本文研究了低温GaN(LT-GaN)缓冲层表面形貌,其随厚度的变化规律及对随后生长GaN外延膜各项性能的影响.用场发射扫描电镜(SEM)和原子力显微镜(AFM)研究LT-GaN缓冲层表面形貌,发现随着厚度的增加,其表面由疏松、粗糙变得致密、平整,六角GaN小晶粒的数量减少,且取向较为一致.用X光双晶衍射(XRD)、AFM和Hall测量研究1μm厚本征GaN外延薄膜的结晶质量、表面粗糙度、背底载流子浓度和迁移率等性能,发现随着LT-GaN缓冲层厚度的增加:XRD的半高宽FWHMs增大,表面粗糙度先减小后又略有增大,背底载流子浓度则随之减少,而迁移率的变化则不明显.通过分析进一步确认LT-GaN缓冲层的最优生长时间.
参考文献
[1] | Akasaki I. .Nitride semiconductors - impact on the future world[J].Journal of Crystal Growth,2002(Pt.2):905-911. |
[2] | Gil B.Group Ⅲ Nitride Semiconductor and Compounds: Physics and Application[M].Oxford:Clarendon Press,1998 |
[3] | Nakamura S;Mukai T;Senoh M .Candela-class High-brightness InGaN/AIGaN Double-heterostructure Blue-light-emitting Diodes[J].Applied Physics Letters,1994,64:1687. |
[4] | RAMAIAH K S;Su Y K;Chang S J;Kerr B .Characterization of InGaN/GaN Multi-quantum-well Blue-light-emitting Diodes Grown by Metal Organic cChemical Vapor Deposition[J].Applied Physics Letters,2004,84:3307. |
[5] | Nakamura S;Senoh M;Nagahama S;Iwasa N, Yamada T, Matsushita T, Sugimoto Y, Kiyoku H .Continuous-wave Operation of InGaN Multiquantum-well-structure Laser Diodes at 233 K[J].Applied Physics Letters,1996,69:3034. |
[6] | Chini A.;Coffie R.;Meneghesso G.;Zanoni E.;Buttari D.;Heikman S. Keller S.;Mishra UK. .2.1 A/mm current density AlGaN/GaN HEMT[J].Electronics Letters,2003(7):625-626. |
[7] | Youn D H;Lee J H;Kumar V;Schwindt R, Chang W J, Hong W J, Jeon C M, Bae S B,Park M R, Lee K S, Lee J L, Lee J H,Adesida I .High Power 0.25 μm Gate GaN HEMTs on Sapphire with Power Density 4.2W/mm at 10 GHz[J].Electronics Letters,2003,39:339. |
[8] | Maruska H P;Tietjen J J .The Preparation and Properties of Vapor-deposited Single-crystal-line GaN[J].Applied Physics Letters,1969,15:327. |
[9] | pankove J I;Chichibu S F .Luminescent Properties of GaN[J].Solid State Communications,1970,8:1051. |
[10] | Amano H;Sawaki N;Akasaki I;Toyoda Y .Metalorganic Vapor Phase Epitaxial Growth of a High Quality GaN Film Using an AlN Buffer Layer[J].Applied Physics Letters,1986,48:353. |
[11] | Nakamura S .GaN Growth Using GaN Buffer Layer[J].Japanese Journal of Applied Physics,1991,30:1705. |
[12] | Mosca M;Reverchon J L;Omne F;Duboz J Y .Effects of the Buffer Layers on the Performance of( Al, Ga) N Ultraviolet Photodetectors[J].Journal of Applied Physics,2004,95:4367. |
[13] | Wang T;Shirahama T;Sun H B;Wang H X, Bai J, Sakai S, Misawa H H .Influence of Buffer Layer and Growth Temperature on the Properties of an Undoped GaN Layer Grown on Sapphire Substrate by Metalorganic Chemical Vapor Deposition[J].Applied Physics Letters,2000,76:2220. |
[14] | Sumiya M;Ogusu N;Yotsuda Y;Itoh M, Fuke S .Systematic Analysis and Control of Low-temperature GaN Buffer Layers on Sapphire Substrates[J].Journal of Applied Physics,2003,93:1311. |
[15] | Kim Y;Subramanya S G;Siegle H;Kruger J, Perlin P, Weber E R .GaN Thin Films by Growth on Ga-rich GaN Buffer Layers[J].Journal of Applied Physics,2000,88:6032. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%