Back illuminated photodiodes

摘要

A highly reflecting back illuminated diode structure allows light that has not been absorbed by a semiconductor absorbing region to be back reflected for at least a second pass into the absorbing region. The diode structure in a preferred embodiment provides a highly reflecting layer of gold to be supported in part by a conducting alloyed electrode ring contact and in part by a passivation layer of SixNy. Conveniently this structure provides a window within the contact which allows light to pass between the absorbing region and the reflecting layer of gold.