n-type GaN layers were grown at 950 degrees C by metallorganic vapor-phase epitaxy using a pulse injection (PI) method. Carrier densities of 1.6 x 10(19) cm(-3) and atomically flat surfaces were realized at 950 degrees C by decreasing the partial pressure of trimethylgallium (TMGa) to enhance the surface migration of Ga-species and reduce carbon incorporation. The intersubband transition (ISBT) in AlN/GaN multiquantum wells was first appeared using the PI method, and the ISBT properties were much improved compared to those of MQWs grown by the conventional method. This improvement was due to the improved interface abruptness and layer uniformity. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3533660] All rights reserved.