| 摘要 |
PURPOSE:To obtain a highly integrated simiconductor image pickup element by disposing an overflow drain under an overflow control gate and reducing an area occupying the blooming preventing structure. CONSTITUTION:Boron is injected as a guard ring 202 to a P type substrate 201, and a field oxidized film 210 is formed using a selective oxidation. Then, to take a direct contact, a hole is opened, a multilayer crystalline silicon layer is formed, phosphorus is diffused, and an overflow drain 203 is formed. Thereafter, a polycrystalline layer is patterned by a photoresist pattern and a plasma etching method to form an overflow control gate 208 and a transfer gate 207. Subsequently, a BDC transfer clock gate 206, a photodiode diffused layer 204 and a light shielding aluminum 209 are formed as a semiconductor image pickup element. |
