Properties of group-III nitride semiconductor thin films deposited by RF sputtering.

近年来，在GaN基材料上成功地实现了蓝色LED和LD。III族氮化物是目前新型光电子器件中最有前途的系统。然而，在材料科学和III族氮化物的晶体生长方面仍有许多有待澄清的问题。事实上，就在最近，一些研究人员已经报道了InN的带隙不是通常的1.9 eV，而是可能小于1 eV。因此，通常1.9 eV的带隙能量值得怀疑。在熔融石英玻璃上生长的多晶GaN层具有强光致发光特性。GaN的这种PL特性与传统的III-V半导体如GaAs有很大的不同。同样不寻常的性质预计也会在其他氮化物半导体（如InN）中观察到。本文采用射频反应溅射技术研究了沉积的氮化镓和氮化镓的薄膜性能。结果如下：在室温下观察到非晶GaN: H薄膜的强PL。峰值能值为3.27 eV.2。PL的起源和发光机理尚不清楚。我们认为PL峰来自于几乎无定形薄膜中的小尺寸结晶GaN。InN的带隙能取决于溅射条件。溅射沉积的InN薄膜在带隙能附近的光学性质有待进一步研究。In和Si复合靶反应溅射制备的InN: Si薄膜的晶体、电学和光学性能随Si含量的变化而变化。

Recently, blue LED and LD were successfully achieved in the GaN based materials. The group III nitrides are today the most promising system for new photo-electronics devices. However, many points which must be clarified were remained in the material sciences and crystal growth of the group III nitrides. In fact, very recently, several researchers have reported that the bandgap of InN is not usual 1.9 eV, but may be less than 1 eV. Therefore, the usual band gap energy of 1.9 eV is doubtful. Strong photoluminescence emission (PL) was recently observed for the polycrystalline GaN layer grown on fused silica glass. Such PL property of GaN is quite different from conventional III-V semiconductors like GaAs. The same unusual properties were expected to observe in the other nitride semiconductors like InN. This work was studied about the film properties of the deposited GaN and InN by rf reactive sputtering. The results are follows.1.Strong PL was observed for the amorphous GaN : H films in room temperature. The peak energy value is 3.27 eV.2.The origin and luminescence mechanism of PL are not clear yet. We considered that the PL peak originate from small size crystalline GaN in the almost amorphous film.3.The bandgap energy of InN depends on sputtering conditions. The optical properties near the bandgap energy of sputter deposited InN films should be still further studying.4.The crystalline, electric and optical properties of InN : Si films deposited by reactive sputtering from In and Si composite targets vary largely with dependence on Si contents.