Fast pore etching on high resistivity n-type silicon via photoelectrochemistry

In this paper, five factors, namely the HF (hydrofluoric acid) concentration, field strength, illumination intensity as well as the oxidizing-power and conductivity of electrolytes were found to strongly affect the fast pore etching. The oxidizing power of aqueous HF electrolyte of different concentrations was especially measured and analysed. A positive correlation between optimal bias and HF concentration was generally observed and the relationship was semiquantitatively interpreted. Pore density notably increased with enhanced HF-concentration or bias even on patterned substrates where 2D (two-dimensional) nuclei were densely pre-textured. The etch rate can reach 400 μm/h and the aspect ratio of pores can be readily driven up to 250.     

Observation of a diverse deviation from macropore-formation theory in silicon electrochemistry

Via anodizing patterned and unpatterned samples with a high HF concentration （[HF]）, the degree of deviation from pore-formation theory was found to be markedly different. Based on the analysis of scanning electron microscope （SEM） micrographs and current-voltage （I - V） curves, the variation of physical and chemical parameters of patterned and unpatterned substrates was found to be crucial to the understanding of the observations. Our results indicate that the initial surface morphology of samples can have a considerable influence upon pore formation. The electric-field effect as well as current-burst-model was employed to interpret the underlying mechanism.     

光读出热成像焦平面阵列的光学与热学设计

针对提出的一种光读出热成像系统 ,对其焦平面阵列的光学和热学特性进行了详细的分析 ,主要涉及法布里珀罗微腔两个反射面的反射率、可动微镜的温度响应、噪声等效温差以及响应时间四个方面。理论分析表明 :当法布里珀罗微腔两个反射面的反射率为 0 .5时 ,能获得较大的输出反射光强和反衬度 ,并保证了输出反射光强尽可能地随微镜位移在 0～λ/ 4范围内呈线性变化 ;可动微镜的温度响应值可达 2 .0 5× 10 -4,噪声等效温差为19.5mK ,热响应时间为 1.5 4× 10 -3 s。     

基于法布里-珀罗微腔阵列的光读出红外热成像器件设计与制作

提出了一种新颖的基于硅基法布里珀罗微腔阵列的光读出红外热成像器件 ,该器件利用光学读出技术将红外图像直接转化为可见光图像 ,其焦平面阵列 (FPA)是一个基于微机电系统 (MEMS)制作的法布里珀罗微腔阵列。阐明了器件的工作原理 ;完成了可动微镜结构、热机械、可见光读出部分设计。理论分析表明 ,对Al/SiO2 双材料体系而言 ,SiO2 厚度应大于 0 .3μm ,其最佳厚度比为 0 .5 98,相应的最大热 机械灵敏度可达 10 -8m/K。采用体硅微机电系统技术 ,实验制作出了 5 0× 5 0焦平面阵列。