| 摘要 |
PURPOSE:To lengthen the life time of excess carriers and thus contrive the improvement of sensitivity by a method wherein insulation films are arranged respectively on the both main surfaces of a substrate, and the field plates for controlling carrier distribution are respectively formed on each insulation film. CONSTITUTION:An insulation film 9 equal to the insulation film 6 formed on the surface is adhered on the surface of the substrate 1 constituted of a multi-element semiconductor. Simultaneously, the first field plate 10 and the second field plate 20 are respectively arranged outside the both insulation films 6 and 9. Terminals 11 and 12 are respectively provided on these plates, and then positive voltages V1 and V2 are impressed respectively. For the purpose thereof, and N type cumulative layer Z' shown by oblique lines like the inside of the surface is formed on the surface of the substrate 1. By constituting in this manner, since a hole Q' contributed to the operation of a photo detecting element can be passed through only the bulk part X of the substrate without approaching the both main surfaces front and back of the substrate, the sensitivity of the detecting element can be enhanced. Besides, the generation of noises can be restrained. |
