Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Chinese Journal of Luminescence》 2001-03
Add to Favorite Get Latest Update

Influence of Carrier Gas in Metalorganic Precursors on the MOCVD Growth of InGaN Films

WANG Li, LI Shu ti, PENG Xue xin, XIONG Chuan bing, JANG Feng yi (Institute of Materials Science, Nanchang University, Nanchang 330047, China)  
The InGaN/GaN films were grown by metalorganic chemical vapor deposition (MOCVD) at atmospheric pressure. Properties of these films, such as their chemical component, thickness, the crystalline quality, and optical properties, were investigated by Rutherford backscattering / channeling measurement and photoluminescence measurement. The growth was carried on (0001) oriented sapphire substrates. TEGa, TMGa, TMIn, and blue ammonia (NH 3) were used as Ga, In, N precursors, respectively . Before the growth, a thin buffer layer with thickness of about 15nm was deposited at 520℃ and crystallized at 1 060℃ for 6 minutes. In the growth of this layer, the / ratio in gas phase was adjusted to achieve good quality of GaN films and prevent the cracks usually occurred. GaN films were grown at 1 060℃ . After growth, the temperature was decreased to 650~800℃ to grow In x Ga 1-x N layers . Two In x Ga 1-x N samples were discussed in this paper. During the growth, the flow rates of NH 3, TMIn, and TEGa were 1 l/min , 2 8μmol/min and 1 6μmol/min, respectively. The growth temperature was 760℃ and N 2 was used as main carrier gas. Sample A used 70ml/min H 2 as the carrier gas of metalorganic precursors, but sample B used 70ml/min N 2. The In mole fraction and growth rate of In x Ga 1-x N films were largely influenced by the carrier gas in metalorganic precursors when the main carrier gas was N 2. The In mole fraction in In x Ga 1-x N alloys was 0 10 in sample B. However, the x value was 0 06 in sample A. It means that H 2 can largely influence the In mole fraction in In x Ga 1-x N films, even the flow rate of H 2 was very small. This result is in agreement with other reports. The value of the growth rate was 10 6nm/min for sample A, and that was 6 0nm/min for sample B. This phenomena, the dependence of the InGaN growth rate on little precursors carrier gas H 2 have never been reported to our knowledge. We considered that H 2 can reduce the lifetime of the reactive In atoms at the film surface during growth, which lead to the increasing of Ga atoms in the film surface. So, the growth rate of alloys increased.
【Fund】: 国家“8 6 3”新材料领域 ( 715 -0 0 1-0 0 12 ) ;; 国家自然科学基金 ( 6 96 76 0 19);; 江西省跨世纪人才
【CateGory Index】: TN304055
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved