氧气流量对Mg_x Zn_(1-x)O薄膜择优取向的影响

Influence of Oxygen Flow on the Preferred Orientation of Mg_xZn_(1-x)O Film

利用脉冲激光沉积技术,选用靶材为Mg0.5Zn0.5O陶瓷靶材,在非晶石英衬底上研究氧气流量对MgxZn1-xO合金薄膜生长取向的影响。结果表明:在低压、低氧气流量条件下薄膜的成核生长主要受控于晶面的表面能,薄膜为(200)晶向;在沉积压强8.0 Pa时,随着氧气流量的增加,反应粒子的能量降低,不同取向晶粒的生长速率发生变化,导致MgZnO薄膜的生长取向由(200)择优取向转变为(111)择优取向。当氧气流量过大(70 sccm)时,由于氧气分子迁移能的提高,MgZnO薄膜呈现多个不同生长取向。

MgxZn1-x O films were deposited on amorphous SiO2 substrates by pulsed laser deposition method. The effects of oxygen flow on the growth orientation of MgxZn1-xO films were studied. The results indicates that at low air pressure and low flux of oxygen the nucleation and growth of MgZnO films is controlled by surface energy, MgZnO thin films is （200） oriented. But at 8 Pa air pressure condition, as the oxygen flow rate increasing, the growth velocity of different orientation grain changed, it leads to the preferred orientation of MgZnO film changed from （200） to （ 111 ）, finally, orientation of （200） and （ 111 ） exist together at 70 sccm oxygen flow.