X-ray Diffraction Measurement of GaInNAs/GaAs Double Quantum Well Structures with Novel Analysis Method for Broadening Factors

Abstract

The structural deterioration of GaInNAs/GaAs double-quantum-well (DQW) samples was analyzed by X-ray diffraction measurement with a novel peak broadening method. We effectively analyzed broadening properties by taking the difference between 004 X-ray satellite profiles measured with two different types of scanning configuration: a conventional configuration without a receiving slit and that with an analyzer crystal placed in front of a receiving detector. We found that the broadening due to structural deterioration can be simply and clearly analyzed by focusing attention on the difference between two types of profile shape, particularly at the valley minimum parts of satellite patterns. It is demonstrated that the difference at the valley minimum parts clearly represents various aspects of the deterioration of DQW structures. Particularly, it is remarkable that not only the degree of deterioration of the DQW structures but also the change in broadening mechanism due to the proceeding deterioration can be effectively analyzed. We propose and formulate a new simple method for analyzing the difference in valley shape by introducing two characteristic indices representing the difference. It is experimentally demonstrated that the new method is effective in both sensitively detecting and characterizing the deterioration of DQW structures by identifying broadening due to tilt distribution or lateral size effects of mosaic structures. From these results, it is concluded that the analysis of the valley minimum parts of profiles is a simple and effective tool for X-ray diffraction measurement.