Preparatopm amd EL property of Si nano-particle dispersed oxide filmd by ECR plasma oxidation of siricon carbide

本研究利用电子回旋共振(ECR)等离子体对化学气相沉积(CVD)碳化硅衬底进行氧化处理，成功地制备了硅纳米颗粒分散氧化物薄膜。研究了温度、氧分压和晶面(Si面和C面)对薄膜结构和光致发光特性的影响：(1)在N_2-O_2和Ar-O_2气氛中，C面上的氧化层厚度均大于Si面上的氧化层厚度。Ar-O_2气氛中的氧化物生成是在比N_2-O_2气氛中低的氧分压下进行的。在高氧分压下，C面氧化速度快于Si面氧化速度。(2)在Ar-O_2气氛中，当氧化温度为473-673K，氧分压为2.0×10~(-4)&gt；~4.0×10~(-4)&gt；~4.0×10~(-4)&gt；沉积速度约为100 nm/h，Si纳米粒子的直径约为4~5 nm。在550 nm和630 nm处观察到较强的发光峰。随着氧化层厚度的增加和氧化温度的降低，发光峰的强度增加。(3)采用射频磁控溅射方法，在衬底温度从RT到973K的范围内，用SiO靶沉积了SiO薄膜。在RT-773K温度范围内获得了非晶态SiO薄膜，在RT沉积的薄膜中观察到直径约3-4 nm的纳米硅团簇，并在1173K的Ar气氛中进行热处理。在973K沉积的薄膜中观察到直径约为5 nm的纳米硅团簇。在973K下沉积的薄膜在300 nm处观察到了荧光，而在1173K下热处理的薄膜在400 nm处观察到了荧光。

In this research, it succeeded in the preparation of Si nano-particle dispersed oxide films by oxidation of chemically vapor deposited (CVD) SiC substrates using electron cyclotron resonance (ECR) plasma. The effects of temperature, oxygen partial pressure and crystal surface (i. e. Si face and C face) on film structure, and photo-luminescence (PL) characteristics were investigated.(1)The oxide thickness on the C face was larger than that on the Si face in both N_2-O_2 and Ar-O_2 atmospheres. The oxide formation in Ar-O_2 atmosphere proceeded at lower oxygen partial pressures than that in N_2-O_2 atmosphere. The oxidation rates of C-face were faster those of Si-face at high O_2 partial pressures. It was found the ECR plasma was particularly effective to oxidize SiC at low temperatures rather than thermal oxidation and microwave plasma oxidation.(2)Nano-Si dispersed SiO_2 films were obtained at oxidation temperature of 473-673K, oxygen partial pressure of 2.0×10^<-4>〜4.0×10^<-4> Pa in Ar-O_2 atmospheres. Deposition rate was about 100nm/h. Si nano particles size were about 4-5 nm in diameter. Strong PL peaks were observed at wavelength of 550 nm and 630 nm. The intensity of PL peaks increased with increasing oxide thickness and decreasing oxidation temperature.(3)SiO films were deposited by RF magnetron sputtering using a SiO target at substrate temperatures from RT to 973K. Amorphous SiO films were obtained in a range between RT and 773K, Nano-silicon clusters about 3-4 nm in diameter were observed in the film deposited at RT and heat-treated at 1173K in Ar. Nano-silicon clusters around 5 nm in diameter were observed in the film deposited at 973K. PL was observed at a wavelength of 300nm for the film deposited at 973K, and at 400nm for the film heat-treated at 1173K.