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technologies [2017/10/05 14:20]
mlesser [Backside Etching]
technologies [2018/05/20 17:39] (current)
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 ====Detector Packaging==== ====Detector Packaging====
    
-Packaging of our back illuminated CCDs is accomplished by mounting the thinned CCD with its substrate to a metal package. We have designed each silicon substrate to fit into a particular Kovar or Invar package. Each electrical trace on the substrate leads from an indium bump to a wire bonding pad. Commercial Kovar packages are not flat enough for the large area CCDs require ​in spectrographs and for wide field mosaics. By replacing all these packages with custom Invar carriers, we will routinely achieve flat and stable imaging surfaces as well as provide a much simpler I/O connection in the dewar.+Packaging of our back illuminated CCDs is accomplished by mounting the thinned CCD with its substrate to a metal package. We have designed each silicon substrate to fit into a particular Kovar or Invar package. Each electrical trace on the substrate leads from an indium bump to a wire bonding pad. Commercial Kovar packages are not flat enough for the large area CCDs required ​in spectrographs and for wide field mosaics. By replacing all these packages with custom Invar carriers, we will routinely achieve flat and stable imaging surfaces as well as provide a much simpler I/O connection in the dewar.
    
 Standard thermo compression gold ball bonding is used to wire bond from the pad to an I/O pin. To check the reliability of our wire bonds, we pull test each to the required MIL-STD specification. Standard thermo compression gold ball bonding is used to wire bond from the pad to an I/O pin. To check the reliability of our wire bonds, we pull test each to the required MIL-STD specification.