Abstract: A group III nitride semiconductor light emitting diode is revealed. A layered structure composed of group III nitrides is formed on the substrate through epitaxy growth of a hexagonal wurtzite crystal structure. The layered structure includes a n-type semiconductor layer, a light emitting layer on the n-type semiconductor layer, and a p-type semiconductor layer on the light emitting layer. A first electrode metal pad is formed on the p-type semiconductor layer and a second electrode metal pad on the n-type semiconductor layer. A direction from the first electrode metal pad to the second electrode metal pad is the same with that of C-axis [0001] of the hexagonal wurtzite crystal structure so as to speed up the movement of electron-hole and improve the combination efficiency of electron-hole by the electric field along the direction of C-axis [0001] in the hexagonal wurtzite crystal structure.

Abstract: A method for analyzing the reliability of optoelectronic elements rapidly is described. A plurality of optoelectronic elements are tested and measured by a spectrum analyzer to obtain noise equivalent power (NEP) and peak of noise power spectrum of each optoelectronic element at a frequency. An electrical cycle test is performed by alternately imposing forward bias and reverse bias on the optoelectronic elements with cycles. Then, the spectrum analyzer tests and measures the optoelectronic elements with the electrical cycle test at the frequency to determine whether the NEP and peak of noise power spectrum of the optoelectronic elements with the electrical cycle test are higher than those of optoelectronic elements without the electrical cycle test. Furthermore, the NEP and peak of noise power spectrum of the optoelectronic elements with the electrical cycle test are compared with the statistic standard deviation to obtain the optoelectronic elements having reliability problems.

Abstract: A method for analyzing the reliability of optoelectronic elements rapidly is described, which has a spectrum analyzer to test and measure NEP and peak of noise power spectrum of the optoelectronic elements at the low frequency. The optoelectronic elements are imposed with the appropriate forward bias and reverse bias to generate alternate variable cycles of positive and negative currents. After appropriate iteration cycles, cycle time and duty cycles, the spectrum analyzer tests and measures the optoelectronic elements after the electrical cycle test to determine whether the NEP and peak of noise power spectrum of the optoelectronic elements at the low frequency are higher than those of optoelectronic elements without the electrical cycle test. The NEP and peak of noise power spectrum of the optoelectronic elements are then compared with the statistic standard deviation to find out the optoelectronic elements having some problems of the reliability.

Abstract: A photodetector is disclosed, comprising: a substrate; a GaN-related material layer of a first conductivity type located on the substrate; an intrinsic layer located on a portion of the GaN-related material layer of the first conductivity type; a first GaN-related material layer of a second conductivity type located on the intrinsic layer; a second GaN-related material layer of the second conductivity type located on the first GaN-related material layer of the second conductivity type; an electrode of the second conductivity type located on a portion of the second GaN-related material layer of the second conductivity type; and an electrode of the first conductivity type located on another portion of the GaN-related material layer of the first conductivity type.

Abstract: A novel structure for a photodiode is disclosed. It is comprised of a p-type region, which can be a p-substrate or p-well, extending to the surface of a semiconductor substrate. A multiplicity of parallel finger-like n-wells is formed in the p-type region. The fingers are connected to a conductive region at one end.