Method of driving a charge detection circuit

Claim 1

A method of driving a charge detection circuit of a floating diffusion type amplifier including a second conductivity type region contacting a first conductivity type semiconductor body, a voltage barrier gate electrode disposed opposite said body and adjacent said second conductivity type region, a CCD gate electrode disposed opposite said body and adjacent said voltage barrier gate electrode, a MOS transistor for resetting said second conductivity type region and employing said second conductivity type region as a source, and a source follower circuit for receiving the voltage at said second conductivity type region as an input signal, said method comprising: simultaneously producing a potential well in the body opposite the CCD gate electrode by applying a first signal to the CCD gate electrode and a potential barrier in the body opposite the voltage barrier electrode adjacent the potential well; transferring electrical signal charges into the potential well; and sequentially transferring portions of the signal charges from the potential well to the second conductivity type region that exceed the potential barrier by applying a staircase signal including a plurality of discrete step changes in magnitude to the potential barrier electrode.

Claim 2

A method of driving a charge detection circuit of a floating diffusion type amplifier including a second conductivity type region contacting a first conductivity type semiconductor body, a voltage barrier gate electrode disposed opposite said body and adjacent said second conductivity type region, a CCD gate electrode disposed opposite said body and adjacent said voltage barrier gate electrode, a MOS transistor for resetting said second conductivity type region and employing said second conductivity type region as a source, and a source follower circuit for receiving the voltage at said second conductivity type region as an input signal, said method comprising: simultaneously producing a potential well in the body opposite the CCD gate electrode by applying a first signal to the CCD gate electrode and a potential barrier in the body opposite the voltage barrier electrode adjacent the potential well; transferring electrical signal charges into the potential well; and sequentially transferring portions of the signal charges from the potential well to the second conductivity type region that exceed the potential barrier by applying a staircase signal including a plurality of discrete step changes in magnitude to the potential barrier electrode.

Claim 5

A method of driving a charge detection circuit of a floating diffusion type amplifier including a second conductivity type region contacting a first conductivity type semiconductor body, a voltage barrier gate electrode disposed opposite said body and adjacent said second conductivity type region, a CCD gate electrode disposed opposite said body and adjacent said voltage barrier gate electrode, a MOS transistor for resetting said second conductivity type region and employing said second conductivity type region as a source, a source follower circuit for receiving the voltage at said second conductivity type region as an input signal, said method comprising: simultaneously producing a potential well in the body opposite the CCD gate electrode by applying a first signal to the CCD gate electrode and a potential barrier in the body opposite the voltage barrier electrode adjacent the potential well by applying a second signal to the voltage barrier electrode; transferring electrical signal charges into the potential well; transferring the portion of the signal charges from the potential well to the second conductivity type region that exceed the potential barrier as a first output signal; resetting the second conductivity type region by turning on the MOS transistor to extract residual electrical signal charges from the second conductivity type region; and after resetting, removing the voltage barrier opposite the voltage barrier electrode by applying a third signal to the voltage barrier electrode and transferring the remaining electrical signal charges from the potential well to the second conductivity type region as a second output signal.

Claim 6

A method of driving a charge detection circuit of a floating diffusion type amplifier including a second conductivity type region contacting a first conductivity type semiconductor body, a voltage barrier gate electrode disposed opposite said body and adjacent said second conductivity type region, a CCD gate electrode disposed opposite said body and adjacent said voltage barrier gate electrode, a MOS transistor for resetting said second conductivity type region and employing said second conductivity type region as a source, a source follower circuit for receiving the voltage at said second conductivity type region as an input signal, said method comprising: simultaneously producing a potential well in the body opposite the CCD gate electrode by applying a first signal to the CCD gate electrode and a potential barrier in the body opposite the voltage barrier electrode adjacent the potential well by applying a second signal to the voltage barrier electrode; transferring electrical signal charges into the potential well; transferring the portion of the signal charges from the potential well to the second conductivity type region that exceed the potential barrier as a first output signal; resetting the second conductivity type region by turning on the MOS transistor to extract residual electrical signal charges from the second conductivity type region; and after resetting, removing the voltage barrier opposite the voltage barrier electrode by applying a third signal to the voltage barrier electrode and transferring the remaining electrical signal charges from the potential well to the second conductivity type region as a second output signal.