摘要
利用同步辐射光电子能谱技术研究了低Sr组分时Pb_(1-x)Sr_xTe薄膜能带的移动规律,并计算了Pb_(1-x)Sr_xTe/Pb Te异质结中导带帯阶所占比率.当不考虑应力时,该异质结界面导带带阶比率Qc=ΔEC/ΔEg=0.71.当考虑应力时,PbTe能带发生L能谷与O能谷的劈裂,其导带带阶比率分别为QLC=0.47和QOC=0.72.Pb_(1-x)Sr_xTe/Pb Te异质结界面具有类型Ⅰ的能带排列结构,这说明Pb_(1-x)Sr_xTe/PbTe型量子阱或量子点对电子与空穴都有较强的限制能力.该异质结能带帯阶的精确测量有利于该类三元系半导体异质结在中红外光电器件的研发和应用中发挥重要作用.
The valence band shift in Pb_（1-x）Sr_xTe thin films with different Sr compositions was studied.The ratio of conduction band offset and valence band offset in this heterostructure has been determined.Without considering the strain effect,the conduction band offset ratio is Qc= ΔEc/ ΔEg= 0. 71,and with considering the strain effect,the energy band of Pb Te is degenerated into longitudinal and oblique valleys. The conduction band offset ratio for longitudinal valley is QLC= 0. 47 and for oblique valley is QOC= 0. 72,respectively. Pb_（1-x）Sr_xTe / Pb Te heterostructure has a type Ⅰ alignment at the interface,which implies the confinement of both electrons and holes. The accurate determination of band alignment of Pb_（1-x）Sr_xTe / Pb Te heterostructure has great benefits in the research and development of mid-infrared opto-electronic devices.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
2016年第2期214-218,226,共6页
Journal of Infrared and Millimeter Waves
基金
国家自然科学基金(61275108
11374259)
浙江省自然科学基金(Z1110057
LY15F050009)
浙江省教育厅科研项目(Y201430784)
浙江大学城市学院教师科研基金(J-15011)~~
