| 摘要 |
The charge produced by optical sensors(4)arranged in a matrix on the surface of a semiconductor substrate(6)is transferred by first and second transfer electrodes(12,14)buried under the optical sensors(4).The semiconductor substrate(6)has a multilayer structure of a support substrate(16)of silicon,a buffer layer(18),and a thin−film silicon layer(20)of single crystal silicon.A p−region(26)(overflow area)and an n−type region(28)serving as a transfer channel are provided under the optical sensors(4).The first and second transfer electrodes(12,14)are buried between the n−type region(28)and the buffer layer(18).An insulating layer(30)is interposed between the n−type region(28)and the first and second transfer electrodes(12,14).The sensitivity of the optical sensors(4)can be maintained even if the size of them is reduced to increase the number of pixels because in this constitution,no transfer electrodes are present on the surface and the light−receiving area is increased. |
