The invention discloses a
capacitor structure which comprises an N-type
potential well capacitor and a P-type
potential well capacitor which are connected in parallel. The N-type
potential well capacitor comprises an N-type potential well, an N-type gate structure, an N-type source drain region and an N-type potential well leading-out region. The P-type potential well capacitor comprises a P-type potential well, a P-type gate structure, a P-type source drain region and a P-type potential well leading-out region. The N-type and P-type gate structures are both connected to the first capacitive
electrode. And the N-type and P-type source and drain regions and the N-type and P-type potential well lead-out regions are connected to a second capacitor
electrode. The total
capacitance value between the first capacitor
electrode and the second capacitor electrode is formed by superposing the first
capacitance value of the N-type potential well capacitor and the second
capacitance value of the P-type potential well capacitor. And the first and second
capacitance voltage change curves of the N-type and P-type potential well capacitors are complementary in size, so that the total capacitance value stably changes along with the
voltage. According to the invention, the capacitance value which stably changes along with the
voltage can be provided,
process integration is facilitated, and additional
mask plates and
ion implantation processes are not needed.