[Raman spectra and photoluminescence spectra of InGaN/GaN multiquantum wells annealed].
InGaN/GaN multiquantum well, grown by MOCVD on a sapphire substrate and annealed under the conditions of 700 and 900 degrees C x (20 min)(-1), was studied by means of mirco-Raman spectroscopy and photoluminescence. The Raman peak of E2, A1 showed red shift after multiquantum were wells annealed, and the HWHM of Raman peakdecreased imperceptibly. Moreover,the photoluminescence peak of the sample annealed under the condition of 700 degrees x (20 min)(-1) showed a red shift, then appeared a blue shift under the condition of 900 degrees C x (20 min)(-1). These results clearly showed that the sample annealed induced strain stress relief that could explain Raman peak shift, but the piezoelectric field induced the quantum-confined Stark effect, which can't agree with the photoluminescence experiment. Sample annealed could change the width of quantum well and InGa phase segregated; these factors influencing structure of quantum well could explain the results of photoluminescence spectra.
Lü
Guo-Wei
GW
School of Physics, Peking University, Beijing 100871, China.
Tang
Ying-Jie
YJ
Li
Wei-Hua
WH
Li
Zi-Lan
ZL
Zhang
Guo-Yi
GY
Du
Wei-Min
WM
D005708:Gallium / Q000737:chemistry*; D006358:Hot Temperature; D007204:Indium / Q000737:chemistry*; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods; D055668:Photochemical Processes / Q000528:radiation effects; D013053:Spectrophotometry; D013059:Spectrum Analysis, Raman
D007204:Indium; C473348:gallium nitride; D005708:Gallium; C513701:indium nitride