High-resolution CCD linear image sensors for the advanced visible and near-infrared radiometer (AVNIR)

摘要

Abstract: Two types of high resolution CCD linear image sensors have been developed for AVNIR, which will be carried on the Advanced Earth Observing Satellite (ADEOS) in early 1996. One has 10000 pixels (pixel size: 8 $mu@m $MUL 8 $mu@m) with spacing of 8 $mu@m for the panchromatic band (0.52 - 0.69 $mu@m). The other has 5000 pixels (pixel size: 16 $mu@m $MUL 16 $mu@m) with spacing of 16 $mu@m for the multispectral bands (Mu1: 0.42 - 0.50 $mu@m, Mu2: 0.52 - 0.60 $mu@m, Mu3: 0.61 - 0.69 $mu@m, and Mu4: 0.76 - 0.89 $mu@m). These bands are separated by a dichroic prism in the optical system. Each sensor has a staggered layout of Si p-n-p buried photodiodes, and an overflow drain for an anti- blooming and an electronic shutter operation. The sensor for the multispectral band (MU) has 2 CCDs and the sensor for the panchromatic band (PA) has 4 CCDs to reduce operating frequency. To prevent degradation of modulation transfer function (MTF) for the Mu4 band, which is a near-infrared region, we used a staggered arrangement and p$+$MIN$/ on p$+$PLU$/ epitaxial wafers. MTF in Mu4 band is 0.62 and 0.80 at Nyquist frequency (fn) and $HLF fn, respectively. We have developed novel packaging technologies so as to obtain a focal plane flatness of less than 10 $mu@m peak-to-peak. These technologies include a newly developed SiC-Al$-2$/O$-3$/-SiC package and a method to correct a warp of the chip surface. !4