【摘 要】
：
Ga(In, Al)N alloys are used as an active layer or cladding layer in light emitting diodes and laser diodes. x-raydiffraction is extensively used to evaluate the
【机 构】
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School of Physics, Peking University, Beijing 100871
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Ga(In, Al)N alloys are used as an active layer or cladding layer in light emitting diodes and laser diodes. x-raydiffraction is extensively used to evaluate the crystalline quality, the chemical composition and the residual strain in Ga(Al,In)N thin films, which directly determine the emission wavelength and the device performance. Due to the minor mismatch in lattice parameters between Ga(Al, In)N alloy and a GaN virtual substrate, x-ray diffraction comes to a problem to separate the signal from Ga(Al,In)N alloy and GaN. We give a detailed comparison on different diffraction planes. In order to balance the intensity and peak separation between Ga(Al, In)N alloy and GaN, (0004) and (10-15) planes make the best choice for symmetric scan and asymmetric scan, respectively.
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