This paper describes a novel finite element thermal analysis model for an AlGaInP-LED micro-array device. We also conduct a transient analysis for the internal temperature field distribution of a 5×5 array device when a 3×3 unit is driven by pulse current. In addition, for broader applications, a simplified thermal analysis model is introduced and its accuracy is verified. The internal temperature field distribution of 100×100 units is calculated using the simplified model. The temperature at the device center reaches 360.6 °C after 1.5 s. In order to solve the heat dissipation problem of the device, an optimized heat dissipation structure is designed, and the effects of the number and size of the heat dissipation fins on the thermal characteristics of the device are analyzed.
A 300 μm×300 μm light emitting diode(LED) chip is divided into nine 80 μm×80 μm units with 30 μm spacing between adjacent ones. After arraying, the total saturation light output power and the maximum injection current are enhanced by 5.19 times and nearly 7 times, respectively. In addition, the test results demonstrate that the illuminance uniformity on the receiving surface reaches the optimum when the spacing between the arrays is equal to the maximum flat condition. The larger the number of arrays, the greater the area with uniform illuminance on the receiving surface.
1/f低频电噪声是评估半导体器件质量和寿命的一个重要因素。由于1/f低频电噪声极其微弱,为了检测它,同时最大程度降低放大器的本底噪声,低噪声放大器的设计和实现是至关重要的一个环节。针对1/f低频电噪声信号的特性,在现有低噪声放大器基础上进行优化改进,设计出一款频率极低的低噪声放大器,在0.1 Hz^100 kHz频率下具有高增益和低噪声特性。仿真结果表明,在10Hz处噪声系数达到1.80 d B。
