金刚石薄膜的蓝光发射

THE BLUE PHOTOLUMINESCENCE OF THIN DIAMOND FILMS

利用氮化铝陶瓷作为衬底，在不同甲烷与氢气的配比流量下，利用热丝ＣＶＤ方法制备了一个系列的金刚石薄膜，通过测量样品在４３０ｎｍ处的光致荧光（ＰＬ）谱及其Ｒａｍａｎ光谱，给出金刚石薄膜的结构与生长信息．薄膜ＰＬ强度随甲烷浓度增加到３％时达到最大，继续增加甲烷浓度ＰＬ强度下降．

Using AIN ceramic as substrate, we grow a series of diamond films under different CH 4 to H 2 volume ratio. Comparing their temperature dependent PL from room temperature down to 100K and correlating the PL spectra with their Raman shift, we can get some of the structure and growth information. The intensity of diamond s photoluminescence increases with the ratio of CH 4 to H 2 at first, and reaches its maximum when the CH 4 ratio is 3% . Afert that, PL decrease when the CH 4 growth rate continue to increase. We think the PL intensity might be caused by the recombination of defect states(such as stack fault). When the CH 4 concentration increase, the graphite components also increase, which enhance the possibility of non radiative transition.