| 摘要 |
<p>A self aligned, nonoverlapping gate structure for a charge coupled device is fabricated by depositing three sets of interleaved polysilicon gate electrodes (22a). The first set of electrodes (22; poly-Si-1) is applied in a planar form and sized to a width of about one-third the spacing of the electrodes of the first set. The second and third sets of electrodes (32, 42, 43; poly-Si-2 and poly-Si-3) are applied to overlap, in turn, portions (32a, 42a, 43a) of the previously applied electrodes. A thick shield layer of SiO2 (28, 38) is deposited and patterned atop the first and second sets of gate electrodes (22a, 32a). After deposition of the third set of electrodes (42a, 43), the shield layers (28, 38) are removed to provide passageways (52, 54) extending beneath the overlapping portions of the second and third sets of electrodes. Such overlapping portions (32a, 42a, 43a) are then removed by etching through the passageways (52, 54), to produce a nonoverlapping, generally planar gate structure.</p> |
