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对使用 MOCVD方法在蓝宝石衬底上生长的典型 In Ga N样品进行了光致发光 (PL)、霍耳 (Hall)及扫描电镜 (SEM)测量 .结果表明 :适当的生长温度 (75 0℃ )提高了样品中 In的含量和 PL 强度。当 / 族比率大约 5 0 0 0时 ,75 0℃生长的样品背景载流子浓度约为 2 .2 1× 10 1 8cm- 3,In含量约为 11.5 4% .其室温 394nm的带边峰 ,半高宽约为 116 me V,束缚能约为 32 .4m e V,可能与束缚激子发光相关 .该样品禁带宽度随温度变化的温度系数 α (d E/ d T)约为 0 .5 6× 10 - 3e V/ K.较高温度 (80 0℃和 90 0℃ )生长的样品 In含量较低 ,PL 强度较弱 ,且在样品表面析出了金属 In滴
Photoluminescence (PL), Hall and scanning electron microscopy (SEM) measurements of a typical In Ga N sample grown on a sapphire substrate using the MOCVD method were performed. The results show that the proper growth temperature (75 0 ℃) Increase the In content and PL intensity in the sample. The carrier concentration at 75 0 ℃ is about 2.2 × 10 18 cm -3 and the In content is about 11.5 4% when the ratio is about 500. The peak at 394 nm , The FWHM is about 116 meV, and the binding energy is about 32. 4m eV, which may be related to the emission of bound excitons. The temperature coefficient α (d E / d T) of the bandgap with temperature is about 0 .5 6 × 10 - 3e V / K. In samples grown at higher temperature (80 ℃ and 90 ℃), In content was lower, PL intensity was weaker, and metal In droplets were precipitated on the sample surface