直拉硅单晶中位错的光致发光

Photoluminescence of Dislocations in Czochralski Silicon Induced During Crystal Growth

利用低温光致发光谱研究了直拉硅单晶中位错的光致发光 .实验发现普通直拉硅单晶在晶体生长过程中引入的位错密度高于 10 7cm- 2 时 ,位错的发光光谱出现了典型的位错 D1～ D4发光峰 ;而位错密度较低时 ,光谱中没有出现 D1发光峰 .而对于掺氮直拉硅单晶中的位错 ,其发光光谱在 0 .75～ 0 .85 e V范围内均出现了与低位错密度普通直拉硅单晶相同的较宽的谱峰 .而且当含氮直拉硅单晶中位错密度高于 10 7cm- 2 时 ,在 0 .75～ 0 .85 e V范围内则出现了明显的与原生氧沉淀相关的发光峰 .可以认为硅单晶生长过程中引入的位错的发光特性是与位错生成过程中加速了氧沉淀的生成速度以及氮杂质的存在促进氧沉淀生成相关 .

The optical property of dislocations in Czochralski (CZ) silicon induced during crystal growth is investigated with low temperature photoluminescence.It is foun d that the dislocations in nitrogen-free CZ silicon are present with typical D1 ～D4 bands of dislocation when the dislocation density attained to 107cm - 2.However,when the dislocation density is low,there is a broad band at the ran ge of D1 band.As for the nitrogen-doped CZ silicon,it is found that there is a broad band at the range of 0.75～0.85eV,irrespective of the dislocation density. It is concluded that the optical property of dislocations induced during crystal growth is related to the rate of oxygen clustering accelerated by the movement of dislocations and the present of nitrogen atoms.