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A new approach to fabricating high-quality AlInGaN film as a lattice-matched barrier layer in multiple quantum wells(MQWs) is presented. The high-quality AlInGaN film is realized by growing the AlGaN/InGaN short period superlattices through metalorganic chemical vapor deposition, and then being used as a barrier in the MQWs. The crystalline quality of the MQWs with the lattice-matched AlInGaN barrier and that of the conventional InGaN/GaN MQWs are characterized by x-ray diffraction and scanning electron microscopy. The photoluminescence(PL) properties of the InGaN/AlInGa N MQWs are investigated by varying the excitation power density and temperature through comparing with those of the InGaN/GaN MQWs. The integral PL intensity of InGaN/AlInGaN MQWs is over 3 times higher than that of InGaN/GaN MQWs at room temperature under the highest excitation power. Temperature-dependent PL further demonstrates that the internal quantum efficiency of InGaN/AlInGaN MQWs(76.1%) is much higher than that of InGaN/GaN MQWs(21%).The improved luminescence performance of InGaN/AlInGaN MQWs can be attributed to the distinct reduction of the barrier-well lattice mismatch and the strain-induced non-radiative recombination centers.
A new approach to fabricating high-quality AlInGaN film as a lattice-matched barrier layer in multiple quantum wells (MQWs) is presented. The high-quality AlInGaN film is realized by growing the AlGaN / InGaN short period superlattices through metalorganic chemical vapor deposition, and then being used as a barrier in the MQWs. The crystalline quality of the MQWs with the lattice-matched AlInGaN barrier and that of the conventional InGaN / GaN MQWs are characterized by x-ray diffraction and scanning electron microscopy. The photoluminescence (PL) properties of the InGaN / AlInGaN MQWs are investigated by varying the excitation power density and temperature through comparing with those of the InGaN / GaN MQWs. The integral PL intensity of InGaN / AlInGaN MQWs is over 3 times higher than that of InGaN / GaN MQWs at room temperature under the highest excitation power. Temperature-dependent PL further demonstrates that the internal quantum efficiency of InGaN / AlInGaN MQWs (76.1%) is much higher than tha t of InGaN / GaN MQWs (21%). The improved luminescence performance of InGaN / AlInGaN MQWs can be attributed to the distinct reduction of the barrier-well lattice mismatch and the strain-induced non-radiative recombination centers.