类金刚石薄膜作为HgCdTe红外器件增透膜和钝化膜的研究

DIAMONDLIKE FILM AS AN ANTIREFLECTIVE AND PASSIVATION COATING ON HgCdTe INFRARED DEVICES

采用高频等离子化学气相沉积法（ＲＦＣＶＤ）在ＨｇＣｄＴｅ红外器件上沉积类金刚石薄膜。俄歇电子能谱对ＤＬＣ／ＨｇＣｄＴｅ界面分析结果表明类金刚石薄膜中的碳原子对衬底材料影响较小，７０ｎｍ的类金刚石薄膜能抑制衬底组份的外扩散，而且具有纯度较高的类金刚石薄膜外表面层，是一种理想的钝化膜材料。红外透射光谱测试结果表明类金刚石薄膜在较宽的波长范围内（４１２μｍ）具有明显的增透效应。

α C:H films deposited on HgCdTe substrate material by using radio frequency plasma vapor deposition method have been analyzed by Raman spectroscopy, indicating both diamond like and diamond phases appear in these films. The results of analysing the interface of the DLC/HgCdTe by AES show that the outward diffusion of components of the substrate can be barred completely when the thickness of DLC film is more than 700A. The comparison of infrared transmittance spectrum between the HgCdTe wafer and the DLC/HgCdTe shows that the diamondlike film can improve the transmittance property of HgCdTe photoconductive devices obviously over a wide range of wavelength from 4 to 12μm. The maximum value of antireflectivity can reach 26%.