Study on the Fabrication of RPAS Micro-lens Array for CCD Integration

摘要

The micro-lens array for CCD systems can enhance the utilization efficiency of light energy, then improve its detection sensitivity. This paper firstly researches on the principle of micro-lens array for CCD integration, the lens changing refractive index theory and the mechanism of ionic exchange on glass materials. Then, with reasonable design of the mask and optimization the ionic exchange process parameters, the paper finally produces the Rectangular Plane Arched Shape (RPAS) micro-lens array on the plate glasswith the unit feature size being 22μm × 22μm. The results show that the RPAS micro-lens array's fill factors could be achieved 93%, and the spectral sensitivity can be improved by 0.3 times. The mask plays a decisive role in micro-lens which is manufactured by ionic exchanged method. The reasonable selection of the mask parameter can eliminate the void that in the circular aperture planar micro-lens array, and enhance the fill factor; in the ionic exchange process, it is easy to obtain the large refractive index by using the ion-pair that have big differences. The ionic exchanged temperature below the glass softening temperature at about 20℃ is appropriate.