The chemical and electrical properties of InGaN quantum wells grown with interrupts: A comprehensive TEM case study

摘要

Using off-axis electron holography, high resolution electron microscopy (HREM) and energy filtering TEM (EFTEM), we have looked at the structure of InGaN multiple quantum wells (MQWs), grown with varying interrupt times. We have measured the piezoelectric field strength, indium concentration and quantum well width. Our results show that indium deposited without an interrupt creates a quantum well with extensive indium fluctuations which have a very weak overall piezoelectric field strength. However using interrupt times ranging from five to thirty seconds creates a quantum well of uniform In composition and an intense piezoelectric field.