氣中混入5ppm以上25〇ppm 以下的濃度的水分而成的氣體，來作為使用如上述般的熱 處理爐的RTA熱處理中的氣氛氣體。 通常的純粹的氮氣，其水分係被定於至少約2ppm以 下，先前因被認為不含水分的氣氛會引起空洞注入，因此 該純粹的氣氣的水分濃_度被調整成更小β 相對於此，在本發明中，於故意地使本發明的範圍内 的微量濃度的水分混入氣氣中而成的氣氛中，進行rta熱 瘳處理，藉此’即便是較低溫的熱處理，亦可於矽晶圓表面 形成氮氧化膜。藉此’利用氮與矽原子反應，可有效率地 將空洞注入梦晶圓内部。因此’即便氣氛氣體中不使用nh3 等的有毒氣體’亦可利用較低溫的熱處理，於矽晶圓内部， 注入充分量的空洞。 如以上般地’藉由進行本發明的RTA熱處理，即可低 成本地製造出一種在内部具有充分的BMD密度的高品質 且無滑移的矽晶圓。 又，較佳是將混入氮氣中的水分濃度設為1 〇ppm以上 9 201025454 150ppm 以下》 利用一種混入此濃度範圍内的水分而成的氣體來作為 氣氛氣體，藉此可注入較多的空洞，即便是低溫熱處理， 亦可得到高於使用NH3的氣氛來進行RTA熱處理後的矽晶 圓的BMD密度，因此，可製造出一種更高品質的矽晶圓。 此時，較佳是藉由控制氮氣的露點，來調整混入氮氣 中的水分濃度；較佳是藉由將氮氣的露點控制於一60°C以 上一38C以下，使1 〇ppm以上1 50ppm以下的漠度的水分 ®混入氣氣中（半導體產業中被用的氮氣，其露點被設在一 70°C以下）。 在本發明的RTA熱處理中所使用的氮氣中的水分濃 度，由於係非常微量，所以若依據控制該露點的方法，即 可令易地進行水分濃度的調整再者，在上述般的較佳的 水分濃度範圍内的調整，亦變得更容易。 ® W T ’ &第1表中表示氮氣的露點與水分濃度的關係。 10 201025454 [第1表]201025454 VI. Description of the Invention: [Technical Field 1 of the Invention] The present invention relates to a crystal having the ability to impart a gettering (gettering) by forming an empty hole in the body portion by RTA. 】. The single crystal stone that has been drawn and grown by the Czochralski method (CZ method) is processed, and the silicon wafer produced by the method contains a large amount of oxygen impurities, which causes the difference in defects, defects, and the like. Oxygen precipitate (Busier. defect; BMD). When the oxygen precipitate is located on the surface on which the element is to be formed, it causes a large leakage current, a decrease in the withstand voltage of the oxide film, and the like, and has a significant influence on the characteristics of the semiconductor element. Therefore, a method has been used previously (refer to the patent literature).丨), for chopping the wafer surface 'in a predetermined atmosphere gas, to 125 〇. The above-mentioned high temperature is subjected to a short-time rapid heating and rapid thermal annealing (RTA) to form a high-concentration thermal equilibrium atomic cavity (Vacancy ', simply referred to as a cavity), which is frozen by quenching and is The subsequent heat treatment 'disperses the cavity outward to the surface, thereby uniformly forming a DZ layer (Denuded zone or defect-free layer). Then, after the formation of the DZ layer, a process of forming and solidifying the oxygen evolution nucleus by performing a heat treatment at a lower temperature than the above heat treatment temperature is used to form a BMD (main 醴 micro defect) layer having a gettering effect as a main body portion. Defective layer. The tantalum wafer thus obtained has a DZ layer 31 in the surface layer and a BMD layer 32 in the main portion as in Fig. 3. 3 201025454 Further, as another method, heat treatment is performed in an oxygen atmosphere, and then heat treatment is performed in a non-oxidizing atmosphere, whereby a DZ layer is formed on the surface of the tantalum wafer, and a BMD layer is formed on the main body portion. Formation. Further, previously, in the heat treatment for forming voids, nitrogen (N2) was mainly used as the atmosphere gas. That is, by dissolving nitrogen at a high temperature, a nitride film (SixNy) is formed on the surface of the germanium wafer to inject a void. However, the heat treatment technique of the tantalum wafer as described above remains the subject of the following problems. Previously, when a heat treatment for forming a void was performed, the heat treatment was carried out in a nitrogen-based atmosphere gas, and at this time, in order to obtain a void of the charge, it was necessary to be 1250. (The above temperature is heat-treated for 1 sec. or more. Therefore, in the ruthenium wafer, the portion that comes into contact with the susceptor or the support pin may be slipped due to the high-temperature heat treatment, and may become cracked or the like. In view of this, in Patent Document 2, a technique is proposed in which an atmosphere gas containing a nitriding gas (ΝΑ, etc.) having a decomposition temperature lower than the temperature at which nitrogen is decomposed is used as an atmosphere gas to perform heat treatment. The process heat-treats the wafer and creates a new void inside. Thus, even if the heat treatment temperature is lower than the case of nitrogen or the heat treatment time is short, the nitriding gas is nitrided and nitrided on the surface of the wafer. The void is inside, and the occurrence of slip during heat treatment can be suppressed, and the surface is provided with a sufficient Dz layer by the subsequent heat treatment, and the body portion has a moderately high BMD density, so that a high-quality wafer can be obtained. In order to supply a device that is harmful to cockroaches, there is a problem that the cost of the device 4 201025454 increases. [Prior Art Document] (Patent Document) Patent Document 1: Japan Patent Publication No. WO 098/38675, the disclosure of which is hereby incorporated herein by reference in its entirety in its entire entire entire entire entire entire entire entire entire content A method for manufacturing high-quality germanium wafers, which can lower the temperature or short-time of the RTA heat treatment performed on the germanium wafer, inhibit the slippage of the Shihua wafer, and inject the void into the wafer without using NH3. In order to achieve the above object, the present invention provides a method for manufacturing a tantalum wafer, which has at least a process for performing rTA heat treatment on a tantalum wafer in an atmosphere gas, characterized in that a type of nitrogen gas is mixed with 5 ppm or more and 25 ppm. The gas of the following concentration of water is subjected to RTA heat treatment as the atmosphere gas φ. Thus, by performing RTA heat treatment in an atmosphere in which a small amount of water is mixed into nitrogen gas, even at a relatively low temperature heat treatment, Nitrogen oxide film can also be formed on the surface of the wafer. Therefore, by reacting nitrogen with germanium atoms, voids can be efficiently injected into the interior of the germanium wafer. A toxic gas such as NH3 is not used in the atmosphere gas, and a sufficient amount of voids can be injected into the inside of the wafer by a lower temperature heat treatment. Therefore, by performing the RTA heat treatment of the present invention, a low cost can be produced at 201025454. The slipped high-quality wafer 'has a DZ layer on the surface by the subsequent heat treatment, and has a sufficient density of BMD at the main body portion. At this time, it is preferable to use a nitrogen gas to be mixed with 1 〇 PPm or more and 1 5 Oppm or less. In the atmosphere gas, a gas obtained by mixing water having a concentration of 10 ppm or more and I50 ppm or less into the nitrogen gas can be used as an atmosphere gas to inject more voids into the wafer. Even at a low-temperature heat treatment, a bmD density equal to or higher than that in the case of performing an RTA heat treatment using an atmosphere of NH3 。 can be obtained. At this time, it is preferable to adjust the concentration of water mixed in the nitrogen gas by controlling the dew point of the nitrogen gas to prepare the atmosphere gas. Thus, by controlling the dew point of nitrogen gas, the adjustment of the water concentration to be mixed can be more easily performed. At this time, it is preferred to control the dew point of nitrogen to _ 6 〇〇 c or more - 38. (: In the following, the moisture of a concentration of 10 ppm or more and 15 〇 ppm or less is mixed into φ nitrogen gas to make the atmosphere gas. By controlling the dew point of the atmosphere to the above range, the moisture wave degree can be more easily adjusted to 1 (ppm). In the preferred range of 15Qppm or less, at this time, the phase oxy-rolling degree of the Shixia crystal garden to be subjected to the RTA heat treatment is preferably set to 9 ΡΡ π Χ ± l4 ppma or less. According to the RTA heat treatment of the present invention, even if the temperature is low, a sufficient amount of voids can be injected, and since it is possible to produce a wafer having no slip and high germanium density, it is preferable because it has no excessive deposition. 6 201025454 At this time, 'the enamel layer can be grown on the surface of the wonderful wafer after the heat treatment of the above-mentioned rta. If the dream wafer is heat-treated by the RTA of the present invention, the body portion has a sufficient amount of voids, and the surface is Good crystallinity, even in the production of tantalum wafers which are epitaxially grown at a good temperature, it is also preferable because it can cause good oxygen deposition, has a high BMD density, and can obtain a good epitaxial layer. According to the present invention, a ruthenium wafer having no slip, Dz layer and high BMd density can be manufactured at low cost without using a toxic gas such as helium. [Embodiment] Previously, a toxic gas such as NH3 or a high temperature was used. In the heat treatment, the void is injected into the wafer, but there is a problem of slippage, a problem in terms of cost, etc. 对此 In this regard, the present inventors have heat-treated the cavity without using NH3 or the like even at a lower temperature heat treatment. As a result of intensive research, it was found that a gas obtained by mixing a small amount of water into nitrogen gas as an atmosphere gas during the heat treatment of the RTA can be injected into the interior of the wafer even at a lower temperature. In order to investigate the appropriate amount of water, the inventors of the present invention performed an RTA heat treatment (1175 ° C / 30 seconds) on a ruthenium wafer under a nitrogen atmosphere containing various types of water rolling and an atmosphere containing NH 3 . Used to form 7 201025454 oxygen precipitates, which is the two-stage heat treatment of BMD (8 〇〇. (: / four hours, l 〇〇〇 ° C / sixteen hours), then investigate its BMD density, borrow The results are shown in Fig. 1. Fig. 1 is a table showing the relationship between the water concentration and the BMD density in nitrogen gas mixed as an atmosphere gas for RTA heat treatment. As can be seen from Fig. 1, since the RTA heat treatment temperature is lower, In pure nitrogen (N2), oxygen is not sufficiently precipitated. However, when 5 pprn (N2 + h20 (5 ppm)) or more of water is mixed into the nitrogen gas, good oxygen evolution occurs. Further, it is known that: In the range of ~15 ppm, the BMD density is higher than that of the strontium crystallized after the RTA heat treatment in the atmosphere gas (NH3/Ar) containing NH3 under the same heat treatment conditions. In addition, if the water concentration exceeds 250 ppm, the BMD density is greatly reduced. This is considered to be because an oxide film is formed due to moisture during the RTA heat treatment, and the amount of voids is reduced between the crystal lattices and the amount of voids is reduced. Will be suppressed for the sake of it. In the above, it is found that a gas having a concentration of 5 ppm or more and ❹ 250 ppm or less in nitrogen is preferably mixed with water having a concentration of 1 〇 ppm or more and 15 〇 ppm or less, and is used as an atmosphere gas for RTA heat treatment, even if It is a lower temperature, and a sufficient cavity can be injected to produce a silicon wafer having a high density of BMD layers, and the present invention has been completed. Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings, but the present invention is not limited to the embodiments. First, an example of a heat treatment furnace for RTA which can be used in the present invention is shown in Fig. 2 . In the present invention, since it is not necessary to use the toxic 8 such as NH3 or the like, the 2010-30454 gas towel can be used as a heat treatment furnace using substantially the same equipment as before. The heat treatment furnace 2G' is provided with a gas supply port 22 for supplying an atmosphere gas for plugging in the inlet of the Shixi wafer w, a gas discharge port 24 for discharging the atmosphere gas, and a field and a crucible for mounting The receiving body 23 of the dream wafer and the lamp 21» for heating the broken wafer W are placed on the silicon wafer w in the heat treatment furnace 20, and the atmosphere gas is supplied from the gas supply port 22, and the rta heat treatment is performed. In the present invention, a gas obtained by mixing water having a concentration of 5 ppm or more and 25 〇 ppm or less in nitrogen gas is used as the atmosphere gas in the RTA heat treatment using the heat treatment furnace as described above. In general, pure nitrogen has a moisture content of at least about 2 ppm. Previously, it was considered that the atmosphere containing no moisture caused void injection, so the water concentration of the pure gas was adjusted to be smaller β relative to Therefore, in the present invention, the rta enthalpy treatment is performed in an atmosphere in which a small amount of moisture in the range of the present invention is intentionally mixed into the air gas, whereby even a lower temperature heat treatment can be used. A nitrogen oxide film is formed on the surface of the wafer. By using nitrogen to react with helium atoms, voids can be efficiently injected into the interior of the dream wafer. Therefore, even if a toxic gas such as nh3 is not used in the atmosphere gas, a relatively low temperature heat treatment can be used to inject a sufficient amount of voids into the silicon wafer. By performing the RTA heat treatment of the present invention as described above, a high-quality, non-slip-free tantalum wafer having a sufficient BMD density inside can be manufactured at low cost. Further, it is preferable that the concentration of water mixed in the nitrogen gas is 1 〇 ppm or more and 9 201025454 150 ppm or less. A gas obtained by mixing water in the concentration range is used as an atmosphere gas, whereby a large number of voids can be injected. Even in the low-temperature heat treatment, the BMD density of the tantalum wafer after the RTA heat treatment is higher than that in the atmosphere using NH3, and therefore, a higher quality tantalum wafer can be manufactured. In this case, it is preferred to adjust the concentration of water mixed in the nitrogen gas by controlling the dew point of the nitrogen gas; preferably, the dew point of the nitrogen gas is controlled to be 60 ° C or more and 38 ° C or less, so that 1 〇 ppm or more and 150 ppm or less. The moisture of the indifference is mixed into the gas (nitrogen used in the semiconductor industry, the dew point is set below 70 ° C). Since the water concentration in the nitrogen gas used in the RTA heat treatment of the present invention is extremely small, the water concentration can be easily adjusted according to the method of controlling the dew point, and the above is preferable. Adjustments within the water concentration range have also become easier. ® W T ' & Table 1 shows the relationship between the dew point of nitrogen and the water concentration. 10 201025454 [Table 1]
露點（。〇 水分量(ppm) 露點（。〇 水分量(ppm) 露點rc) 水分量（ppm) 露點（。〇 水分量(ppm)丨 0 6032 -31 337.8 -62 8.117 -93 0.05468 -1 5553 -32 304.0 -63 7.067 -94 0.04522 2 5110 -33 273.4 -64 6.145 -95 0.03733 -3 4698 -34 245.6 -65 5.336 -96 0.03074 -4 4318 -35 220.5 -66 4.628 -97 0.02527 -5 3965 -36 197.7 -67 4.008 -98 0.02072 -6 3639 -37 177.1 -68 3.466 -99 0.01695 -7 3338 -38 158.6 -69 2.993 -100 0.01384 •8 3059 -39 141.8 -70 2.581 -101 0.01127 -9 2802 -40 126.7 71 2.223 -102 0.009156 -10 2565 -41 112.1 -72 1.911 -103 0.007421 -11 2346 -42 100.8 -73 1.641 -104 0.006000 -12 2145 -43 89.82 -74 1.407 -105 0.004839 -13 1959 -44 79.93 -75 1.204 -106 0.003893 -14 1788 -45 71.06 -76 1,029 •107 0.003123 -15 1631 -46 63.11 -77 0.8780 -108 0.002500 -16 1487 47 55.99 -78 0.7479 -109 0.001995 -17 1354 -48 49.62 -79 0.6361 -110 0.001588 -18 1233 -49 43.92 -80 0.5401 -111 0.001260 -19 1121 -50 38.84 -81 0.4578 -112 0.0009975 -20 1029 -51 34.31 -82 0.3874 -113 0.0007872 -21 925.3 -52 30.28 -83 0.3272 -114 0.0006195 -22 839.6 -53 26.68 -84 0.2759 -115 0.0004860 -23 761.3 -54 23.49 -85 0.2323 -116 0.0003801 -24 689.7 -55 20.66 -86 0.1952 -117 0.0002964 -25 624.4 -56 18.14 -87 0.1637 -118 0.0002304 -26 564.8 -57 15.91 -88 0.1370 -119 0.0001785 -27 510.5 -58 13.94 -89 0.1145 -120 0.0001378 -28 461.0 -59 12.20 -90 0.09544 -29 416.0 -60 10.67 -91 0.07946 -30 375.0 -61 9.31 -92 0.06597 如第1表所示可知，為了調整在本發明的水分濃度範 圍（5ppm以上250ppm以下）内，只要將氮氣的露點控制 在一65 °C以上一34°C以下即可，再者，為了調整在較佳的 11 201025454 水刀濃度範圍（l〇ppm以上15〇ppm以下）内只要將氮氣 的露點控制在一6CTC以上—380C以下即可。 作為施行如此的本發明的RTA熱處理之矽晶圓，並無 特別限定，但較佳是例如初期氧濃度為9ppma以上i4ppma 以下（日本電子工業發展協會；Japanese Electronic Industry Development Association ; jEIDA)的矽晶圓 β 即便是如此的較低氧濃度的矽晶圓，若是本發明的 φ RTA熱處理，即便低溫亦可注入充分的空洞量，製造出無 滑移、高BMD密度的矽晶圓，且無析出過多而較適宜。 又，關於如此的本發明的RTA熱處理條件，亦無特別 限疋，例如，能以20〜5〇°C /秒的條件來升溫，於11〇〇 °C〜 1200°C施行00秒以下的熱處理之後，以2〇〜5〇〇c/ 秒的條件進行降溫。 如此’若是本發明的rTA熱處理，即便是11〇〇〇c〜12〇〇 C這樣的較低溫的熱處理’亦可注入空洞，因此，矽晶圓 ❷不會發生滑移，而可進行良好的熱處理。又，以超過12〇〇 c的溫度進行熱處理的情況時，亦可使熱處理時間未滿1〇 秒，且即便是短時間，亦可注入充分的空洞。又，亦可更 加快降溫速度，凍結更多的空洞。 如以上所述，被施行本發明的rTA熱處理後的矽晶 圓’係無滑移、具有充分的空洞量，因此，藉由後製程的 使氧析出的熱處理’成為一種高品質的矽晶圓，在其主體 部具有5xl08/cm3以上’甚至是2xl〇9/cm3以上這樣的充 分高的BMD密度’且在表面具有層。 12 201025454 而且，被施行本發明的RTA熱處理後之矽晶圓，^ ’' 四較佳 是在其表面形成蟲晶層。 若是被施行本發明的RTA熱處理後的矽晶圓，gll ^ Ί因具 有充分量的空洞，則即便是在高溫下進行磊晶成長的 妇 / B日 圓的製造中，亦引起良好的氧析出，可作成—種具 會 、有尚 BMD密度的蟲晶晶圓，所以是較佳的。 以下，表示實施例與比較例來更具體地說明本發明， ® 但本發明不限定於這些例子。 (實施例、比較例） 準備初期氧濃度為12ppma(JEDIA)的矽晶圓，來作 為欲施行熱處理的矽晶圓。 作為氣氛氣體，使混入氮氣中的水分濃度於〇ppm〜 300ppm的範圍作變化，並以RTA熱處理溫度1175°C、熱 處理時間30秒、升溫速度50°C /秒、降溫速度33°C /秒 ❹的條件’對所準備的矽晶圓施行RTA熱處理。又，以相同 條件，但使用NH3 / Ar的混合氣體來作為氣氛氣體，對矽 晶圓施行熱處理。 為了對於如上述般地施行RTA熱處理後的矽晶圓進行 BMD評價，而施行二階段熱處理（8〇(TC/四小時、1000 C /十六小時）。劈開（cleavage)、蚀刻此二階段熱處理後的 發晶圓，觀察從表層至500 為止的BMD層，並測定 BMD密度。第4圖係觀察BMD層而得到的圖。 在第1圖與第2表中，表示BMD密度的測定結果。 13 201025454 [第2表] RTA溫度 (°C) RTA (秒） 水分濃度 (ppm) 升溫速度 (°C / 秒） 降溫速度 (。(：/ 秒） BMD密度 (cm'3) 備註 1175 30 0 50 33 2.0E+07 n2 1175 30 5 50 33 6.2E+08 N2+H20 1175 30 10 50 33 2.5E+09 N2+H2O 1175 30 25 50 33 6.6E+09 N2+H2O 1175 30 50 50 33 6.6E+09 N2+H2O 1175 30 75 50 33 6.5E+09 N2+H2O 1175 30 100 50 33 5.0E+09 n2+h2o 1175 30 125 50 33 6.8E+09 n2+h2o 1175 30 150 50 33 2.6E+09 N2+H20 1175 30 200 50 33 1.1E+09 n2+h2o 1175 30 250 50 33 5.6E+08 n2+h2o 1175 30 300 50 33 1.6E+08 N2+H20 1175 30 0 50 33 2.3E+09 NH3/Ar 表層〜150 為止的平均值 由第1圖、第2表可知，在純粹的氮氣（N2)的氣氛 下進行熱處理後的情況時，其BMD密度非常小，但在使水 分混入氮氣後而成的氣氛氣體（N2+H2〇(5ppm以上）） 中進行的情況時，其BMD密度高，於RTA熱處理中，被 •進行充分的空洞注入。 又，可知，若水分濃度超過25Oppm，則氧化膜會被形 成，由於晶格間矽的注入量變多，所以空洞會減少，因此 BMD密度會變得非常小。 在RTA熱處理中，於實施例（N2+ H20( 5〜25 0ppm)) 與比較例（NH3 / Ar )，雖然皆於矽晶圓表面形成有氮氧化 膜或氮化膜，但是在實施例中係約lnm的厚度，與比較例 相較，其膜厚較薄。但是，亦有實施例較比較例的BMD密 14 201025454 度高的情況。此係因空洞注入量越多則bmd的尺寸越小， 因尺寸小的BMD容易於之後的熱處理製程中消失，因此可 知，實施例，相較比較例（NH3 / Ar )，為適度的空洞注入 量0 由此可知’施行本發明的RTA熱處理後的矽晶圓，適 用於必須高溫熱處理的磊晶層成長用晶圓。 另外，本發明並未被限定於上述實施形態。上述實施 形態僅為例示，凡是與被記載於本發明的申請專利範圍中 ❹的技術性思想’具有實質上相同的構成，產生相同的作用 效果者，皆應包含於本發明的技術性範圍内。 參 15 201025454 【圖式簡單說明】 第1圖係表示在RTA熱處理之際，混入氮氣中的水分 濃度，與在該RTA熱處理後，經施行二階段熱處理後的矽 晶圓的BMD密度的關係的圖表。 第2圖係表示可用於本發明的RTA熱處理中的熱處理 爐的一例的概略圖。 第3圖係表示具有被施行RTA熱處理後的DZ層與 BMD層的碎晶圓的一例的概略圖。 第4圖係觀察先施行RTA熱處理，然後進行二階段熱 處理之後的矽晶圓的BMD層而得到的圖。 【主要元件符號說明】 25 :蓋 31 : DZ層（無缺陷層） 32 : BMD 層 W :矽晶圓 20 :熱處理爐 21 :燈 22 :氣體供給口 φ 23 :承受體 24 :氣體排出口Dew point (.hydrometer component (ppm) dew point (.hydrophobic component (ppm) dew point rc) moisture content (ppm) dew point (.hydrometer component (ppm) 丨0 6032 -31 337.8 -62 8.117 -93 0.05468 -1 5553 -32 304.0 -63 7.067 -94 0.04522 2 5110 -33 273.4 -64 6.145 -95 0.03733 -3 4698 -34 245.6 -65 5.336 -96 0.03074 -4 4318 -35 220.5 -66 4.628 -97 0.02527 -5 3965 -36 197.7 -67 4.008 -98 0.02072 -6 3639 -37 177.1 -68 3.466 -99 0.01695 -7 3338 -38 158.6 -69 2.993 -100 0.01384 •8 3059 -39 141.8 -70 2.581 -101 0.01127 -9 2802 -40 126.7 71 2.223 -102 0.009156 -10 2565 -41 112.1 -72 1.911 -103 0.007421 -11 2346 -42 100.8 -73 1.641 -104 0.006000 -12 2145 -43 89.82 -74 1.407 -105 0.004839 -13 1959 -44 79.93 -75 1.204 -106 0.003893 -14 1788 -45 71.06 -76 1,029 •107 0.003123 -15 1631 -46 63.11 -77 0.8780 -108 0.002500 -16 1487 47 55.99 -78 0.7479 -109 0.001995 -17 1354 -48 49.62 -79 0.6361 -110 0.001588 -18 1233 -49 43.92 -80 0.5401 -111 0.001260 -19 1121 -50 38.84 -81 0.4578 -112 0.0009975 -20 1029 -51 34. 31 -82 0.3874 -113 0.0007872 -21 925.3 -52 30.28 -83 0.3272 -114 0.0006195 -22 839.6 -53 26.68 -84 0.2759 -115 0.0004860 -23 761.3 -54 23.49 -85 0.2323 -116 0.0003801 -24 689.7 -55 20.66 - 86 0.1952 -117 0.0002964 -25 624.4 -56 18.14 -87 0.1637 -118 0.0002304 -26 564.8 -57 15.91 -88 0.1370 -119 0.0001785 -27 510.5 -58 13.94 -89 0.1145 -120 0.0001378 -28 461.0 -59 12.20 -90 0.09544 -29 416.0 -60 10.67 -91 0.07946 -30 375.0 -61 9.31 -92 0.06597 As shown in Table 1, it is understood that the dew point of nitrogen gas is controlled in order to adjust the water concentration range (5 ppm or more and 250 ppm or less) of the present invention. A 65 ° C or more and a 34 ° C or less can be, in addition, in order to adjust the preferred 11 201025454 water knife concentration range (l 〇 ppm and 15 〇 ppm or less) as long as the nitrogen dew point is controlled above 6 CTC - It can be below 380C. The ruthenium wafer to which the RTA heat treatment of the present invention is applied is not particularly limited, but is preferably, for example, a twin crystal having an initial oxygen concentration of 9 ppma or more and i4 ppma or less (Japanese Electronic Industry Development Association; jEIDA). Round β Even with such a low oxygen concentration ruthenium wafer, if the φ RTA heat treatment of the present invention is performed, a sufficient void amount can be injected even at a low temperature to produce a ruthenium wafer having no slip and high BMD density, and no precipitation Too much and more appropriate. Further, the RTA heat treatment conditions of the present invention are not particularly limited, and for example, the temperature can be raised at a temperature of 20 to 5 ° C / sec, and the pressure is maintained at 11 ° C to 1200 ° C for 00 seconds or less. After the heat treatment, the temperature was lowered under conditions of 2 Torr to 5 〇〇 c / sec. Thus, in the case of the rTA heat treatment of the present invention, even a relatively low temperature heat treatment such as 11 〇〇〇 c to 12 〇〇 C can be injected into the cavity, so that the ruthenium wafer ❷ does not slip, and can be performed well. Heat treatment. Further, when the heat treatment is carried out at a temperature exceeding 12 〇〇 c, the heat treatment time may be less than 1 〇 second, and a sufficient cavity may be injected even in a short time. In addition, it can speed up the cooling rate and freeze more holes. As described above, the tantalum wafer after the heat treatment of the rTA of the present invention has no slip and has a sufficient void amount, and therefore, the heat treatment for oxygen deposition by the post-process becomes a high-quality tantalum wafer. It has a sufficiently high BMD density of 5xl08/cm3 or more 'even 2xl〇9/cm3 or more in its main body portion and has a layer on the surface. 12 201025454 Moreover, the tantalum wafer after the heat treatment of the RTA of the present invention is preferably formed on the surface of the wafer. In the case of the tantalum wafer which has been subjected to the RTA heat treatment of the present invention, gll^Ί has a sufficient amount of voids, and even in the production of a woman/B yen which undergoes epitaxial growth at a high temperature, good oxygen deposition is caused. It can be made into a kind of insect crystal wafer with a BMD density, so it is preferable. Hereinafter, the present invention will be described more specifically by way of examples and comparative examples, but the present invention is not limited to these examples. (Examples and Comparative Examples) A tantalum wafer having an initial oxygen concentration of 12 ppma (JEDIA) was prepared as a tantalum wafer to be subjected to heat treatment. As the atmosphere gas, the concentration of water mixed in the nitrogen gas was changed in the range of 〇 ppm to 300 ppm, and the heat treatment temperature was 1175 ° C, the heat treatment time was 30 seconds, the temperature increase rate was 50 ° C / sec, and the temperature drop rate was 33 ° C / sec. The condition of ❹ 'The RTA heat treatment was applied to the prepared ruthenium wafer. Further, under the same conditions, a mixed gas of NH3 / Ar was used as an atmosphere gas to heat-treat the silicon wafer. In order to perform BMD evaluation on the tantalum wafer after the RTA heat treatment as described above, a two-stage heat treatment (8 〇 (TC/four hours, 1000 C / sixteen hours) was performed. The two-stage heat treatment was performed by cleavage and etching. In the subsequent wafer, the BMD layer from the surface layer to 500 was observed, and the BMD density was measured. Fig. 4 is a view showing the BMD layer. The first and second tables show the measurement results of the BMD density. 13 201025454 [Table 2] RTA temperature (°C) RTA (seconds) Water concentration (ppm) Heating rate (°C / sec) Cooling rate (. (: / sec) BMD density (cm'3) Remark 1175 30 0 50 33 2.0E+07 n2 1175 30 5 50 33 6.2E+08 N2+H20 1175 30 10 50 33 2.5E+09 N2+H2O 1175 30 25 50 33 6.6E+09 N2+H2O 1175 30 50 50 33 6.6E +09 N2+H2O 1175 30 75 50 33 6.5E+09 N2+H2O 1175 30 100 50 33 5.0E+09 n2+h2o 1175 30 125 50 33 6.8E+09 n2+h2o 1175 30 150 50 33 2.6E+09 N2+H20 1175 30 200 50 33 1.1E+09 n2+h2o 1175 30 250 50 33 5.6E+08 n2+h2o 1175 30 300 50 33 1.6E+08 N2+H20 1175 30 0 50 33 2.3E+09 NH3/ The average value of Ar surface layer ~150 is determined by In the case of the heat treatment in a pure nitrogen (N2) atmosphere, the BMD density is very small, but the atmosphere gas (N2+H2〇 (5 ppm) obtained by mixing water with nitrogen is known. In the case of the above), the BMD density is high, and during the RTA heat treatment, sufficient void injection is performed. Further, it can be seen that if the water concentration exceeds 25 ppm, the oxide film is formed due to intergranular enthalpy. Since the amount of injection is increased, the voids are reduced, so the BMD density becomes very small. In the RTA heat treatment, the examples (N2+H20 (5 to 25 0 ppm)) and the comparative examples (NH3 / Ar), although both are twinned An oxynitride film or a nitride film is formed on the surface of the circle, but in the embodiment, the thickness is about 1 nm, and the film thickness is thinner than that of the comparative example. However, there are also BMD densely compared with the comparative example of the embodiment. High situation. This is because the larger the amount of void injection, the smaller the size of bmd, and the smaller the size of BMD is likely to disappear in the subsequent heat treatment process. Therefore, it can be seen that the embodiment is a moderate cavity injection compared to the comparative example (NH3 / Ar ). The amount 0 indicates that the tantalum wafer after the RTA heat treatment of the present invention is applied to a wafer for epitaxial layer growth which requires high-temperature heat treatment. Further, the present invention is not limited to the above embodiment. The above-described embodiments are merely illustrative, and those having substantially the same configuration as the technical idea described in the scope of the patent application of the present invention and having the same effects are included in the technical scope of the present invention. . Reference 15 201025454 [Simple description of the drawing] Fig. 1 shows the relationship between the concentration of water mixed in nitrogen gas during the heat treatment of RTA and the BMD density of the tantalum wafer after the heat treatment of the RTA. chart. Fig. 2 is a schematic view showing an example of a heat treatment furnace which can be used in the RTA heat treatment of the present invention. Fig. 3 is a schematic view showing an example of a broken wafer having a DZ layer and a BMD layer which have been subjected to RTA heat treatment. Fig. 4 is a view showing a BMD layer of a tantalum wafer which was subjected to an RTA heat treatment and then subjected to a two-stage heat treatment. [Description of main component symbols] 25: Cover 31: DZ layer (defect-free layer) 32: BMD layer W: Silicon wafer 20: Heat treatment furnace 21: Lamp 22: Gas supply port φ 23: Acceptance body 24: Gas discharge port