A wide-ranging experimental approach reveals a linear relationship between photoluminescence band peak energy and measured indium fraction for In[x]Ga N epilayers with 0 < x < 0.40. We examine the dependence of the emission spectrum on composition using local measurements of the average indium content by Rutherford backscattering spectrometry, energy dispersive X-ray analysis, extended X-ray absorption fine structure and wavelength dispersed electron probe micro-analysis. Corresponding absorption and photoluminescence excitation data reveal the existence of a supplementary linear relationship between the optical bandgap and the indium fraction. Our observations provide definitive and conclusive evidence that the optical properties of InGaN do not conform to current theoretical descriptions of alloy band structure.
|Number of pages||2|
|Journal||Materials Science and Engineering B|
|Publication status||Published - 22 May 2001|
- Bowing parameter
- nitride semiconductors
- pptical properties
- Stokes' shift