AVS 58th Annual International Symposium and Exhibition
    Electronic Materials and Processing Division Thursday Sessions
       Session EM-ThP

Paper EM-ThP12
Effect of Buffer Layers on Structural and Optical Properties of InN Films by RF-MOMBE

Thursday, November 3, 2011, 6:00 pm, Room East Exhibit Hall

Session: Electronic Materials and Processing Poster Session
Presenter: Wei-Chun Chen, National Applied Research Laboratories, Taiwan, Republic of China
Authors: W.C. Chen, National Applied Research Laboratories, Taiwan, Republic of China
S.Y. Kuo, Chang Gung University, Taiwan, Republic of China
F.-I. Lai, Yuan-Ze University, Taiwan, Republic of China
C.-T. Lee, National Applied Research Laboratories, Taiwan, Republic of China
C.N. Hsiao, National Applied Research Laboratories, Taiwan, Republic of China
D.P. Tsai, National Applied Research Laboratories, Taiwan, Republic of China
Correspondent: Click to Email
Hexagonal InN films were prepared on sapphire by RF-MOMBE using AlN, GaN and ZnO buffer layers. Also, we have investigated the effect of buffer layers on optical, structural and electrical properties of InN films. The crystalline quality of the InN film is sensitive to the underlying buffer layer when the film is grown under the high effect V/III ratio condition. The structural, optical and electrical properties of InN films were investigated by X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), UV/VIS/IR spectrum measurements, and Hall effect, respectively. The XRD pattern indicated all InN films along c-axis growth. Optical absorption edge by spectrophotometer confirms that the band gap of wurtzite InN films were 1 to 1.2 eV. A Hall mobility of more than 170 cm2/V-s with a carrier concentration of 9.2 × 1019 cm-3 at room temperature can be routinely obtained on InN/GaN film. Also, the average later thicknesses range measured about 800 to 1000 nm, and high growth rate about 1.6 mm/hr at InN/GaN, 2 mm/hr at InN/ZnO and 1 mm/hr at InN/AlN, respectively. We suggest that the reduced lattice mismatch between the InN epilayer and top buffer layer is responsible for improvement of sample quality using the buffer-layer technique.