標題: Optical and structural properties of spontaneously formed long-range compositional modulation in (111)A and (111)B AlGaAs
作者: Chin, A
Lin, BC
Gu, GL
Hsieh, KY
電子工程學系及電子研究所
Department of Electronics Engineering and Institute of Electronics
公開日期: 1-六月-1996
摘要: We have studied the spontaneously formed long-range Al-rich and Ga-rich AlxGa1-xAs/AlyGa1-yAs superlattices in both (111)A and (111)B AlGaAs during epitaxial growth. The spontaneously formed compositional modulation has been investigated by cross-sectional transmission electron microscopy in AlxGa1-xAs (x=0.3-0.4) grown on (111)A and (111)B GaAs substrates at 600-700 degrees C. In contrast, similar superstructures are not observed in layers simultaneously grown on (100) substrates. The observed structural compositional modulation is closely related to the large peak energy redshift and peak intensity enhancement in 15 K photoluminescence (PL) of samples grown on both (111)A and (111)B orientations to those on (100). The respective redshifts of PL peak energy for (111)A and (111)B Al0.27Ga0.73As to that of (100) are 137 and 45 meV, while the PL integrated intensity enhancement to (100) amounts to 200 and 2000 times, respectively. The effect of compositional modulation is reduced with the increasing growth temperatures as shown in the considerably less compositionally modulated (111)A and (111)B Al0.40Ga0.60As grown at 700 degrees C. (C) 1996 American Institute of Physics.
URI: http://hdl.handle.net/11536/1232
ISSN: 0021-8979
期刊: JOURNAL OF APPLIED PHYSICS
Volume: 79
Issue: 11
起始頁: 8669
結束頁: 8674
顯示於類別:期刊論文