Se+注入ZnSe晶体的深能级研究

将Se离子注入到ZnSe晶体中,用深能级瞬态谱仪(DLTS)测量了注Se+前后ZnSe晶体中深能级的变化,发现在ZnSe中经常出现的分别位于导带下0.30eV和0.33eV的两个能级在注Se+和退火后消失。这个结果进一步证实了Beomi等人提出的以上两个能级分别与Se双空位和包含一个Se单空位的复合体有关的论点。同时注Se+后在导带下0.34eV出现一个新的能级,其电子俘获截面明显区别于0.33eV能级。该能级可能与Se填隙原子或占Zn位的反位Se原子有关。

INVESTIGATION OF DEEP LEVEL IN Se+-ION-IMPLANTED ZnSe CRYSTAL

ZnSe has the potential to be used to make blue LED because it has wide band gap, and its strong blue exciton luminescence is observed even at the room temperature1]. The main obstruction in practice is that the p-type ZnSe with low resistivity is difficult to produce due to self-compensation. It seems that the self-compensation effect is related to the native defects originating in nonstoich-iometry during crystal growth1]. The two electron traps which are located at 0.30 and 0.33eV (labeled as A and B thereafter) below conduction band are commonly observed in ZnSe. Some authors suggested that these traps be associated with Se vacancies3,4].