Study on the control of film properties by low energy ions in sputtering process

溅射过程中低能离子对薄膜性能控制的研究

• 批准号: 08650383
• 负责人: TOMINAGA Kikuo
• 金额: $ 1.54万
• 依托单位: THE UNIVERSITY OF TOKUSHIMA
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650383/
• 关键词: Sputtering; nitride film; oxide film; AlN; ZnO; ITO; transparent conductive film; 酸化亜鉛; 窒化アルミニウム

In this study, for the DC reactive sputtering process for nitrides and oxides, we investigated the influence of ions impinging the substrate on the film properties. Since sputtering system with two faced targets was expected to be effective in decreasing the film bombardment on the substrate by energetic ions, we applied this sytem in investigation of the influence of ion exposure of the substrate. In the film deposition of AlN,the influence of ion bombardment was not decreased even in the facing target sputtering system, and the film growth was degraded by the ion bombardment. The mechanism of acceleration of ions such as nitrogen and argon toward the substrate were cleared to be due to mainly by the potential difference between the plasma potential in discharge region and the floating potential on the substrate. The above influence of ion bombardment on the film was decreased by using alternating sputtering technique where one target was biased at positive potential while another tar … More get was sputtered. The results demonstrated that the ion bombardment can be diminished by this sputtering system, which confirms the ion bombardment is taking an important role in the film quality of AlN film. Setting a mesh in front of the substrate also changed the ion flux bombarding the substrate, which influenced on the residual stress in AlN film. Magnetic field distribution in the facing target sputtering system influenced the ion flux bombarding the substrate. These characteristics were related to the electron and ion flow in the chamber, as a result, the ion flux bombarding the substrate.In the deposition of oxides, we adopted ZnO film and ITO film. We could not obtain the 150-200 mu OMEGAcm resistivity in ZnO (the lowest value reported until now) only by decreasing energetic particles bombarding depositing film. Other factors were more important to acoomplish the lowest value in resistivity. We showed that additional Zn atoms have a strong influence in decreasing the film resistivity. Appropriate addition of Zn atoms improved the film crystallinity, and increased also the carrier concentration and the Hall mobility. This was caused by an increase of nuclei at the first stage in polycrystal film growth. In ITO deposition, we examined the effects of decreasing the energetic oxygen in using facing targets. Certainly we could obtain the lowest film resistivity by this technique. Furthermore, using (00・2) AlN as a substrate we could increase the carrier concentration, but the decrease of Hall mobility was observed. This was due to the increase of donor scattering. As a result, a drastic improvement in resistivity was difficult in ITO film. The improvement of doping efficiency of Sn donors is necessary for much more decrease in ITO film resistivity. Less

在本研究中，对于氮化物和氧化物的直流反应溅射工艺，我们研究了离子撞击衬底对薄膜性能的影响。由于两面靶溅射系统有望有效地减少高能离子对衬底的轰击，因此我们将该系统应用于研究衬底离子暴露的影响。在氮化铝薄膜的沉积过程中，离子轰击的影响即使在对向靶溅射系统中也不会减小，而且离子轰击会降低薄膜的生长速度。结果表明，氮、氩等离子向衬底加速的机理主要是由于放电区的等离子体电位与衬底上的漂移电位之差所致。通过采用交替溅射技术减小了离子轰击对薄膜的上述影响，其中一个靶被偏置在正电位，而另一个靶被偏置到TAR…更多的GET被溅了出来。结果表明，该溅射系统可以减少离子轰击，证实了离子轰击对氮化铝薄膜质量的影响。在衬底前设置网孔也可以改变轰击衬底的离子通量，从而影响AlN薄膜中的残余应力。对向靶溅射系统中的磁场分布影响着离子通量对衬底的轰击。这些特性与电子和离子在腔体中的流动有关，从而导致离子通量轰击衬底。在氧化物的沉积方面，我们采用了氧化锌薄膜和ITO薄膜。仅靠减少高能粒子轰击沉积膜不能获得150-200亩的氧化锌OMEGAcm电阻率(目前报道的最低值)。其他因素对电阻率最低值的补充更为重要。我们发现，添加锌原子对降低薄膜的电阻率有很大的影响。适量的锌原子加入改善了薄膜的结晶度，同时也增加了载流子浓度和霍尔迁移率。这是由于多晶薄膜生长的第一阶段晶核增多所致。在ITO沉积中，我们考察了在使用对向靶时降低高能氧的效果。当然，我们可以通过这种技术获得最低的薄膜电阻率。此外，使用(00·2)AlN作为衬底可以提高载流子浓度，但会降低霍尔迁移率。这是由于施主散射增加所致。因此，ITO薄膜的电阻率很难有大幅度的提高。进一步降低ITO薄膜的电阻率，需要提高锡施主的掺杂效率。较少

项目成果

日下 一也: "交代式スパッタリング法によるAlN膜の残留応力測定" 材料. Vol.46,No.12. 1429-1435 (1997)

Kazuya Kusaka：“通过交替溅射法测量 AlN 膜的残余应力”材料，第 46 卷，第 1429-1435 期。

K.Kusaka: "Effect of External Magnetic Field on Residual Stress in AlN Films Prepared by Sputtering System" Proc.of The Second International Conference on Nitride Semiconductors. Tokushima,Japan. 378 (1997)

K.Kusaka：“外部磁场对溅射系统制备的 AlN 薄膜中残余应力的影响”第二届国际氮化物半导体会议论文集。

Kikuo Tominaga, Takahiro Ao, Ichiro Mori, Kazuya Kusaka and Takao Hanabusa: "Gas Pressure Dependence of AlN Films Prepared in Alternative Magnetron Sputtering" Jpn.J.Appl.Phys.Vol.135. 4972-4975 (1996)

Kikuo Tominaga、Takahiro Ao、Ichiro Mori、Kazuya Kusaka 和 Takao Hanabusa：“替代磁控溅射制备的 AlN 薄膜的气压依赖性”Jpn.J.Appl.Phys.Vol.135。

K.Tominaga: "Transparent Conductive ZnO Film Preparation by Alternative Sputtering of ZnO:Al Target and Either Zn or Al Target" Thin Solid Films. (掲載予定). (1998)

K.Tominaga：“通过 ZnO:Al 靶材和任一 Zn 或 Al 靶材的交替溅射制备透明导电 ZnO 薄膜”（即将出版）。

S.Kumano, N.Umezu, T.Ushiro, T.Moriga, K.Tominaga, and I.Nakabayashi: "Fablication of ZnO Varistor Thin Films by RF Sputtering Technique" Proc.of Int.Conf.on Advanced Materials Development and Performance Evaluation and Application, Auckland, New Zealand,

S.Kumano、N.Umezu、T.Ushiro、T.Moriga、K.Tominaga 和 I.Nakabayashi：“通过射频溅射技术制造 ZnO 压敏电阻薄膜”Proc.of Int.Conf.on Advanced Materials Development and Performance