摘要
Ga_(1-x)In_xAs(x>0.53)材料是未来长距离低损耗光纤通信的理想光源材料和探测器材料之一.我们采用水平常压MOCVD系统,在InP衬底上成功地生长了Ga_(1-x)In_xAs(x>0.53)/InAs_yP_(1-y)/Inp异质结材料.其中InAs_(1-y)P_y为组份阶梯变化的多层结构.由样品的(400)面X光衍射结果测定了各层组份.由二次离子质谱(SIMS)得到了样品剖面组份变化结果,证明InAs_(1-y)P_y层组份为阶梯状变化的.通过对光致发光结果和X光衍射结果比较,可以看到,InAs_yP_(1-y)层通过位错和弹性畸变二种方式来释放或积累Ga_(1-x)InxAs与InP间的失配应力,从而减少了Ga_1-xIn_xAs中的失配位错.有效地改善了Ga_(1-x)In_xAs的质量.已获得了x高达0.94表面光亮的Ga_(1-x)In_xAs/InAs_(1-y)P_y/InP异质结材料.
Ga1-xInxAs (x>0.53) may provide the basic of the device (emitter and detector) for the ultralow loss optical fiber communication system. But the Ga1-xInxAs (x>0.53) is lattice-mismatched with InP substrate. And a large number of misfit dislocations will be introduced in epi-layer. So it is difficult to grow high qulity Ga1-xInxAs (x>0.53) on InP substrate.To reduce misfit dislocations, it would be very effective to insert a step-graded composition layer of InAs1-vPr between Ga1-xInxAs and InP.Ga1-xInxAs x>0.53)/InAs1-yPv,/InP heterojunctions were grown by MOCVD in a horizontal, atmospheric pressure reactor. The reactants included trimethylindium (TMIn), trimethylgallium (TMGA), arsine (AsH3) and phosphine (PH3). The substrate was semi-insulating InP (Fe-doped) oriented 2???????/ off (100) towards <110>.The alloys were characterized with measurments of X-ray diffraction, electron microprobe, secondary ion mass spectrmetry (SIMS) and photo-luminescence (PL).The results of SIMS and X-ray diffraction indicated that the composition of InAs1-yPy varied step by step with depth. The layers of step-graded InAs1-yPy were revealed one by one with chemical etching. And the each layer was characterized with X-ray diffraction and PL. It indicated that the misfit stress was accomodated by misfit dislocation or elastic strain in the InAs1-yPy layer, and so the quality of Ca1-xInxAs layer (x>0.53) was improved. The Gao0.06In0.94As/InAs1-yPy/InP with smooth surface has also been obtained.
出处
《发光学报》
EI
CAS
CSCD
北大核心
1992年第1期57-63,共7页
Chinese Journal of Luminescence
基金
国家高技术新材料委员会
