Analysis of doping concentration and composition in wide bandgap AlGaN:Si by wavelength dispersive x-ray spectroscopy

作者：Kusch Gunnar^*; Mehnke Frank; Enslin Johannes; Edwards Paul R; Wernicke Tim; Kneissl Michael; Martin Robert W

来源：Semiconductor Science and Technology, 2017, 32(3): 035020.

DOI：10.1088/1361-6641/aa58cf

• nitrides
• Si doping
• WDX
• AlGaN
• SEM analysis

Detailed knowledge of the dopant concentration and composition of wide band gap AlxGa1-xN layers is of crucial importance for the fabrication of ultra violet light emitting diodes. This paper demonstrates the capabilities of wavelength dispersive x-ray (WDX) spectroscopy in accurately determining these parameters and compares the results with those from high resolution x-ray diffraction (HR-XRD) and secondary ion mass spectrometry (SIMS). WDX spectroscopy has been carried out on different silicon-doped wide bandgap AlxGa1-xN samples (x between 0.80 and 1). This study found a linear increase in the Si concentration with the SiH4/group-III ratio, measuring Si concentrations between 3 x 10(18) cm(-3) and 2.8 x 10(19) cm(-3), while no direct correlation between the AlN composition and the Si incorporation ratio was found. Comparison between the composition obtained by WDX and by HR-XRD showed very good agreement in the range investigated, while comparison of the donor concentration between WDX and SIMS found only partial agreement, which we attribute to a number of effects.

• 出版日期2017-3