01 May 2009 In back-thinned CCDs the silicon substrate is thinned to only a few tens of microns thick. This means that infrared light is more likely to pass through the substrate thus resulting in a loss of quantum efficiency (QE).
Thickening the silicon substrate increases the QE in the near-IR region but also reduces the resolution unless a bias voltage is applied. Hamamatsu Photonics have introduced fully depleted CCDs using a unique thick silicon substrate that has no neutral region when a bias voltage is applied, and therefore deliver higher QE in the near-IR region, whilst maintaining a high resolution. This improved near-IR sensitivity makes fully depleted back-thinned CCDs well suited for astronomy applications. | 
