JPH02217461A - Production of thin oxide film - Google Patents
Production of thin oxide filmInfo
- Publication number
- JPH02217461A JPH02217461A JP3857189A JP3857189A JPH02217461A JP H02217461 A JPH02217461 A JP H02217461A JP 3857189 A JP3857189 A JP 3857189A JP 3857189 A JP3857189 A JP 3857189A JP H02217461 A JPH02217461 A JP H02217461A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- thin film
- sputtering
- substrate
- target
- 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
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- 239000007789 gas Substances 0.000 claims abstract description 45
- 239000000758 substrate Substances 0.000 claims abstract description 20
- 239000002184 metal Substances 0.000 claims abstract description 10
- 229910052751 metal Inorganic materials 0.000 claims abstract description 10
- 238000005546 reactive sputtering Methods 0.000 claims abstract description 7
- 239000007800 oxidant agent Substances 0.000 claims abstract description 6
- 239000010409 thin film Substances 0.000 claims description 29
- 238000004544 sputter deposition Methods 0.000 claims description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 11
- 238000000151 deposition Methods 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 238000000034 method Methods 0.000 abstract description 7
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 5
- 239000001301 oxygen Substances 0.000 abstract description 3
- 229910052760 oxygen Inorganic materials 0.000 abstract description 3
- 238000002425 crystallisation Methods 0.000 abstract 1
- 230000008025 crystallization Effects 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 239000010408 film Substances 0.000 description 14
- 230000000694 effects Effects 0.000 description 10
- 230000008021 deposition Effects 0.000 description 7
- 238000010897 surface acoustic wave method Methods 0.000 description 5
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000001755 magnetron sputter deposition Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical group [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010574 gas phase reaction Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052987 metal hydride Inorganic materials 0.000 description 1
- 150000004681 metal hydrides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 238000005121 nitriding Methods 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 239000002887 superconductor Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Physical Vapour Deposition (AREA)
Abstract
Description
【発明の詳細な説明】 産業上の利用分野 本発明は酸化物薄膜の製造方法に関する。[Detailed description of the invention] Industrial applications The present invention relates to a method for manufacturing an oxide thin film.
従来の技術
従来、酸化物薄膜のスパッタリングによる堆積技術は酸
化剤としての導入ガスに0□ガスしか用いていなかった
。 例えば、弾性表面波デバイスでカラーTV用映像
中間周波フィルタ等応用されているZnO薄膜では[(
文献)相位 他:応用物理;第50巻 第8号 p58
0−591 (1981)]に示されているように純
02ガス、または、それとArガスとの混合ガスを用い
ている。BACKGROUND OF THE INVENTION Conventionally, sputtering deposition techniques for oxide thin films have used only 0□ gas as an oxidizing agent. For example, in the ZnO thin film used in surface acoustic wave devices such as video intermediate frequency filters for color TVs, [(
Literature) Phase et al.: Applied Physics; Volume 50, No. 8, p58
0-591 (1981)], pure 02 gas or a mixed gas of it and Ar gas is used.
そして、ターゲットはZnOの酸化物ターゲットを用い
ている。A ZnO oxide target is used as the target.
また、N20ガスを用いた反応性スパッタリングは特開
昭81−104087号公報、特開昭63−63153
号公報に示されている。これらは膜の耐候性や基板との
密着性を向上させることを目的にして、非晶質のシリコ
ン酸窒化膜やテルル−セレン−窒素層等の窒化膜を得て
いる。そのために、従来の技術はNeoガスによる窒化
を目的にしたもので、Neoガスを酸化剤として用いて
結晶性等の良い望ましくは窒素を含存しない酸化膜の低
温高速堆積を目的した本発明と異なり、作用と効果とも
異なったものである。In addition, reactive sputtering using N20 gas is disclosed in JP-A-81-104087 and JP-A-63-63153.
It is shown in the publication No. These nitride films, such as amorphous silicon oxynitride films and tellurium-selenium-nitrogen layers, are obtained for the purpose of improving the weather resistance of the film and the adhesion to the substrate. To this end, conventional techniques have aimed at nitriding with Neo gas, whereas the present invention aims at low-temperature, high-speed deposition of an oxide film with good crystallinity, preferably containing no nitrogen, using Neo gas as an oxidizing agent. They are different, and their actions and effects are also different.
さらに、従来5iHaガスとN 20ガスを用いたプラ
ズマCVD法[(文献) A、C,Adams;J、E
lectrochem、soc、、Vol 、128.
1545(1!1181)コでも非晶質の酸化物薄膜の
堆積を行っていた。それは02ガスを用いるとSiH4
ガスとの反応で微粒子が発生しLSI等の故障の原因に
なるのを防止するのを目的としている。そのためNeo
ガスとの反応物が金属水素化物でスパッタによる金属元
素とは異なっており、プラズマ中での気相反応による堆
積であり、堆積した膜中に水素が取り込まれる。Furthermore, conventional plasma CVD method using 5iHa gas and N20 gas [(Reference) A, C, Adams; J, E
lectrochem, soc, Vol. 128.
1545 (1!1181) also deposited an amorphous oxide thin film. It is SiH4 when using 02 gas.
The purpose is to prevent particulates from being generated due to reaction with gas and causing failures in LSIs, etc. Therefore Neo
The reactant with the gas is a metal hydride, which is different from the metal element produced by sputtering, and the deposition is by a gas phase reaction in plasma, and hydrogen is incorporated into the deposited film.
発明が解決しようとする課題
しかしながら、上述の方法では良好な結晶性と配向性を
持ったZnO薄膜を堆積するには基板温度と堆積速度と
の間にスパッタ装置によらない02ガスを用いたことに
よる最適スパッタ条件がある。Problems to be Solved by the Invention However, in the above method, in order to deposit a ZnO thin film with good crystallinity and orientation, it is necessary to use 02 gas between the substrate temperature and the deposition rate, which does not depend on the sputtering equipment. There are optimal sputtering conditions according to
そのため、300℃以下の低温での1μm/h以上の高
速堆積では結晶性と配向性が悪くなり非晶質状態に近ず
き、デバイスへの応用に使用できるZ n 0W11!
f(が得られなかった。また、ZnO薄膜を用いた弾性
表面波フィルターは金属ターゲットを用いた反応性スパ
ッタ法による製造方法では実用化されてない。 本発
明は、この様な問題点を解決し、結晶性等の膜質の良い
酸化物薄膜を低温での高速堆積で得ることを目的として
いる。Therefore, when deposited at a high speed of 1 μm/h or higher at a low temperature of 300° C. or lower, the crystallinity and orientation deteriorate, approaching an amorphous state, and Z n 0W11! can be used for device applications.
f( could not be obtained. Also, surface acoustic wave filters using ZnO thin films have not been put into practical use by manufacturing methods using reactive sputtering methods using metal targets. The present invention solves these problems. The purpose of this method is to obtain oxide thin films with good crystallinity and other properties by high-speed deposition at low temperatures.
課題を解決するための手段
上記問題点を解決するために、本発明では導入ガスに少
なくともN20ガスを用いてスパッタリングを行う。Means for Solving the Problems In order to solve the above problems, in the present invention, sputtering is performed using at least N20 gas as the introduced gas.
作用
上記した手段を用いることによって生ずる本発明の作用
は次のようなものである。酸化剤として導入されたNa
Oガスがスパッタリング時に放電分離されるとき、反応
性に富む原子状酸素を02ガスよりも生成し易く、酸素
分子やそのイオン及び活性種を生成しないと考えられる
。そのため、Zn等の金属との酸化反応が低い基板温度
でも速やかに秩序正しく行われる。Effects The effects of the present invention produced by using the above-mentioned means are as follows. Na introduced as an oxidizing agent
When O gas is discharge separated during sputtering, it is thought that highly reactive atomic oxygen is produced more easily than O2 gas, and oxygen molecules, their ions, and active species are not produced. Therefore, the oxidation reaction with metals such as Zn is quickly and orderly carried out even at low substrate temperatures.
実施例
以下、本発明の実施例について、その製造方法を説明す
る。用いたスパッタリング装置は第1図に示す様な通常
の直流マグネトロンスパッタ装置である。この装置は真
空容器1の内部にターゲット2、マグネット3とシール
ド4より構成される陰極と基板5をとりつけて基板温度
の制御を行う基板ホールダー8より構成される陽極とを
設けている。前記真空容器1にガス導入ロアより導入ガ
スをその流量を調整して導入し、真空排気系でガス圧力
を制御し、高圧電源により前記電極間に直流電圧を印加
することによりスパッタ放電を行うものであ°る。EXAMPLES Hereinafter, the manufacturing method of Examples of the present invention will be explained. The sputtering device used was a normal DC magnetron sputtering device as shown in FIG. This device is provided with a target 2, a cathode made up of a magnet 3 and a shield 4, and an anode made up of a substrate holder 8 to which a substrate 5 is attached and which controls the temperature of the substrate. The gas introduced into the vacuum vessel 1 is introduced from the gas introduction lower by adjusting the flow rate, the gas pressure is controlled by the vacuum exhaust system, and the sputter discharge is performed by applying a DC voltage between the electrodes using a high-voltage power supply. It is.
一例として弾性表面波デバイス等に用いられているZn
O薄膜の堆積方法について述べる。このZn0Mはガラ
ス基板上に結晶性が良くC軸配向した膜が求められてい
る。実験はNeoガスの酸化剤としての効果を顕著に示
すためにターゲット2としてZnの4インチの金属ター
ゲットを用い、基板5上に反応性スパッタリング法によ
り堆積する方法について実施した。基板5−ターゲット
2間距離は40mmである。まず、導入ガスは比較のた
めに本発明のN 20ガスと従来の02ガスの各々を単
独で用いた。導入ガス流1は10800Mで一定にし、
ガス圧力は5mmTorrに保持した。そして、放電電
流300mA、 印加電圧300〜500 V、 基
板温度〜500″Cでスパッタリングを1時間行いガラ
ス基板上にZnO薄膜を堆積した。堆積速度は02ガス
の1.4μm/hに対してN a Oガスでは1.7μ
m/hで堆積速度が向上した。堆積したZnO薄膜の結
晶性と配向性はX線回折で評価した。第2図及び第3図
は(002)のX線回折の半値幅と前記(002)のロ
ッキング曲線の標準偏差角との基板温度依存性を02ガ
スとN 20ガスとを比較した結果を示したものである
。02ガスを用いた場合は結晶性と配向性が基板温度の
低下と共に悪くなり、300℃以下では(110)等の
他の配向も有り混合配向で、結晶性もNIOガスの場合
よりも悪く非晶質状態に近ずいた。As an example, Zn, which is used in surface acoustic wave devices, etc.
A method for depositing an O thin film will be described. A film of this Zn0M with good crystallinity and C-axis orientation is required on a glass substrate. In order to clearly demonstrate the effect of Neo gas as an oxidizing agent, the experiment was conducted using a 4-inch Zn metal target as the target 2 and depositing it on the substrate 5 by reactive sputtering. The distance between the substrate 5 and the target 2 is 40 mm. First, for comparison, the N20 gas of the present invention and the conventional 02 gas were used alone as introduced gases. The introduced gas flow 1 was kept constant at 10800M,
Gas pressure was maintained at 5 mmTorr. Then, sputtering was performed for 1 hour at a discharge current of 300 mA, an applied voltage of 300 to 500 V, and a substrate temperature of ~500''C to deposit a ZnO thin film on the glass substrate. a 1.7μ for O gas
The deposition rate increased by m/h. The crystallinity and orientation of the deposited ZnO thin film were evaluated by X-ray diffraction. Figures 2 and 3 show the results of comparing the substrate temperature dependence of the half-width of X-ray diffraction of (002) and the standard deviation angle of the rocking curve of (002) for 02 gas and N20 gas. It is something that When using 02 gas, the crystallinity and orientation worsen as the substrate temperature decreases, and below 300°C there are other orientations such as (110), resulting in a mixed orientation, and the crystallinity is worse than when using NIO gas. It was close to a crystalline state.
それに対してN 20ガスの場合はほとんど基板温度の
依存性がなく、100℃の低温でも結晶性が良く、配向
性も(002)だけのC軸の単一配向であった。また、
高抵抗で透明な膜が得られたので酸素欠損も少ない。N
20ガスを用いた場合、窒素が膜中に取り込まれる可能
性もあるが、本実施例のZnO膜をオージェ等により組
成分析した結果、窒素は検出限界(約1%)以下であり
膜中に取り込まれておらず、なんら結晶性や電気的特性
に影響を与えていなかった。このことは原子状酸素と金
属元素との反応速度が速いので窒化されなかったのでは
ないかと考えられる。On the other hand, in the case of N 20 gas, there was almost no dependence on the substrate temperature, the crystallinity was good even at a low temperature of 100° C., and the orientation was a single C-axis (002). Also,
Since a transparent film with high resistance was obtained, there were few oxygen vacancies. N
If 20 gas is used, there is a possibility that nitrogen may be incorporated into the film, but as a result of the compositional analysis of the ZnO film of this example by Auger et al. It was not incorporated and had no effect on crystallinity or electrical properties. This is thought to be because the reaction rate between atomic oxygen and the metal element was fast, so nitridation was not achieved.
その結果、NaOガスを用いた事により、′従来ではで
きなかった300℃以下の低温で、しかも1μm、/h
以上の高速堆積でも結晶性等の良好な高品質なZnO膜
が形成できるようになった。そして、そのZnO膜上に
櫛形の金属電極を形成して弾性表面波フィルターとして
の特性を評価した結果、従来のものよりも信号の損失の
少ないものができた。As a result, by using NaO gas, we were able to achieve a temperature of 1 μm/h at a low temperature below 300°C, which was previously impossible.
Even with the above-described high-speed deposition, a high-quality ZnO film with good crystallinity etc. can now be formed. Then, as a result of forming comb-shaped metal electrodes on the ZnO film and evaluating its characteristics as a surface acoustic wave filter, a filter with less signal loss than conventional filters was created.
なお、本発明はN ZnO膜以外の酸化物薄膜の形成
にも適用可能である。Note that the present invention is also applicable to the formation of oxide thin films other than NZnO films.
発明の効果 本発明の効果は次のようなものである。Effect of the invention The effects of the present invention are as follows.
Neoガスを用いてスパッタリングすることにより結晶
性及び配向性の良い酸化物薄膜が低温で高速堆積できた
。その酸化物薄膜は窒素を含存してなく、窒素による悪
影響はなっかた。そして、安価な金属ターゲットを使用
でき、堆積速度の速い反応性スパッタリング法で高品質
な酸化物薄膜が形成できた。さらに、反応性直流スパッ
タリングも可能なので制御の容易な直流電源を使用でき
酸化物薄膜の製造が容易になった。特にZnO薄膜では
金属ターゲットを用いた反応性直流スパッタリングで弾
性表面波フィルター等のデバイス応用できる膜が低温高
速堆積できた。また、本発明の効果は実施例で述べたZ
nO薄膜だけに限らず他の酸化物薄膜(In203等の
透明導電膜、TaO等の絶縁体膜、酸化物高温超電導体
、フェライト等)にも適用できるのは言うまでもない。By sputtering using Neo gas, an oxide thin film with good crystallinity and orientation could be deposited at low temperature and at high speed. The oxide thin film did not contain nitrogen and was not adversely affected by nitrogen. In addition, a high-quality oxide thin film could be formed using a reactive sputtering method that uses an inexpensive metal target and has a high deposition rate. Furthermore, since reactive DC sputtering is also possible, an easily controllable DC power source can be used, making it easier to manufacture oxide thin films. In particular, ZnO thin films, which can be applied to devices such as surface acoustic wave filters, can be deposited at low temperature and at high speed by reactive direct current sputtering using a metal target. Moreover, the effect of the present invention is that Z
Needless to say, the present invention is applicable not only to nO thin films but also to other oxide thin films (transparent conductive films such as In203, insulating films such as TaO, oxide high temperature superconductors, ferrite, etc.).
さらに、ターゲットに酸化物を用いた場合にも同様な効
果があるものと考えられる。Furthermore, it is thought that a similar effect can be obtained when an oxide is used as the target.
以上の効果はN a OガスのみによるものでNOaガ
スや還元性のNoガスでは得られない。さらに、それら
のガスはN 20ガスよりも毒性が強く、高価で蒸気圧
も低いことから製造には適していない。The above effects are due only to N a O gas and cannot be obtained with NOa gas or reducing No gas. Furthermore, these gases are more toxic than N20 gas, expensive, and have low vapor pressure, making them unsuitable for production.
第1図は本発明の実施例で用いた直流マグネトロンスパ
ッタ装置の構成図、第2図は本発明の実施例のZnO薄
膜の(002)のX線回折の半値幅の基板温度依存性を
示す図、第3図は本発明の実施例のZnO薄膜の(OO
2)のX線ロッキングカーブの標準偏差角の基板温度依
存性を示す図である。
2・・・ターゲット、5・・・基板、6・自基板ホール
ダー 8・・・高圧電源。
代理人の氏名 弁理士 粟野重孝 はか工名第1図Fig. 1 is a block diagram of a DC magnetron sputtering apparatus used in an example of the present invention, and Fig. 2 shows the substrate temperature dependence of the half-width of (002) X-ray diffraction of a ZnO thin film in an example of the present invention. Figure 3 shows the ZnO thin film (OO
2) is a diagram showing the dependence of the standard deviation angle of the X-ray rocking curve on the substrate temperature; FIG. 2... Target, 5... Board, 6... Own board holder 8... High voltage power supply. Name of agent: Patent attorney Shigetaka Awano
Claims (5)
ングにて基板上に結晶質の酸化物薄膜を堆積することを
特徴とする酸化物薄膜の製造方法。(1) A method for producing an oxide thin film, which comprises depositing a crystalline oxide thin film on a substrate by sputtering with N_2O gas introduced as an oxidizing agent.
スパッタリングであることを特徴とする特許請求の範囲
第1項記載の酸化物薄膜の製造方法。(2) The method for producing an oxide thin film according to claim 1, wherein the sputtering is reactive sputtering using a metal target.
特許請求の範囲第1項または第2項記載の酸化物薄膜の
製造方法。(3) The method for producing an oxide thin film according to claim 1 or 2, wherein the oxide thin film is a ZnO thin film.
ることを特徴とする特許請求の範囲第1項記載の酸化物
薄膜の製造方法。(4) The method for producing an oxide thin film according to claim 1, wherein the sputtering is reactive direct current sputtering.
する特許請求の範囲第1項または第3項記載の酸化物薄
膜の製造方法。(5) The method for producing an oxide thin film according to claim 1 or 3, wherein the oxide thin film does not contain nitrogen.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1038571A JPH0753902B2 (en) | 1989-02-17 | 1989-02-17 | Method of manufacturing oxide thin film |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1038571A JPH0753902B2 (en) | 1989-02-17 | 1989-02-17 | Method of manufacturing oxide thin film |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH02217461A true JPH02217461A (en) | 1990-08-30 |
JPH0753902B2 JPH0753902B2 (en) | 1995-06-07 |
Family
ID=12528982
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1038571A Expired - Fee Related JPH0753902B2 (en) | 1989-02-17 | 1989-02-17 | Method of manufacturing oxide thin film |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0753902B2 (en) |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01230428A (en) * | 1988-03-10 | 1989-09-13 | Oki Electric Ind Co Ltd | Production of superconducting thin film |
JPH02145761A (en) * | 1988-11-28 | 1990-06-05 | Matsushita Electric Ind Co Ltd | Manufacture of thin superconductor film |
-
1989
- 1989-02-17 JP JP1038571A patent/JPH0753902B2/en not_active Expired - Fee Related
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01230428A (en) * | 1988-03-10 | 1989-09-13 | Oki Electric Ind Co Ltd | Production of superconducting thin film |
JPH02145761A (en) * | 1988-11-28 | 1990-06-05 | Matsushita Electric Ind Co Ltd | Manufacture of thin superconductor film |
Also Published As
Publication number | Publication date |
---|---|
JPH0753902B2 (en) | 1995-06-07 |
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