| 摘要 |
PURPOSE:To reduce greatly pickup noise of a detection electrode by reducing the detection electrode in area by arranging a bias electrode, island electrode, and detection electrode and transfer electrode in three-layer structure. CONSTITUTION:Bias electrodes 70-72 made of metal are arranged in parallel to main channel 33 or correction channel 37 and extending to both sides of a channel stop and applied with direct-current potential VSE. Further, metal island-shape electrode 73 is arranged inside of channel 33. Those electrodes 70-73 form a 1st layer. Detection electrodes 74 and 75, providing non-destructive detection of signal charge, are partitioned into two parts on electrode 73 and formed of a 2nd-layer metal electrode together with transfer electrodes 22, 29 and 30. Other transfer electrodes 21, 23 and 28 form a 3rd-layer transfer electrode. The weight coefficiency of a tap of this filter is in proportion to a difference between the channel width of electrode 74 and that of electrode 75 and it is determined by single alignment, so that an alignment shift will never occur. The above-mentioned layer-electrode structure is employed in this way to make it possible to reduce the area of the detection electrode. |
