JP2019127416A - Production method of silicon carbide single crystal and silicon carbide single crystal ingot - Google Patents
Production method of silicon carbide single crystal and silicon carbide single crystal ingot Download PDFInfo
- Publication number
- JP2019127416A JP2019127416A JP2018009990A JP2018009990A JP2019127416A JP 2019127416 A JP2019127416 A JP 2019127416A JP 2018009990 A JP2018009990 A JP 2018009990A JP 2018009990 A JP2018009990 A JP 2018009990A JP 2019127416 A JP2019127416 A JP 2019127416A
- Authority
- JP
- Japan
- Prior art keywords
- silicon carbide
- single crystal
- seed crystal
- carbide single
- crystal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000013078 crystal Substances 0.000 title claims abstract description 220
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 title claims abstract description 159
- 229910010271 silicon carbide Inorganic materials 0.000 title claims abstract description 158
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 37
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 96
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 46
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 43
- 239000010439 graphite Substances 0.000 claims abstract description 43
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 41
- 229910001873 dinitrogen Inorganic materials 0.000 claims abstract description 13
- 239000002994 raw material Substances 0.000 claims abstract description 11
- 238000005092 sublimation method Methods 0.000 claims abstract description 11
- 239000007789 gas Substances 0.000 claims abstract description 10
- 238000000859 sublimation Methods 0.000 claims abstract description 8
- 230000008022 sublimation Effects 0.000 claims abstract description 8
- 238000007689 inspection Methods 0.000 claims description 23
- 238000000034 method Methods 0.000 claims description 12
- 238000007872 degassing Methods 0.000 claims description 3
- 238000009849 vacuum degassing Methods 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract description 29
- 230000035515 penetration Effects 0.000 abstract description 16
- 239000000126 substance Substances 0.000 description 8
- 239000000758 substrate Substances 0.000 description 8
- 239000000853 adhesive Substances 0.000 description 5
- 230000001070 adhesive effect Effects 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 3
- 230000000149 penetrating effect Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Landscapes
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
本発明は、炭化珪素単結晶の製造方法と、それに用いる炭化珪素単結晶インゴットに関する。 The present invention relates to a method for producing a silicon carbide single crystal and a silicon carbide single crystal ingot used therefor.
半導体材料である炭化珪素（ＳｉＣ）は、デバイス用基板として広く使用されているＳｉ（珪素）に比べてバンドギャップが大きいことから、単結晶ＳｉＣ基板を使用してパワーデバイス、高周波デバイス、高温動作デバイス等を作製する研究が行われている。 Silicon carbide (SiC), which is a semiconductor material, has a large band gap compared to Si (silicon) widely used as a substrate for devices. Therefore, power devices, high-frequency devices, high-temperature operation using single crystal SiC substrates Research to fabricate devices and the like is underway.
ＳｉＣデバイスは、昇華法等で成長させた炭化珪素のバルク単結晶から加工して得られたＳｉＣ単結晶基板上に、化学的気相成長法（Ｃｈｅｍｉｃａｌ Ｖａｐｏｒ Ｄｅｐｏｓｉｔｉｏｎ：ＣＶＤ）等によってデバイスの活性領域となるエピタキシャル層（膜）を形成した、ＳｉＣエピタキシャルウェハを用いて作製される。 The SiC device is an active region of the device by chemical vapor deposition (CVD) or the like on a SiC single crystal substrate obtained by processing from a bulk single crystal of silicon carbide grown by a sublimation method or the like. It is produced using a SiC epitaxial wafer in which an epitaxial layer (film) to be formed is formed.
炭化珪素のバルク単結晶を製造する方法の一つとして、昇華法が広く知られている。昇華法は、黒鉛製の坩堝内に炭化珪素単結晶からなる種結晶を配置し、坩堝を加熱することで坩堝内の原料粉末から昇華した昇華ガスを種結晶に供給し、種結晶をより大きなＳｉＣ単結晶へ成長させる方法である。種結晶を黒鉛部材に接着して配置させる際、接着面に気泡や異物が存在すると種結晶裏面から貫通欠陥Ｄが伸長することがある。（特許文献１、特許文献２）。これは種結晶裏面からの再昇華が原因と考えられており、マイクロパイプのようにウェハに貫通穴が空いてしまうこともある。特許文献１では、種結晶裏面と坩堝蓋裏面（黒鉛部材）を平坦化処理した後、接着せずに物理的に密着させ、機械的に固定することにより、接着時の気泡の発生を防いでいる。しかし、機械的固定は再現よく行うことが難しい。また、特許文献２では種結晶を接着する工程で、接着剤を乾燥、硬化させる熱処理を特定の条件で行うことにより接着不良を防ぐとしているが、接着時に気泡や異物を完全に除去することは難しい。 As one method for producing a silicon carbide bulk single crystal, a sublimation method is widely known. In the sublimation method, a seed crystal made of silicon carbide single crystal is placed in a crucible made of graphite, and the sublimation gas sublimated from the raw material powder in the crucible is supplied to the seed crystal by heating the crucible, and the seed crystal is made larger This is a method of growing into a SiC single crystal. When the seed crystal is bonded to the graphite member and disposed, if there are bubbles or foreign substances on the bonding surface, the penetration defect D may extend from the back surface of the seed crystal. (Patent Document 1, Patent Document 2). This is considered to be caused by resublimation from the back surface of the seed crystal, and a through hole may be formed in the wafer like a micropipe. In Patent Document 1, after the seed crystal back surface and the lid back surface (graphite member) are subjected to flattening treatment, physical adhesion is made without adhesion and mechanical fixation is performed to prevent the generation of air bubbles during adhesion. Yes. However, it is difficult to perform mechanical fixation with good reproducibility. Moreover, in the step of bonding a seed crystal in Patent Document 2, adhesion failure is prevented by performing heat treatment to dry and cure the adhesive under specific conditions in the step of bonding a seed crystal, but it is possible to completely remove air bubbles and foreign substances during bonding. difficult.
炭化珪素単結晶は電子デバイスの基板として用いられるため、通常は窒素等の不純物原子がドーピングされた導電性の炭化珪素単結晶を作成する。特に、パワーデバイスの基板として用いる場合には、低抵抗であることが求められ、高濃度の窒素がドーピングされる。通常、導電性の炭化珪素単結晶を成長するための種結晶としては、得られる単結晶と同程度にドーピングされた炭化珪素単結晶からなる種結晶が用いられる。特許文献３には、種結晶と種結晶上に成長した成長結晶との不純物添加元素濃度比を５倍以内とする製造方法が記載されている。 Since the silicon carbide single crystal is used as a substrate for an electronic device, a conductive silicon carbide single crystal doped with impurity atoms such as nitrogen is usually prepared. In particular, when used as a power device substrate, it is required to have a low resistance and is doped with a high concentration of nitrogen. Usually, as a seed crystal for growing a conductive silicon carbide single crystal, a seed crystal composed of a silicon carbide single crystal doped to the same extent as the obtained single crystal is used. Patent Document 3 describes a manufacturing method in which the impurity-added element concentration ratio between the seed crystal and the grown crystal grown on the seed crystal is 5 times or less.
図３は、炭化珪素単結晶４０の成長中における、炭化珪素種結晶５０の裏面５０ｂ側周辺の断面の顕微鏡画像である。画像から、目視でも確認できるような多数の大きな貫通欠陥Ｄが種結晶裏面から伸長していることが分かる。貫通欠陥Ｄは種結晶裏面を起点として伸びており、種結晶と黒鉛部材を接着した時に生じた気泡や異物が原因と考えられる。このような貫通欠陥Ｄがあるウェハ上に良好なエピタキシャル膜を作製することは困難である。 FIG. 3 is a microscope image of a cross section around the back surface 50 b side of silicon carbide seed crystal 50 during growth of silicon carbide single crystal 40. From the image, it can be seen that a large number of large penetration defects D, which can be confirmed visually, extend from the back surface of the seed crystal. The penetration defects D are extended starting from the back surface of the seed crystal, and are considered to be caused by air bubbles or foreign substances generated when bonding the seed crystal and the graphite member. It is difficult to fabricate a good epitaxial film on a wafer having such penetration defects D.
現状の技術では、例えば超音波測定等を行って、大きな空隙を検出することは可能であるが、気泡や異物等による小さい欠陥を検出することは難しい。また、上述の様に低抵抗の炭化珪素単結晶の種結晶は、高濃度の窒素がドーピングされているため、可視光に対して不透明であり、種結晶を黒鉛部材に接着した後に、種結晶を通して接着部分を直接見て良否を判定することは困難である。そのため、種結晶を黒鉛部材に接着した段階で小さい気泡や異物などの不良を含んだ状態であっても、そのまま用いて結晶成長がなされることになり、それに起因した貫通欠陥Ｄの発生を抑制することは難しい。 With the current technology, for example, it is possible to detect a large gap by performing ultrasonic measurement or the like, but it is difficult to detect a small defect such as a bubble or a foreign substance. Also, as described above, the low resistance silicon carbide single crystal seed crystal is opaque to visible light because it is doped with high concentration of nitrogen, and after bonding the seed crystal to the graphite member, the seed crystal is It is difficult to judge the quality by directly looking at the bonded portion through the through hole. Therefore, even when the seed crystal is adhered to the graphite member in the state including defects such as small air bubbles or foreign matter, crystal growth is performed as it is, and the generation of penetration defects D resulting therefrom is suppressed Difficult to do.
本発明は、かかる事情に鑑みてなされたものであり、昇華法による炭化珪素の単結晶成長時に、種結晶と黒鉛部材との間に接着不良がある状態でそのまま用いてしまうことを防ぎ、種結晶裏面からの貫通欠陥が伸長する問題を回避することを可能とする、炭化珪素単結晶の製造方法を提供することを目的とする。また、この炭化珪素単結晶の製造方法で用いる種結晶を有する、炭化珪素単結晶インゴットを提供することを目的とする。 The present invention has been made in view of the above circumstances, and prevents the use of the adhesion failure between the seed crystal and the graphite member as it is when the silicon carbide single crystal is grown by the sublimation method, thereby preventing the seed from being used. An object of the present invention is to provide a method for producing a silicon carbide single crystal, which can avoid the problem of extending through defects from the back surface of the crystal. Another object of the present invention is to provide a silicon carbide single crystal ingot having a seed crystal used in this method for producing a silicon carbide single crystal.
上記課題を解決するため、本発明は以下の手段を採用している。 In order to solve the above problems, the present invention employs the following means.
（１）本発明の一態様に係る炭化珪素単結晶の製造方法は、昇華法による炭化珪素単結晶の製造方法であって、坩堝内の黒鉛部材に、窒素濃度を５×１０１７ｃｍ−３以下に抑えた炭化珪素種結晶を取り付け、前記黒鉛部材と前記炭化珪素種結晶との界面の状態を検査する第１界面検査工程と、炭化珪素原料の昇華ガスおよび窒素ガスを供給し、３×１０１８ｃｍ−３以上の濃度で窒素ドープされた炭化珪素単結晶を成長させる単結晶成長工程と、を順に有する。 (1) The method for producing a silicon carbide single crystal according to one aspect of the present invention is a method for producing a silicon carbide single crystal by a sublimation method, wherein the nitrogen concentration in the graphite member in the crucible is 5 × 10 17 cm −3. A silicon carbide seed crystal suppressed below is attached, a first interface inspection step for inspecting an interface state between the graphite member and the silicon carbide seed crystal, a sublimation gas and a nitrogen gas of a silicon carbide raw material are supplied, and 3 × And a single crystal growth step of growing a silicon carbide single crystal doped with nitrogen at a concentration of 10 18 cm −3 or more.
（２）前記（１）に記載の炭化珪素単結晶の製造方法において、前記炭化珪素種結晶として、厚さが１ｍｍ以上のものを用いることができる。 (2) In the method for producing a silicon carbide single crystal according to (1), a silicon carbide seed crystal having a thickness of 1 mm or more can be used.
（３）前記（１）または（２）のいずれかに記載の炭化珪素単結晶の製造方法の前記第１界面検査工程において、前記黒鉛部材と前記炭化珪素種結晶との界面で気泡が検出された場合に、真空脱泡または加圧脱泡を行って前記気泡を除去することができる。 (3) In the first interface inspection step of the method for manufacturing a silicon carbide single crystal according to any one of (1) and (2), bubbles are detected at an interface between the graphite member and the silicon carbide seed crystal. The bubbles can be removed by vacuum degassing or pressure degassing.
（４）前記（１）〜（３）のいずれか一つに記載の炭化珪素単結晶の製造方法において、前記第１界面検査工程において、前記黒鉛部材と前記炭化珪素種結晶との界面で異物が検出された場合に、一旦、前記炭化珪素種結晶を前記黒鉛部材から取り外し、前記異物を除去した上で、再度取り付けることができる。 (4) In the method for manufacturing a silicon carbide single crystal according to any one of (1) to (3), in the first interface inspection step, foreign matter is generated at an interface between the graphite member and the silicon carbide seed crystal. Is detected, the silicon carbide seed crystal is once removed from the graphite member, the foreign matter is removed, and the silicon carbide seed crystal can be attached again.
（５）前記（１）〜（４）のいずれか一つに記載の炭化珪素単結晶の製造方法において、窒素濃度が５×１０１７ｃｍ−３以下の低ドープ領域が設けられた、炭化珪素単結晶のインゴットを準備し、前記低ドープ領域の部分を前記インゴットから切り出し、前記炭化珪素種結晶として用いることができる。 (5) In the method of producing a silicon carbide single crystal according to any one of the above (1) to (4), silicon carbide provided with a low doped region having a nitrogen concentration of 5 × 10 17 cm −3 or less. A single crystal ingot may be prepared, and a portion of the low doped region may be cut out from the ingot and used as the silicon carbide seed crystal.
（６）前記（１）〜（５）のいずれか一つに記載の炭化珪素単結晶の製造方法において、前記単結晶成長工程の後に、前記炭化珪素種結晶と、その上に成長した前記炭化珪素単結晶インゴットとを前記黒鉛部材から取り外し、前記炭化珪素種結晶側から、前記炭化珪素種結晶と前記炭化珪素単結晶との界面の状態を検査する第２界面検査工程を、さらに有することができる。 (6) In the method for producing a silicon carbide single crystal according to any one of (1) to (5), after the single crystal growth step, the silicon carbide seed crystal and the carbonized carbon grown on the silicon carbide seed crystal. The method further includes a second interface inspection step of removing the silicon single crystal ingot from the graphite member and inspecting the state of the interface between the silicon carbide seed crystal and the silicon carbide single crystal from the silicon carbide seed crystal side. it can.
（７）本発明の一態様に係る炭化珪素単結晶インゴットは、窒素濃度が５×１０１７ｃｍ−３以下の領域、および窒素濃度が３×１０１８ｃｍ−３以上の領域が設けられている。 (7) The silicon carbide single crystal ingot according to one aspect of the present invention is provided with a region having a nitrogen concentration of 5 × 10 17 cm −3 or less and a region having a nitrogen concentration of 3 × 10 18 cm −3 or more. .
本発明で炭化珪素単結晶の成長に用いる種結晶は、窒素濃度が５×１０１７ｃｍ−３以下に抑えられているため、その一方の側において反対側の状態を目視できる程度に透明な状態である。したがって、種結晶を黒鉛部材に取り付けた時点で、種結晶の裏側を目視し、種結晶と黒鉛部材との界面の状態、具体的には、そこに種結晶裏面からの貫通欠陥（マクロ欠陥）の発生因子である気泡や異物等が存在しているかどうかを、検査することができる。 The seed crystal used for growing the silicon carbide single crystal in the present invention has a nitrogen concentration of 5 × 10 17 cm −3 or less, so the transparent state is such that the state on the opposite side can be visually recognized on one side thereof. It is. Therefore, when the seed crystal is attached to the graphite member, the back side of the seed crystal is visually observed, and the state of the interface between the seed crystal and the graphite member, specifically, a penetration defect (macro defect) from the back surface of the seed crystal It can be inspected whether air bubbles or foreign substances that are the cause of
検査の結果、気泡が存在している場合には真空脱泡または加圧脱泡を行って除去し、異物等が存在している場合には一度接着面を剥がして異物をピンセット等で除去することにより、黒鉛部材との界面に気泡や異物がない状態で、種結晶上に炭化珪素単結晶を成長させることが可能となる。このようにして、種結晶裏面からの貫通欠陥の発生因子を、製造プロセスの早い段階で発見して除去することにより、種結晶裏面から伸長する貫通欠陥に起因した、基底面転位の発生の問題を回避することができ、最終製品として高品質のＳｉＣデバイスを得ることができる。 If air bubbles are present as a result of the inspection, vacuum defoaming or pressure defoaming is performed to remove them. If foreign matter is present, the adhesive surface is peeled off once and the foreign matter is removed with tweezers. This makes it possible to grow a silicon carbide single crystal on the seed crystal in a state where there are no bubbles or foreign matters at the interface with the graphite member. In this way, the problem of the occurrence of basal plane dislocations caused by the penetrating defects extending from the back surface of the seed crystal by finding and removing the generation factor of the threading defect from the back surface of the seed crystal at an early stage of the manufacturing process. Can be avoided, and a high-quality SiC device can be obtained as a final product.
また、本発明の炭化珪素単結晶インゴットには、窒素濃度が５×１０１７ｃｍ−３以下の領域が設けられているため、この部分を切り出し、炭化珪素の単結晶成長用の種結晶として利用することができる。 In addition, since the silicon carbide single crystal ingot according to the present invention is provided with a region having a nitrogen concentration of 5 × 10 17 cm −3 or less, this portion is cut out and used as a seed crystal for single crystal growth of silicon carbide. can do.
以下、本発明について、図を適宜参照しながら詳細に説明する。以下の説明で用いる図は、本発明の特徴を分かりやすくするために、便宜上特徴となる部分を拡大して示している場合があり、各構成要素の寸法比率等は実際とは異なっていることがある。また、以下の説明において例示される材料、寸法等は一例であって、本発明はそれらに限定されるものではなく、本発明の効果を奏する範囲で適宜変更して実施することが可能である。 Hereinafter, the present invention will be described in detail with appropriate reference to the drawings. In the drawings used in the following description, in order to make the features of the present invention easier to understand, portions that become features may be shown in an enlarged form for convenience, and the dimensional ratios and the like of each component are different from actual ones. There is. In addition, the materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited to them, and can be appropriately modified and implemented within the scope of the effects of the present invention. .
図１は、本発明の一実施形態に係る、炭化珪素単結晶の製造装置１００の縦断面図であり、炭化珪素単結晶１０のインゴット（炭化珪素単結晶インゴット）が形成されている状態を示している。炭化珪素単結晶の製造装置１００は、少なくとも、坩堝１０１と、坩堝１０１内の一端側に配された炭化珪素種結晶（シード）２０が配置される黒鉛部材１０２と、坩堝１０１の外壁を囲むコイル１０３とを備え、坩堝１０１内の他の一端側に、原料３０が収容されるように構成されている。炭化珪素単結晶の製造装置１００は、さらに、黒鉛部材１０２から原料３０に向けて拡径するテーパーガイド１０４を備えていることが好ましい。また、炭化珪素単結晶の製造装置１００は、坩堝１０１とコイル１０３との間に、コイル１０３の誘導加熱により発熱する発熱体（不図示）を有していてもよい。 FIG. 1 is a longitudinal sectional view of a silicon carbide single crystal manufacturing apparatus 100 according to an embodiment of the present invention, showing a state in which an ingot of silicon carbide single crystal 10 (silicon carbide single crystal ingot) is formed. ing. Silicon carbide single crystal manufacturing apparatus 100 includes at least crucible 101, graphite member 102 on which silicon carbide seed crystal (seed) 20 disposed on one end side in crucible 101 is disposed, and a coil surrounding the outer wall of crucible 101. 103, and the other end of the crucible 101 is configured to accommodate the raw material 30. It is preferable that silicon carbide single crystal manufacturing apparatus 100 further includes a taper guide 104 whose diameter increases from graphite member 102 toward raw material 30. In addition, silicon carbide single crystal manufacturing apparatus 100 may include a heating element (not shown) that generates heat by induction heating of coil 103 between crucible 101 and coil 103.
炭化珪素単結晶の製造装置１００は、コイル１０３に交流電流を流すことによって、坩堝１０１が加熱され、原料３０から昇華ガス（原料ガス）が発生し、この昇華ガスが、テーパーガイド１０４に沿って、黒鉛部材１０２上の炭化珪素種結晶２０に供給されるように構成されている。炭化珪素種結晶２０に昇華ガスが供給されることにより、炭化珪素種結晶２０の表面に炭化珪素単結晶１０のインゴットが結晶成長することになる。 In silicon carbide single crystal manufacturing apparatus 100, by applying an alternating current to coil 103, crucible 101 is heated, and sublimation gas (raw material gas) is generated from raw material 30, and this sublimated gas flows along tapered guide 104. The silicon carbide seed crystal 20 on the graphite member 102 is supplied. By supplying the sublimation gas to silicon carbide seed crystal 20, an ingot of silicon carbide single crystal 10 grows on the surface of silicon carbide seed crystal 20.
図２（ａ）〜（ｄ）は、本発明の一実施形態に係る炭化珪素単結晶の製造工程のフローを示す図であり、各工程における、炭化珪素単結晶１０のインゴットの周辺部分１０５（図１）を拡大したものである。図２（ａ）〜（ｄ）を用い、炭化珪素単結晶の製造方法について、以下に説明する。 FIGS. 2A to 2D are views showing a flow of a manufacturing process of a silicon carbide single crystal according to one embodiment of the present invention, and a peripheral portion 105 ( Fig. 1) is an enlarged view. The manufacturing method of a silicon carbide single crystal is demonstrated below using FIG. 2 (a)-(d).
（種結晶準備工程）
まず、本発明の炭化珪素単結晶の製造に用いる種結晶を準備する。図２（ａ）に示すように、黒鉛部材１０２に、カーボン接着剤等を用いて炭化珪素種結晶２０Ａを取り付け、昇華法によって、炭化珪素種結晶２０Ａの表面に炭化珪素単結晶１０Ａを成長させる。この種結晶準備工程における炭化珪素単結晶成長中に、窒素ガスを供給せずに成長を行う（窒素ドープを行わない）。通常の炭化珪素単結晶の成長は、所望の抵抗値を有するウェハを得るために坩堝１０１内に窒素（Ｎ２）供給量を調整しながら行う。また一般に、作製された炭化珪素インゴットの一部から種結晶を取得し、再度成長させることを繰り返す。この際、アンドープのインゴットを製造する場合にはアンドープの種結晶を用い、窒素ドープのインゴットを製造する場合には窒素ドープの種結晶を用いるのが一般的であった。そして、これまでは窒素濃度の高いｎ型の炭化珪素ウェハを作製する場合、同様に窒素濃度の高い種結晶を用いることが一般的であった。これに対し、本発明は、窒素濃度の低い種結晶を用いて窒素濃度の高いｎ型の炭化珪素インゴット（ひいては炭化珪素ウェハ）を製造することが従来技術と異なる特徴である。
(Seed crystal preparation process)
First, a seed crystal used for producing the silicon carbide single crystal of the present invention is prepared. As shown in FIG. 2A, a silicon carbide seed crystal 20A is attached to a graphite member 102 using a carbon adhesive or the like, and a silicon carbide single crystal 10A is grown on the surface of the silicon carbide seed crystal 20A by a sublimation method. . During silicon carbide single crystal growth in this seed crystal preparation step, growth is performed without supplying nitrogen gas (without nitrogen doping). Normal silicon carbide single crystal is grown while adjusting the supply amount of nitrogen (N 2 ) in the crucible 101 in order to obtain a wafer having a desired resistance value. Also, in general, it is repeated to obtain a seed crystal from a part of the produced silicon carbide ingot and to grow again. Under the present circumstances, it was general to use an undoped seed crystal when manufacturing an undoped ingot, and to use a nitrogen dope seed crystal when manufacturing a nitrogen-doped ingot. In the past, when producing an n-type silicon carbide wafer having a high nitrogen concentration, it has been common to use a seed crystal having a high nitrogen concentration as well. On the other hand, the present invention is different from the prior art in that an n-type silicon carbide ingot (and thus a silicon carbide wafer) having a high nitrogen concentration is manufactured using a seed crystal having a low nitrogen concentration.
得られた炭化珪素単結晶１０Ａのインゴットを黒鉛部材１０２から取り外し、その一部分１０ａを切り出す。切り出した部分１０ａが、本発明の炭化珪素単結晶の製造に用いる炭化珪素種結晶２０Ｂに相当する。 The obtained silicon carbide single crystal 10A ingot is removed from the graphite member 102, and a portion 10a thereof is cut out. Cut-out portion 10a corresponds to silicon carbide seed crystal 20B used for manufacturing the silicon carbide single crystal of the present invention.
炭化珪素種結晶の厚さは１ｍｍ以上がであることが好ましく、２ｍｍ以上であることがより好ましい。種結晶が１ｍｍ未満であると、黒鉛との熱膨張係数差で割れやすく、また、再結晶の際の昇温時に種結晶に結晶欠陥が入る場合があるため、厚くすることが好ましい。上限としては、厚すぎるとコストが高くなるため１０ｍｍ以下が好ましい。 The thickness of the silicon carbide seed crystal is preferably 1 mm or more, and more preferably 2 mm or more. If the seed crystal is less than 1 mm, it is easy to crack due to the difference in thermal expansion coefficient from graphite, and crystal defects may enter the seed crystal at the time of temperature increase during recrystallization. As the upper limit, if it is too thick, the cost increases, and therefore it is preferably 10 mm or less.
炭化珪素種結晶２０Ｂは、窒素ドープが行われておらず、窒素濃度が５×１０１７ｃｍ−３以下に抑えられているため、光の透過率が高く、その一方の側において反対側の状態を目視（透視）できる程度の透明性を有している。特に、炭化珪素種結晶の厚さを１ｍｍ以上とした場合、通常デバイスに使用される基板の窒素濃度である３×１０１８ｃｍ−３以上では、可視光に対して厚さ方向に不透明になってしまうので、窒素濃度を５×１０１７ｃｍ−３以下に抑えて透過率を高くする効果が大きい。 Since silicon carbide seed crystal 20B is not doped with nitrogen and the nitrogen concentration is suppressed to 5 × 10 17 cm −3 or less, the light transmittance is high, and the state on the opposite side on one side is high. Have a degree of transparency that allows them to be viewed visually. In particular, when the thickness of the silicon carbide seed crystal is 1 mm or more, it becomes opaque in the thickness direction to visible light at 3 × 10 18 cm −3 or more, which is the nitrogen concentration of the substrate used for the device. The effect of suppressing the nitrogen concentration to 5 × 10 17 cm −3 or less to increase the transmittance is large.
また、種結晶の窒素濃度は５×１０１７ｃｍ−３以下とすることが好ましく、３×１０１７ｃｍ−３以下とすることがより好ましく、１×１０１７ｃｍ−３以下とすることがさらに好ましい。窒素濃度が低いと、より透明度が増して検査の精度が上がる。特に、基板が厚い場合、窒素濃度が低いことはより有効である。 Further, the nitrogen concentration of the seed crystal is preferably 5 × 10 17 cm −3 or less, more preferably 3 × 10 17 cm −3 or less, and further preferably 1 × 10 17 cm −3 or less. preferable. The lower the nitrogen concentration, the more transparent and the more accurate the inspection. In particular, when the substrate is thick, low nitrogen concentration is more effective.
尚、前記の種結晶準備工程では、窒素ガスを供給せずに成長を行う方法を示したが、原料が高純度であってアンドープで高純度の炭化珪素単結晶が得られる場合には、窒素濃度を５×１０１７ｃｍ−３以下とする範囲で、窒素ガスを微小量供給してもよい。 In the above-mentioned seed crystal preparation step, although the method of growing without supplying nitrogen gas is shown, when the raw material is high purity and silicon carbide single crystal with high purity is obtained, nitrogen can be obtained. A small amount of nitrogen gas may be supplied in the range of 5 × 10 17 cm −3 or less.
（第１界面検査工程）
次に、この炭化珪素種結晶２０Ｂを用いて、本発明の炭化珪素単結晶の製造を行う。図２（ｂ）に示すように、炭化珪素種結晶２０Ｂを、カーボン接着剤等の用いて黒鉛部材１０２に取り付ける。
(First interface inspection process)
Next, this silicon carbide seed crystal 20B is used to manufacture a silicon carbide single crystal of the present invention. As shown in FIG. 2B, the silicon carbide seed crystal 20B is attached to the graphite member 102 using a carbon adhesive or the like.
続いて、炭化珪素種結晶２０Ｂの透明性を利用して、その単結晶成長面２０ａ側から黒鉛部材との接触面（裏面）２０ｂ側を、目視によって、あるいは所定の観察手段を用いて観察し、黒鉛部材１０２と炭化珪素種結晶２０Ｂとの界面（第１界面）の状態を検査する。ここでの界面の状態の検査とは、炭化珪素種結晶２０Ｂに裏面から伸びる貫通欠陥を発生させるような因子（気泡、異物等）が、黒鉛部材１０２との界面に存在しているかどうかについての検査を意味している。 Subsequently, using the transparency of the silicon carbide seed crystal 20B, the contact surface (back surface) 20b side with the graphite member is observed visually or using a predetermined observation means from the single crystal growth surface 20a side. Then, the state of the interface (first interface) between the graphite member 102 and the silicon carbide seed crystal 20B is inspected. Here, the inspection of the state of the interface refers to whether or not a factor (air bubbles, foreign matter, etc.) causing the silicon carbide seed crystal 20B to generate a penetration defect extending from the back surface exists at the interface with the graphite member 102. Means inspection.
界面状態の検査によって、図２（ｂ）に示すような裏面から伸びる貫通欠陥の発生因子Ｐの存在が検出された場合には、その除去を行う。例えば、界面に気泡が存在している場合には、真空脱泡または加圧脱泡を行って除去する。また、界面に異物が存在している場合には、一旦、炭化珪素種結晶２０Ｂを黒鉛部材１０２から取り外し、炭化珪素種結晶２０Ｂあるいは黒鉛部材１０２に付着している異物を、ピンセット等により除去した上で、再度取り付ける。 When the presence of the penetrating defect generation factor P extending from the back surface as shown in FIG. 2B is detected by the inspection of the interface state, it is removed. For example, if air bubbles are present at the interface, vacuum degassing or pressure degassing is performed to remove them. Further, when there is a foreign substance at the interface, the silicon carbide seed crystal 20B is once removed from the graphite member 102, and the foreign substance adhering to the silicon carbide seed crystal 20B or the graphite member 102 is removed with tweezers or the like. Attach it again.
種結晶裏面からの貫通欠陥の発生因子Ｐの除去作業後、再度、界面の状態を検査する。気泡や異物等の裏面から伸びる貫通欠陥の発生因子Ｐが、目視あるいは所定の観察手段で検出されなくなる程度、あるいは所定の判断基準以下の面密度となるまで、当該除去作業および検査作業を繰り返す。目視で気泡や異物が完全に見られない状態とすることが好ましい。 After removing the penetration factor generating factor P from the back surface of the seed crystal, the interface state is inspected again. The removal operation and the inspection operation are repeated until the generation factor P of the penetrating defect extending from the back surface such as a bubble or a foreign substance is not detected visually or by a predetermined observation means, or the surface density is equal to or less than a predetermined determination standard. It is preferable that air bubbles and foreign matters are not completely seen with the naked eye.
（単結晶成長工程）
次に、第１界面検査工程を経て、黒鉛部材１０２との界面に裏面から伸びる貫通欠陥の発生因子Ｐが低減された状態で、昇華法により、炭化珪素原料の昇華ガスおよび窒素ガスを供給し、図２（ｃ）に示すように、炭化珪素種結晶２０Ｂの表面に炭化珪素の単結晶１０Ｂを成長させる。窒素ガスの供給は、成長中の炭化珪素単結晶１０Ｂに、窒素が３×１０１８ｃｍ−３以上の濃度でドープされるように、調整して行う。この結果、炭化珪素単結晶１０Ｂ中の窒素濃度は、炭化珪素種結晶２０Ｂ中の窒素濃度の６倍以上となる。
(Single crystal growth process)
Next, through the first interface inspection step, sublimation gas and nitrogen gas of a silicon carbide raw material are supplied by a sublimation method in a state in which the generation factor P of penetration defects extending from the back surface to the interface with the graphite member 102 is reduced. As shown in FIG. 2C, a single crystal of silicon carbide 10B is grown on the surface of the silicon carbide seed crystal 20B. The supply of the nitrogen gas is performed by adjusting so that the silicon carbide single crystal 10B being grown is doped with nitrogen at a concentration of 3 × 10 18 cm −3 or more. As a result, the nitrogen concentration in silicon carbide single crystal 10B is at least six times the nitrogen concentration in silicon carbide seed crystal 20B.
単結晶成長工程での窒素濃度は３×１０１８ｃｍ−３以上とすることが好ましく、５×１０１８ｃｍ−３以上とすることがより好ましい。炭化珪素単結晶の窒素濃度が高いと、キャリア濃度が増加し、デバイスにした時の基板の抵抗を低くすることができる。 The nitrogen concentration in the single crystal growth step is preferably 3 × 10 18 cm −3 or more, and more preferably 5 × 10 18 cm −3 or more. When the nitrogen concentration of the silicon carbide single crystal is high, the carrier concentration is increased, and the resistance of the substrate when formed into a device can be lowered.
最後に、図２（ｄ）に示すように、成長した炭化珪素単結晶１０Ｂのインゴットを、炭化珪素種結晶２０Ｂとともに黒鉛部材１０２から取り外す。 Finally, as shown in FIG. 2D, the grown ingot of silicon carbide single crystal 10B is removed from graphite member 102 together with silicon carbide seed crystal 20B.
なお、炭化珪素単結晶１０Ｂの成長中に、窒素ガスの供給を一時的に止めるか、窒素ガスの供給量を一時的に減らすことによって、成長後の炭化珪素単結晶１０Ｂのインゴットに、窒素濃度が５×１０１７ｃｍ−３以下の低ドープ領域が設けられることになる。低ドープ領域以外の領域は、デバイス動作に必要な濃度（通常は３×１０１８ｃｍ−３以上）となる。低ドープ領域を設ける位置は、窒素ガスの供給を止めるタイミング、あるいは窒素ガスの供給量を減らすタイミングによって調整することができる。 During the growth of the silicon carbide single crystal 10B, the nitrogen concentration is added to the ingot of the grown silicon carbide single crystal 10B by temporarily stopping the supply of nitrogen gas or temporarily reducing the supply amount of the nitrogen gas. A lightly doped region of 5 × 10 17 cm −3 or less is provided. The region other than the low doped region has a concentration (usually 3 × 10 18 cm −3 or more) necessary for device operation. The position where the low doped region is provided can be adjusted by the timing at which the nitrogen gas supply is stopped or the timing at which the nitrogen gas supply amount is reduced.
低ドープ領域の部分は透明性を有しているため、インゴットから切り出すことによって、別の炭化珪素単結晶を成長させる際に、第１界面検査工程を実施するための炭化珪素種結晶として利用することができる。 Since the portion of the lightly doped region has transparency, it is used as a silicon carbide seed crystal for performing the first interface inspection step when another silicon carbide single crystal is grown by cutting out from the ingot. be able to.
上記のように低ドープ領域を設ける場合、他の領域（高ドープ領域）との境界部分において窒素濃度が連続的に変化するように、すなわち低ドープ領域から高ドープ領域に向けて窒素濃度が徐々に増加するように、窒素ガスの供給量を調整してもよい。このようにして、低ドープ領域と高ドープ領域との間での窒素濃度の変化を小さくすることにより、２つの領域の格子定数差に起因する転位等の欠陥の発生を抑制することができる。 When the low-doped region is provided as described above, the nitrogen concentration gradually changes from the low-doped region to the high-doped region so that the nitrogen concentration continuously changes at the boundary portion with the other region (high-doped region). The supply amount of nitrogen gas may be adjusted so as to increase. In this way, by reducing the change in nitrogen concentration between the lightly doped region and the highly doped region, it is possible to suppress the occurrence of defects such as dislocations due to the lattice constant difference between the two regions.
上記単結晶成長工程を経ることによって、本発明の炭化珪素単結晶１０Ｂのインゴットを得ることができるが、この工程の後に、さらに次に述べる界面検査を行ってもよい。 Through the single crystal growth step, an ingot of the silicon carbide single crystal 10B of the present invention can be obtained. After this step, the following interface inspection may be performed.
（第２界面検査工程）
図２（ｄ）に示す状態で、炭化珪素種結晶２０Ｂの透明性を利用して、炭化珪素種結晶２０Ｂの裏面２０ｂ側から単結晶成長面２０ａ側を、目視によって、あるいは所定の観察手段を用いて観察し、炭化珪素単結晶１０Ｂの成長界面（第２界面）の状態を検査する。ここでの成長界面の状態の検査とは、転位密集部や異種多形等による欠陥が、炭化珪素単結晶１０Ｂの成長界面に存在しているかどうかについての検査を意味している。
(2nd interface inspection process)
In the state shown in FIG. 2D, by utilizing the transparency of the silicon carbide seed crystal 20B, the single crystal growth surface 20a side from the back surface 20b side of the silicon carbide seed crystal 20B is visually observed or a predetermined observation means is used. The state of the growth interface (second interface) of the silicon carbide single crystal 10B is inspected by using and observing. Here, the inspection of the state of the growth interface means an inspection as to whether defects due to dislocation crowding or heteropolymorphism exist at the growth interface of silicon carbide single crystal 10B.
第１界面検査工程を経ているため、この工程で見つかる転位や欠陥は、少なくとも、炭化珪素種結晶２０Ｂと黒鉛部材１０Ｂとの界面の状態に起因した、裏面から伸びる貫通欠陥によるものではないことが分かっている。したがって、当該転位、欠陥は、炭化珪素種結晶２０Ｂの表面の形状や、坩堝１０１内における単結晶成長条件、例えば昇華ガスの分布や温度分布等の条件に起因するものと考えられ、これらの改善に絞って対策を立てることができる。 Since the first interface inspection process has been performed, the dislocations and defects found in this process are not at least due to penetration defects extending from the back surface, which are caused by the state of the interface between silicon carbide seed crystal 20B and graphite member 10B. I know. Therefore, the dislocations and defects are considered to be caused by the surface shape of the silicon carbide seed crystal 20B and the single crystal growth conditions in the crucible 101, for example, the conditions such as the distribution of sublimation gas and the temperature distribution. Measures can be made focusing on
以上のように、本実施形態において炭化珪素単結晶の成長に用いる種結晶は、窒素濃度が５×１０１７ｃｍ−３以下に抑えられているため、その一方の側において反対側の状態を目視できる程度に透明な状態である。したがって、種結晶を黒鉛部材に取付けた時点で、種結晶の裏側を目視し、種結晶と黒鉛部材との界面の状態、具体的には、そこに種結晶裏面から伸びる貫通欠陥の発生因子である気泡や異物等が存在しているかどうかを、検査することができる。 As described above, since the nitrogen concentration of the seed crystal used for growing the silicon carbide single crystal in the present embodiment is suppressed to 5 × 10 17 cm −3 or less, the state on the opposite side is visually observed on one side thereof. It is in a state of transparency as much as possible. Therefore, when the seed crystal is attached to the graphite member, the back side of the seed crystal is visually observed, and the state of the interface between the seed crystal and the graphite member, specifically, the generation factor of penetration defects extending from the back surface of the seed crystal there. Whether or not certain air bubbles, foreign matter, etc. are present can be inspected.
検査の結果、気泡が存在している場合には真空脱泡または加圧脱泡を行って除去し、異物が存在している場合には、一度接着面を剥がして異物をピンセット等を用いて除去することにより、黒鉛部材との界面に気泡や異物がない状態で、種結晶上に炭化珪素単結晶を成長させることが可能となる。このようにして、種結晶裏面からの貫通欠陥の発生因子を、製造プロセスの早い段階で発見して除去することにより、種結晶裏面から伸長する貫通欠陥に起因した、基底面転位の発生の問題を回避することができ、最終製品として高品質のＳｉＣデバイスを得ることができる。 If air bubbles are present as a result of the inspection, vacuum defoaming or pressure defoaming is performed to remove them. If foreign matter is present, the adhesive surface is peeled off once and the foreign matter is removed using tweezers. By removing the silicon carbide single crystal, it is possible to grow the silicon carbide single crystal on the seed crystal in a state where there are no bubbles or foreign matters at the interface with the graphite member. Thus, the problem of generation of basal plane dislocation caused by the penetration defect extending from the back surface of the seed crystal by finding and removing the generation factor of the penetration defect from the back surface of the seed crystal at an early stage of the manufacturing process Can be avoided, and a high-quality SiC device can be obtained as a final product.
本発明は、昇華法によってＳｉＣ単結晶を成長させる際に活用することができ、ＳｉＣ単結晶を用いたデバイスの特性に影響を及ぼすキラー欠陥を低減し、歩留りの向上に大きく貢献する手段を提供するものである。 The present invention can be utilized when growing a SiC single crystal by a sublimation method, and provides a means that greatly reduces killer defects that affect the characteristics of a device using a SiC single crystal and significantly improves yield. To do.
１００・・・炭化珪素単結晶の製造装置
１０１・・・坩堝
１０２・・・黒鉛部材
１０３・・・コイル
１０４・・・テーパーガイド
１０５・・・インゴットの周辺部分
１０、１０Ａ、１０Ｂ、４０・・・炭化珪素単結晶
１０ａ・・・炭化珪素単結晶の一部分
２０、２０Ａ、２０Ｂ、５０・・・炭化珪素種結晶
２０ａ・・・炭化珪素種結晶の単結晶成長面
２０ｂ、５０ｂ・・・炭化珪素種結晶の裏面
３０・・・原料
Ｄ・・・種結晶裏面から伸びる貫通欠陥
Ｐ・・・種結晶裏面から伸びる貫通欠陥の発生因子
100 ... manufacturing apparatus 101 for silicon carbide single crystal ... ... 102 ... ... graphite member 103 ... coil 104 ... taper guide 105 ... peripheral portion 10, 10A, 10B, 40 ...・ Silicon carbide single crystal 10a... Part of silicon carbide single crystal 20, 20A, 20B, 50... Silicon carbide seed crystal 20a... Single crystal growth surface 20b, 50b of silicon carbide seed crystal. Back surface 30 of seed crystal ... Raw material D ... Penetration defect P extending from the back surface of the seed crystal ... Generation factor of penetration defect extending from the back surface of the seed crystal
Claims (7)
坩堝内の黒鉛部材に、窒素濃度を５×１０１７ｃｍ−３以下に抑えた炭化珪素種結晶を取り付け、前記黒鉛部材と前記炭化珪素種結晶との界面の状態を検査する第１界面検査工程と、
炭化珪素原料の昇華ガスおよび窒素ガスを供給し、３×１０１８ｃｍ−３以上の濃度で窒素ドープされた、炭化珪素単結晶を成長させる単結晶成長工程と、を順に有することを特徴とする炭化珪素単結晶の製造方法。 A method of producing a silicon carbide single crystal by a sublimation method,
A first interface inspection step of attaching a silicon carbide seed crystal whose nitrogen concentration is suppressed to 5 × 10 17 cm −3 or less to a graphite member in a crucible and inspecting the state of the interface between the graphite member and the silicon carbide seed crystal When,
And supplying a sublimation gas of a silicon carbide raw material and a nitrogen gas, and sequentially growing a single crystal growing step of growing a silicon carbide single crystal which is doped with nitrogen at a concentration of 3 × 10 18 cm −3 or more. Method for producing silicon carbide single crystal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018009990A JP7109197B2 (en) | 2018-01-24 | 2018-01-24 | Silicon carbide single crystal manufacturing method, silicon carbide single crystal ingot |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018009990A JP7109197B2 (en) | 2018-01-24 | 2018-01-24 | Silicon carbide single crystal manufacturing method, silicon carbide single crystal ingot |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2019127416A true JP2019127416A (en) | 2019-08-01 |
| JP7109197B2 JP7109197B2 (en) | 2022-07-29 |
Family
ID=67471846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018009990A Active JP7109197B2 (en) | 2018-01-24 | 2018-01-24 | Silicon carbide single crystal manufacturing method, silicon carbide single crystal ingot |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7109197B2 (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003104799A (en) * | 2001-09-28 | 2003-04-09 | Nippon Steel Corp | Silicon carbide single crystal ingot and its manufacturing method |
| JP2015098420A (en) * | 2013-11-20 | 2015-05-28 | 住友電気工業株式会社 | Silicon carbide ingot and production method of silicon carbide substrate |
-
2018
- 2018-01-24 JP JP2018009990A patent/JP7109197B2/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003104799A (en) * | 2001-09-28 | 2003-04-09 | Nippon Steel Corp | Silicon carbide single crystal ingot and its manufacturing method |
| JP2015098420A (en) * | 2013-11-20 | 2015-05-28 | 住友電気工業株式会社 | Silicon carbide ingot and production method of silicon carbide substrate |
Also Published As
| Publication number | Publication date |
|---|---|
| JP7109197B2 (en) | 2022-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI408262B (en) | Epitaxial sic single crystal substrate and method for manufacturing epitaxial sic single crystal substrate | |
| JP6619874B2 (en) | Polycrystalline SiC substrate and manufacturing method thereof | |
| KR100913636B1 (en) | Silicon single crystal manufacturing method and silicon wafer manufacturing method | |
| JP2008115050A (en) | Method for producing epitaxial wafer | |
| US20160233080A1 (en) | Silicon carbide semiconductor substrate and method for manufacturing same | |
| JP6120742B2 (en) | Method for manufacturing single crystal ingot, method for manufacturing single crystal substrate, and method for manufacturing semiconductor device | |
| KR101313462B1 (en) | Method for heat treating silicon wafer | |
| JP2010001210A (en) | Epitaxially coated silicon wafer having <110> orientation and method for producing the same | |
| CN110268106B (en) | SiC wafer and method for producing SiC wafer | |
| WO2019244580A1 (en) | Device for growing silicon carbide single crystal and method for producing silicon carbide single crystal | |
| US11795576B2 (en) | Production method of silicon carbide wafer, production method of semiconductor substrate, and production method of silicon carbide semiconductor device | |
| US10985042B2 (en) | SiC substrate, SiC epitaxial wafer, and method of manufacturing the same | |
| CN115427615A (en) | Silicon carbide single crystal and method for producing silicon carbide single crystal | |
| KR101473787B1 (en) | Method for pulling silicon single crystal | |
| JP2019127416A (en) | Production method of silicon carbide single crystal and silicon carbide single crystal ingot | |
| KR20080076792A (en) | Silicon wafer and its manufacturing method | |
| JP5463693B2 (en) | Manufacturing method of silicon epitaxial wafer | |
| JP2005132703A (en) | Method for manufacturing silicon carbide substrate, and silicon carbide substrate | |
| JP2004165489A (en) | Epitaxial silicon wafer, its manufacturing method and semiconductor device | |
| US20220028688A1 (en) | Method of manufacturing silicon carbide epitaxial wafer | |
| JP2003068744A (en) | Silicon wafer manufacturing method, silicon wafer, and soi wafer | |
| JP2005223092A (en) | Manufacturing method of epitaxial silicon wafer, and silicon wafer manufactured thereby | |
| KR20190100653A (en) | Method for correcting shape of silicon single crystal ingot | |
| JP2011134830A (en) | Epitaxial wafer | |
| JP7331520B2 (en) | Epitaxial silicon wafer manufacturing method, epitaxial silicon wafer, silicon wafer manufacturing method, and semiconductor device manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20180222 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20200824 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20210430 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20210511 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20210712 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20210910 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20220201 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20220404 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20220621 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20220719 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7109197 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313115 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |