MBE和MOCVD生长的AlGaAs/GaAs GRIN-SCH SQW激光器深中心的比较

应用深能级瞬态谱(DLTS)技术详细研究分子束外延(MBE)和金属有机物化学汽相淀积(MOCVD)生长的AlGaAs/GaAs激光器的深中心。结果表明,在激光器的n-AlGaAs层里除众所周知的DX中心外,还存在着较大浓度和俘获截面的深(电子或空穴)陷阱,它们直接影响着激光器的性能。

GaN的MOCVD生长

GaN是重要的蓝光半导体材料。以TMGa和BH_3为源在(0112)α-Al_2O_3衬底上成功的用MOCVD方法生长了GaN外延层,研究了GaN的表面形貌与结晶学、电学和光学特性。GaN(2110)面的双晶回摆曲线衍射峰的最小半高宽已达16'。并观测到GaN所发出的紫外可见光波段的阴极荧光。

MOCVD生长的II-VI族化合物固溶体组分的热力学分析.2.Hg（1-x）CdxTe体系

对MOCVD生长Hg_(1-x)Cd_xTe进行了热力学分析.所用的起始原材料为Hg、DM-Cd和R_2Te.计算结果一方面表明CdTe优先并入倾向使得在通常的DAG工艺中x值非常不易控制.另一方表明即使在Hg存在的情况下,也可以沉积几平纯的CdTe,这对实现IMP工艺非常有利,计算结果还表明II/VI比对HgCdTe的组分控制起着关键性的作用.在DAG工艺中,较低的II/VI比可以改善对x值的控制能力,LMP-DAG工艺是降低II/VI比的较好途径.还计算了生长温度和反应室压力对固相组分的影响以及LMP-DAG工艺中生长温度与HgCdTe组分对最低汞分压的影响.

MOCVD的InGaAs/GaAs应变层量子阱的低温光致发光研究

利用MOCVD方法得到了高质量的InGaAs/GaAs应变层量子阱材料,4.3nm量子阱10K PL FWHM仅为3.49meV. 通过对样品荧光谱在变激发强度,变温时的峰位,峰形研究,发现,合金组分起伏散射是样品低温荧光谱展宽的主要原因,因而是MOCVD生长中应该首先解决的问题,实验结果还表明, 在讨论低温PL谱形时,必需考虑光生载流子由随机起伏势中高能位置向低能位置的迁移过程.

用MOCVD在非平面衬底上生长的量子阱、量子线及其光学性质

国家自然科学基金

MOCVD生长的平面型InGaAs/InP PIN光电探测器件

讨论了采了MOCVD技术生长的平面型InGaAs／InP PIN器件的光学特性及制备工艺。通过引入InP窗口层并制备合适的抗反射膜, 提高了器件的量子效率, 达到～90％, 采用平面型结构有可能改善器件的稳定性和可靠性。图3参5

InGaAs/InP体材料和量了阱、超晶格材料的低压MOCVD生长及材料特性的测试分析

于2010-11-23批量导入

低压MOCVD生长的InGaAs/InP量子阱的光致发光谱线线宽及量子尺寸效应的测量分析

于2010-11-23批量导入

MOCVD growth of high quality crack-free GaN on Si(III) substrates

High quality crack free GaN epilayers were grown on Si(111) substrates. Low temperature AlN interlayer grown under low V/III ratio was used to effectively eliminate the formation of micro-cracks. It is found that tensile stress in the GaN epilayer decreases as the N/Al ratio decreases used for AlN interlayer growth. The high optical and structural qualities of the GaN/Si samples were characterized by RBS, PL and XRD measurements. The RT-PL FWHM of the band edge emission is only 39.5meV The XRD FWHM of the GaN/Si sample is 8.2arcmin, which is among the best values ever reported.

MOCVD growth of cubic GaN: Materials and devices

Many impressive progresses have been made recently on the growth of cubic-phase GaN by MBE and MOCVD. In this paper, some of our recent progress will be reviewed, including the growth of high quality cubic InGaN films, InGaN/GaN heterostructure blue and green LEDs. Cubic-phase GaN films were grown on GaAs (100) substrates by MOCVD. Growth conditions were optimized to obtain pure cubic phase GaN films up to a thickness of 4 mum. An anomalous compressive strain was found in the as-grown GaN films in spite of a smaller lattice constant for GaN compared with that of GaAs substrates. The photoluminescence FWHM of high quality InGaN epilayers was less than 100 meV The InGaN/GaN heterostructure blue LED has intense electroluminescence with a FWHM of 20 nm.

Characterization of GaSb substrate wafers for MOCVD III-V antimonides

The qualities of GaSb substrates commonly used for the preparation of III-V antimonide epilayers were studied before and after growing GaInAsSb multi-layers by MOCVD using PL, FTIR and DCXD together with the electrical properties and EPD value. The correlation between the substrate qualities and epilayer properties was briefly discussed. The good property epilayers of GaInAsSb and, then, the high preformance of 2.3 um photodetectors were achieved only using the good quality GaSb wafers as the substrates.