| 摘要 |
PURPOSE:To enable charge transfer at high speed by small power consumption by forming a thin layer having a conduction type reverse to a semiconductor substrate having one conduction type on the upper surface of the substrate and providing a means completely depleting the thin layer and shaping a charge transfer elctrode on an insulating film formed on the thin layer. CONSTITUTION:When voltages are applied in three-phase pulses of phi1=phi3=0 and phi2= positive and there are signal charges under a phi2 electrode, reverse bias voltage 303 is increased sufficiently, and P type semiconductor thin layer 302 is depleted completely. A series capacitance of the capacitance of SiO2 102, the capacitance of the depleted P type thin layer and the capacitance of a depleted N substrate is obtained at that time. Since the capacitance of the depleted N substrate can be designed arbitrarily in a small value when donor concentration is lowered, a capacitance viewed from the electrode can also be reduced arbitrarily. The capacitance of potential in the depth direction under phi1, phi3 electrodes can be minimized arbitrarily when the donor concentration of the N substrate is lowered similarly. Signal charges transfer under the phi3 electrode on the right side of the phi2 electrode when phi1=phi2=0 and phi3 is brought to positive potential, and signal charges transfer under the phi1 electrode on the right side of the phi3 electrode when phi2=phi3=0 and phi1 is brought to positive potential. |
