Microstructure and Physical Properties of Magnetic Particles Embedded in Semiconductor AIN Films Having Highly Thermal Conductivity

本研究的目的是利用低成本的制备设备制备含有磁性颗粒（如Co， Fe和Fe-Co合金）的纳米复合AlN薄膜，并研究其微观结构和相关物理性能。氮化铝是一种具有高导热性和高耐化学性的半导体。主要研究结果如下：(1)在双靶直流溅射室中，通过改变氩气与氮气的组成比，可以制备出含有一定量Go、Fe和Fe- co粒子的AlN薄膜。对退火膜和沉积膜的微观结构和电阻率等磁性能进行了详细的研究，并对两者的特点进行了比较。(2)当氮气与氩气的气体比较大时，沉积的薄膜比小气体比下制备的薄膜更具无定形，且…more在退火过程中表现出不同的结晶行为。在较高气体比条件下制备的沉积AlN薄膜完全不呈现柱状结构。(3)在较低气体比下使用Al-Co复合靶材时，也未观察到膜中CoNx的形成。当使用Al-Fe靶材时，沉积膜不表现出任何磁性。这可能是由于制备了一种新形成的不具有磁性的AlFe化合物。而氮化铁则是经过退火和高温分解后形成的。对于退火后的两种薄膜，我们可以观察到磁性能和电阻率的剧烈变化，这是由于薄膜的微观结构发生了变化。(4) Al靶和FeCo靶均用于纳米复合膜的形成，大部分薄膜在400℃左右从衬底上起球。C，这是由于用FeCo靶制备的薄膜分解成Co相和FeN相的过程比较剧烈。(5)对Co-C薄膜的动态硬度进行了初步的基础研究，发现DHT115的测定可用于估计薄膜中的金属成分。这一结果表明，该方法在对Co-C薄膜的结果进行改进后，将能够估计含磁性颗粒的AlN薄膜的金属成分。少

The purpose of this study is to fabricate nanocomposite AlN films containing magnetic particles, such as Co, Fe, and Fe-Co alloys by the use of a low-cost preparation apparatus, and to examine their microstructure and relevant physical properties. AlN is a semiconductor which has highly thermal conductivity and highly chemical resistance. The main results are as follows : (1) By changing the composition ratio of argon gas to nitrogen gas as sputtering gas in a two-facing-target dc sputtering chamber, it was easy to fabricate AlN films which contain Go, Fe, and Fe-Co particles in a desired range of composition. Their microstructure and magnetic properties including electrical resistivity were examined for the annealed films as well as as-deposited films in detail, and their characteristics were summarized in comparison with each other. (2) When the gas ratio of nitrogent to argon is large, as-depsosited films appear more amorphous-like than the films prepared at the small gas ratio, and … More showed different behavior of crystalization during annealing. As-deposite AlN films do not exhibit collumnar structure at all for the films prepared at higher gas ratios. (3) The formation of CoNx was not seen for the films even when the Al-Co comosite targets were used at lower gas ratios. When Al-Fe target was used, as-deposited films did not show any magnetic properties. This may be ascribed to the fabrication of a newly formed AlFe compound which does not exhibit magnetic property. But FeNx iron-nitrides were formed after annealing and decomposed at elevated temperatures. For both films after annealing, we can observe a drastic change in magnetic property as well as electrical resistivity, and this was ascribed to the changes in microstructure in the films. (4) Both Al target and FeCo target were used for the formation of nanocomposite films, and most of the films were pilled out from the substrates at around 400 。C, and this was ascribe to the decomposition process of the films into Co phase and FeN phase which took place drastically for the films prepared by using FeCo target. (5) A fundamental study concerning the measurement of dynamic hardness was performed preliminarily for the Co-C films, It was found that the measurements of DHT115 are available for estimation of metal composition in the films. This result suggests that this method will be able to estimate the metal composition of AlN films containing magnetic particles after some improvements according to the previous results for the Co-C films. Less