Effects of growth pressure on the properties of p-GaN layers

✍ Scribed by Yulun Xian; Shanjin Huang; Zhiyuan zheng; Bingfeng Fan; Zhisheng Wu; Hao Jiang; Gang Wang

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 634 KB
• Volume: 325
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2011.04.030

✦ Synopsis

The influence of growth pressure on the properties of p-GaN grown by metal-organic chemical vapor deposition method was investigated. The p-GaN layers were grown at low temperature under growth pressures ranging from 100 to 400 mbar. We find that higher growth pressure leads to lower Mg incorporation in the p-GaN layer and results in high resistivity of p-GaN grown at 400 mbar. By optimizing the Cp2Mg/TMGa ratio, however, low sheet resistivity can be achieved for p-GaN grown at 100-300 mbar. The p-GaN grown at 300 mbar using optimal Cp2Mg/TMGa ratio of 1.3% shows the highest hole concentration of 5.0 Â 10 17 cm À 3 and the consequent minimum sheet resistivity of 2.6 Â 10 4 O/sq. The superior electrical properties are ascribed to the reduction of compensation effect for the layer grown under the high growth pressure.