KR100471405B1 - Method forming gate dielectric in semiconductor device - Google Patents
Method forming gate dielectric in semiconductor device Download PDFInfo
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- KR100471405B1 KR100471405B1 KR10-2000-0036829A KR20000036829A KR100471405B1 KR 100471405 B1 KR100471405 B1 KR 100471405B1 KR 20000036829 A KR20000036829 A KR 20000036829A KR 100471405 B1 KR100471405 B1 KR 100471405B1
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- Prior art keywords
- oxygen
- oxide film
- semiconductor device
- gate insulating
- forming
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- 238000000034 method Methods 0.000 title claims abstract description 13
- 239000004065 semiconductor Substances 0.000 title claims abstract description 12
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 18
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000001301 oxygen Substances 0.000 claims abstract description 17
- 229910017840 NH 3 Inorganic materials 0.000 claims abstract description 11
- 239000006227 byproduct Substances 0.000 claims abstract description 9
- 238000006243 chemical reaction Methods 0.000 claims abstract description 8
- 239000000758 substrate Substances 0.000 claims abstract description 8
- 238000005121 nitriding Methods 0.000 claims description 3
- 229910052757 nitrogen Inorganic materials 0.000 claims description 3
- 240000007429 Tor tor Species 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 150000002829 nitrogen Chemical class 0.000 abstract description 7
- TUJKJAMUKRIRHC-UHFFFAOYSA-N hydroxyl Chemical compound [OH] TUJKJAMUKRIRHC-UHFFFAOYSA-N 0.000 abstract description 3
- 150000002926 oxygen Chemical class 0.000 description 8
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 4
- 229910052796 boron Inorganic materials 0.000 description 4
- 230000035515 penetration Effects 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical group [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000005468 ion implantation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 1
- 229920005591 polysilicon Polymers 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/43—Electrodes ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/49—Metal-insulator-semiconductor electrodes, e.g. gates of MOSFET
- H01L29/51—Insulating materials associated therewith
- H01L29/518—Insulating materials associated therewith the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/02104—Forming layers
- H01L21/02107—Forming insulating materials on a substrate
- H01L21/02225—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer
- H01L21/02227—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process
- H01L21/02249—Forming insulating materials on a substrate characterised by the process for the formation of the insulating layer formation by a process other than a deposition process formation by combined oxidation and nitridation performed simultaneously
Abstract
본 발명은 고신뢰성을 갖는 게이트절연막의 형성 방법에 관한 것으로, 이를 위한 본 발명은 산소(O2)와 NH3의 반응에 의해 생성된 부산물 중 활성화산소(O)와 하이드록실라디칼(OH)을 이용하여 반도체기판상에 산화막을 성장시킴과 동시에 상기 부산물 중 NO와 활성화질소(N)를 이용하여 상기 성장되는 산화막을 질화시킨다.The present invention relates to a method of forming a gate insulating film having a high reliability, the present invention for the active by-products generated by the reaction of oxygen (O 2 ) and NH 3 and the active oxygen (O) and hydroxyl radical (OH) The oxide film is grown on the semiconductor substrate using the NO and activated nitrogen (N) in the by-products and the nitrided oxide film is nitrided.
Description
본 발명은 반도체소자의 제조 방법에 관한 것으로, 특히 신뢰성이 높은 게이트산화막의 형성 방법에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for forming a highly reliable gate oxide film.
일반적으로 반도체소자의 DRAM 및 로직의 게이트산화막으로 열(Thermally) 또는 급속열처리(Rapid thermally)에 의해 성장된 SiO2를 사용하고 있다.In general, SiO 2 grown by thermal or Rapid thermally is used as a gate oxide film of DRAM and logic of a semiconductor device.
최근에, 고신뢰성을 갖는 게이트산화막을 형성하는 방법으로, 도 1에 도시된 바와 같이, 낮은 압력에서 산소(O2)와 수소(H2)를 반응시키면, 부산물로서 활성화 산소(Atomic oxgen)와 하이드록실라디칼(Hydroxyl radical; OH)이 생성데는데, 이러한 활성화 산소에 의해 반도체기판(11) 표면에 성장된 게이트산화막(12)은 일반적인 O2 게이트산화막이나 습식산화막(H2O oxide)에 비해 신뢰성이 크게 증가한다.Recently, as a method of forming a gate oxide film having high reliability, as shown in FIG. 1, when oxygen (O 2 ) and hydrogen (H 2 ) are reacted at a low pressure, activated oxygen (Atomic oxgen) and Hydroxyl radical (OH) is produced, and the gate oxide film 12 grown on the surface of the semiconductor substrate 11 by such activated oxygen is compared with a general O 2 gate oxide film or a wet oxide film (H 2 O oxide). The reliability is greatly increased.
그러나, 이러한 종래기술은 핫캐리어주입(Hot carrier ingection)에 대해 신뢰성 증가 및 보론 침투(Boron penetration)에 대한 억제 특성을 증가시키기 위해 N2O 나 NO 분위기에서 후속 열처리를 해야되기 때문에 공정이 복잡해지고 써멀버짓 (Thermal budget)이 증가하는 문제점이 있다.However, this prior art is complicated by the subsequent heat treatment in N 2 O or NO atmosphere in order to increase the reliability of the hot carrier ingection and increase the suppression against boron penetration. There is a problem that thermal budget increases.
본 발명은 상기 종래기술의 문제점을 해결하기 위해 안출한 것으로서, 핫캐리어신뢰성을 증가시키고 보론 침투을 억제시키는데 적합한 게이트산화막의 형성 방법을 제공함에 그 목적이 있다. The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a method of forming a gate oxide film suitable for increasing hot carrier reliability and suppressing boron penetration.
상기의 목적을 달성하기 위한 본 발명의 게이트절연막 형성 방법은 산소(O2)와 NH3의 반응에 의해 생성된 부산물 중 활성화산소(O)와 하이드록실라디칼(OH)을 이용하여 반도체기판상에 산화막을 성장시킴과 동시에 상기 부산물 중 NO와 활성화질소(N)를 이용하여 상기 성장되는 산화막을 질화시키는 것을 특징으로 한다.The gate insulating film forming method of the present invention for achieving the above object is on the semiconductor substrate by using the active oxygen (O) and hydroxyl radical (OH) in the by-product generated by the reaction of oxygen (O 2 ) and NH 3 . The oxide film is grown, and the oxide film is nitrided using NO and activated nitrogen (N).
이하, 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자가 본 발명의 기술적 사상을 용이하게 실시할 수 있을 정도로 상세히 설명하기 위하여, 본 발명의 가장 바람직한 실시예를 첨부 도면을 참조하여 설명하기로 한다.Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. .
도 2a 내지 도 2b는 본 발명의 실시예에 따른 게이트절연막의 형성 방법을 도시한 도면이다.2A to 2B illustrate a method of forming a gate insulating film according to an exemplary embodiment of the present invention.
도 2a에 도시된 바와 같이, 반도체기판(21)에 소자간 격리를 위한 필드산화막(22)을 형성한 후, HF의 산화막식각용액에 의해 문턱전압 이온주입을 위한 스크린 산화막이나 희생산화막을 제거하여 활성영역을 노출시킨다.As shown in FIG. 2A, after forming the field oxide film 22 for isolation between devices on the semiconductor substrate 21, the screen oxide film or the sacrificial oxide film for threshold voltage ion implantation is removed by the oxide film etching solution of HF. Expose the active area.
도 2b에 도시된 바와 같이, 활성영역이 노출된 반도체기판(21)을 챔버 (Chamber)에 로딩(Loading)한 후, 챔버내에서 산소(O2)와 NH3 를 동시에 흘려준다. 이어, 상기 산소(O2)와 NH3의 반응에 의한 부산물인 활성화 산소(Atomic Oxigen) 및 NO를 이용하여 상기 활성영역의 표면을 산화시킨다.As shown in FIG. 2B, after loading the semiconductor substrate 21 in which the active region is exposed to the chamber, oxygen (O 2 ) and NH 3 are simultaneously flown in the chamber. Subsequently, the surface of the active region is oxidized using Atomic Oxigen and NO which are by-products of the reaction of oxygen (O 2 ) and NH 3 .
이 때, 상기 챔버내를 고온상태에서 저압으로 유지하면서 산소와 산소에 대해 상대적으로 적은 양의 NH3가스를 흘리면 산소와 NH3가 반응하면서 다음과 같은 부산물을 생성한다.At this time, while maintaining the inside of the chamber at a high pressure at a low pressure while flowing a relatively small amount of NH 3 gas to oxygen and oxygen, oxygen and NH 3 reacts to produce the following by-products.
상기 화학식1에 나타난 것처럼, 상기 반응을 통해 H2O를 포함하여 활성화산소(O), 하이드록실 라디칼(OH), NO 및 활성화질소(N)가 생성된다.As shown in Formula 1, the reaction generates H 2 O, including activated oxygen (O), hydroxyl radicals (OH), NO and activated nitrogen (N).
여기서, 상기 H2O는 전체 산화속도를 증가시키는 역할을 하며, 활성화 산소 및 하이드록실라디칼은 산화막의 신뢰성을 증가시킨다.Here, the H 2 O serves to increase the overall oxidation rate, the activated oxygen and hydroxyl radicals increase the reliability of the oxide film.
그리고 상기 NO 및 활성화질소는 산화막내에서 확산하여 Si/SiO2의 계면에서 실리콘 댕글링본드(Silicon dangling bond)나 스트레인드 본드(Strained bond) 등에 결합되어 실리콘-질소 본드(Si-N bond)를 형성하여 게이트절연막의 신뢰성을 더욱 증가시키며, 후속 P형 도핑 폴리실리콘게이트전극을 형성할 시 보론의 침투를 억제한다.In addition, the NO and activated nitrogen diffuse in the oxide film and are bonded to a silicon dangling bond or a strained bond at a Si / SiO 2 interface to form a silicon-nitrogen bond. It further increases the reliability of the gate insulating film, and suppresses the penetration of boron when forming a subsequent P-type doped polysilicon gate electrode.
상기한 활성화 산소(O) 및 활성화 질소(N)는 쉽게 다른 원소들과 반응하여 없어지기 때문에 10torr∼100torr의 저압에서 이루어져야 하며, 단일 웨이퍼로 진행되는 챔버에서 이루어져야 한다. 또한, 800℃∼1000℃의 온도에서 진행되며, 상기 활성화산소(O)가 어느 정도 존재하면서 폭발적인 반응을 억제하기 위해 산소에 대한 NH3의 플로우율을 1%∼20%로 조절한다.Since the activated oxygen (O) and the activated nitrogen (N) are easily reacted with other elements and disappeared, the activated oxygen (O) and the activated nitrogen (N) should be made at a low pressure of 10 tortor to 100torr, and should be made in a chamber that progresses to a single wafer. In addition, it proceeds at a temperature of 800 ℃ to 1000 ℃, in order to suppress the explosive reaction while the active oxygen (O) to some extent to adjust the flow rate of NH 3 to oxygen to 1% to 20%.
상기 표면이 산화된 반도체기판(21)은 활성화 질소(N) 및 NO등에 의해 계면에 질소가 결합되어 게이트절연막으로서 옥시나이트라이드(Oxynitride)(23)가 형성되는 것을 도시하고 있다.In the semiconductor substrate 21 having the surface oxidized, nitrogen is bonded to the interface by activating nitrogen (N), NO, and the like to form oxynitride 23 as a gate insulating film.
상술한 바와 같이, 활성화산소 및 하이드록실라디칼을 이용하면서 동시에 게이트절연막을 질화시키면, 70Å이하의 두께를 가지는 고신뢰성의 게이트절연막을 얻을 수 있다.As described above, when the gate insulating film is nitrided at the same time using activated oxygen and hydroxyl radicals, a highly reliable gate insulating film having a thickness of 70 kPa or less can be obtained.
도면에 도시되지 않았지만, 상기와 같은 산화 및 질화시켜 형성된 게이트절연막은 고신뢰도의 게이트절연막을 요구하는 1G급 DRAM의 고집적소자나 Flash EEPROM의 터널산화막(Tunnel oxide)으로 적용할 수 있다.Although not shown in the drawings, the gate insulating film formed by oxidizing and nitriding as described above may be used as a highly integrated device of a 1G class DRAM or a tunnel oxide film of a flash EEPROM that requires a high reliability gate insulating film.
본 발명의 기술 사상은 상기 바람직한 실시예에 따라 구체적으로 기술되었으나, 상기한 실시예는 그 설명을 위한 것이며 그 제한을 위한 것이 아님을 주의하여야 한다. 또한, 본 발명의 기술 분야의 통상의 전문가라면 본 발명의 기술 사상의 범위 내에서 다양한 실시예가 가능함을 이해할 수 있을 것이다.Although the technical idea of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.
상술한 바와 같은 본 발명의 게이트절연막 형성 방법은 산소와 NH3가스의 반응에 의한 부산물 중 활성화산소를 이용하여 신뢰성이 높은 산화막을 형성할 수 있고, 상기 부산물 중 활성화질소 및 NO을 이용하여 산화막을 질화시키므로써, 핫캐리어 신뢰성을 증가시키고 보론 침투를 억제시킬 수 있는 효과가 있다.In the gate insulating film forming method of the present invention as described above, it is possible to form a highly reliable oxide film using activated oxygen in a by-product of the reaction of oxygen and NH 3 gas, and to form an oxide film using activated nitrogen and NO in the by-product. By nitriding, there is an effect of increasing hot carrier reliability and suppressing boron penetration.
도 1은 종래기술에 따른 게이트절연막의 형성 방법을 개략적으로 도시한 도면,1 is a view schematically showing a method of forming a gate insulating film according to the prior art;
도 2a 내지 도 2b는 본 발명의 실시예에 따른 게이트절연막의 형성 방법을 도시한 도면.2A to 2B illustrate a method of forming a gate insulating film according to an embodiment of the present invention.
*도면의 주요 부분에 대한 부호의 설명* Explanation of symbols for the main parts of the drawings
21 : 반도체기판 22 : 필드산화막21 semiconductor substrate 22 field oxide film
23 : 옥시나이트라이드23: oxynitride
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| US7585729B2 (en) | 2006-10-12 | 2009-09-08 | Samsung Electronics Co., Ltd. | Method of manufacturing a non-volatile memory device |
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| KR19980063857A (en) * | 1996-12-05 | 1998-10-07 | 윌리엄비.켐플러 | Thin silicon nitride or silicon oxynitride gate dielectric formation method |
| JPH1126457A (en) * | 1997-06-27 | 1999-01-29 | Samsung Electron Co Ltd | Formation of silicon oxynitride film of semiconductor device |
| WO2000011708A1 (en) * | 1998-08-19 | 2000-03-02 | Advanced Micro Devices, Inc. | Semiconductor device having oxide-nitride gate insulating layer and method of manufacture thereof |
| KR20000053372A (en) * | 1999-01-06 | 2000-08-25 | 포만 제프리 엘 | Oxynitride gate dielectric and method of forming |
| KR20010064414A (en) * | 1999-12-29 | 2001-07-09 | 박종섭 | Method of forming gate dielectric layer with TaON |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7585729B2 (en) | 2006-10-12 | 2009-09-08 | Samsung Electronics Co., Ltd. | Method of manufacturing a non-volatile memory device |
Also Published As
| Publication number | Publication date |
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| KR20020002605A (en) | 2002-01-10 |
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