| 摘要 |
PHB. 32,531. A bulk channel imaging charge coupled device for example for converting an infra-red radiation pattern into electrical signals, wherein the layer in which packets of majority charge carriers representative of pattern information are generated and transported to an output comprises, in addition to the background doping concentration substantially determining the layer conductivity, a second impurity concentration provided at least locally and extending over only part of the thickness of the layer and consisting of at least one deep level impurity, said second concentration providing trapping centres for majority charge carriers which can be released by radiation excitation into potential minima occurring in the layer part spaced from the said part containing the second concentration. In one form the semiconductor body is of silicon and the second concentration is provided by an implanted concentration of indium adjacent the layer surface on which the insulated transfer electrodes are present, the device being constructed for imaging an infra-red pattern in the 3 to 5 micron band. In another form the deep level impurity concentration is provided adjacent the major side of the layer remote from the layer surface on which the insulated transfer electrodes are present, the layer at said surface comprising a more highly doped portion and providing for the possibility of a larger charge handling capability than the said one form. |
