GaN薄膜的蓝光和红光发射机理研究

由于生长工艺的不完善，非掺杂GaN薄膜中通常存在未知的杂质和缺陷，产生与这些未知杂质和缺陷能级相关的发光。报道了非掺杂GaN薄膜的692nm红色发光．并研究了非掺杂GaN薄膜的蓝、红色发光的发射机理；利用作者提出的吸收归一化光致发光激发光谱，直接测量出了非掺杂GaN薄膜的蓝、红色发光的初始态能级，确定蓝色发光为施主-价带跃迁复合，而红色发光为施主-受主跃迁复合；给出了黄、蓝、红光的发射模型。所取得的结果对于确定未知杂质和缺陷的种类具有重要的参考价值。

Mechanisms of Blue and Red Luminescence of GaN Film

There are unknown impurities and defects usually in unintentionally undoped GaN film due to imperfect growth procedures so that the luminescence related to the energy levels of the unknown impurities and defects occurs. The red luminescence of undoped GaN film at 692 nm is reported. The emitting mechanisms of blue and red luminescence of undoped GaN film are studied. The energy levels of initial states of blue and red luminescence are measured directly in experiments by using a novel absorption-normalized photoluminescent excitation spectroscopy proposed by the authors. It is determined that the blue luminescence originates from the transition of donor to valence band, and the red luminescence is caused by the recombination of donor to acceptor. A complete luminescent model is built up for the blue, yellow and red luminescence of undoped GaN film. The gotten results have important reference values for determination of types of the unknown impurities and defects.