Realization of High-Reliable Thin Film Capacitor by Anodizing A1- Transition Metal Intermetallic Compounds

通常，许多化学计量的金属间化合物在高温下表现出高硬度和高热稳定性。然后，可以预期，通过阳极氧化由能够阳极氧化的阀金属组成的化学计量和低电阻的金属间化合物，可以实现具有高耐热性能和低损耗性能的薄膜电容器。此外，如果对Al和Hf、Zr和Ta组成的金属间化合物进行阳极氧化，由于Hf、Zr和Ta氧化物的介电常数相对较大，我们预期可以实现高介电常数电容器。因此，我们采用共溅射法制备了Al_3Hf、Al_3Zr和Al_3Ta金属间化合物薄膜，并对这些阳极氧化电容器的电容性能、漏电流和耐热性能进行了测试。获得了以下结果。(1)该阳极氧化电容器的耐热性能上级目前广泛使用的钽阳极氧化电容器。(2)其中Al_3Ta电容器的介电常数最高。（3）Al_3Hf电容器的耐热性能最好，而Al_3Zr电容器的初始电容性能最好。(4)这三种阳极氧化膜电容器的漏电流没有明显的极性差异，因此，铝-过渡金属间化合物阳极氧化膜电容器是实现高可靠性薄膜电容器的最有前途的方法之一。

Generally, many stoichiometric intermetallic compounds exhibit high hardeness and high thermal stability at high temperatures. It is then expected that thin film capacitors with high heat-proof properties and low loss properties can be realized by anodizing stoichiometric and low-resistive intermetallic compounds composed of valve metals which are able to anodize. In addition, if intermetallic compounds which are composed of Al and Hf, Zr and Ta are anodized, we expect that high permitivity capacitor can be realized because the dielectric constans of Hf, Zr and Ta oxides are relatively large. Therefore, we prepared the intermetallic compound films of Al_3Hf, Al_3Zr and Al_3Ta by co-sputtering method, and examined the capacitor properties, leakage current and the heat-proof properties of these anodized capacitors. Following results were obtained.(1) The heat-proof properties of these anodized capacitors were superior to that of Ta anodized capacitor which has been widely used to date. (2) The dielectric constant of Al_3Ta capacitor among these capacitors was the highest. (3)The best heat-proof property could be obtained by using Al_3Hf capacitor, while the initial capacitor properties of Al_3Zr was the best. (4) The difference of the polarity on the leakage current was not recognized in these three anodized capacitors.Therefore, it is concluded that the thin film capacitors prepared by anodizing Al-transition metal intermetallic compounds are one of the most promising mothods to realize high reliable thin film capacitors.