Solid-state imaging device and method for controlling same

A method for controlling a solid-state imaging device comprising:

• a semiconductor substrate;
• a nonvolatile memory transistor which is formed on the semiconductor substrate and which has a charge storage layer and a control gate, a photoelectric converting region being arranged below the charge storage layers and in the semiconductor substrate, the nonvolatile memory transistor being irradiated with light to generate charges in the photoelectric converting region and to inject the charges into the charge storage layer, the charges being stored in the charge storage layer as pixel information;
• and
• at least two selecting gate transistors, each of which is formed on both sides of the nonvolatile memory transistor so as to share a diffusion layer with the nonvolatile memory transistor,
• wherein a plurality of pixel units are arranged on the semiconductor substrate in the form of a matrix so as to extend in row and column directions, each of the pixel units comprising the nonvolatile memory transistor and two the selecting gate transistors arranged on both sides thereof, the method comprising:
• an erase step for electrically emitting charges from the charge storage layer of the nonvolatile memory transistors;
• an image pickup step for turning off the selecting gate transistors and irradiating the nonvolatile memory transistors with light while a writing voltage is applied to the control gate of the nonvolatile memory transistors, to inject charges generated in the photoelectric converting region of a corresponding one of the nonvolatile memory transistors, into the charge storage layer of the corresponding one of the nonvolatile memory transistors;
• and
• a reading step for reading the pixel information by applying a reading voltage to the control gate of a corresponding one of the nonvolatile memory transistors while the selecting gate transistors are turned on.

A method for controlling a solid-state imaging device comprising:

• a semiconductor substrate;
• a nonvolatile memory transistor which is formed on the semiconductor substrate and which has a charge storage layer and a control gate, a photoelectric converting region being arranged below the charge storage layers and in the semiconductor substrate, the nonvolatile memory transistor being irradiated with light to generate charges in the photoelectric converting region and to inject the charges into the charge storage layer, the charges being stored in the charge storage layer as pixel information;
• and
• at least two selecting gate transistors, each of which is formed on both sides of the nonvolatile memory transistor so as to share a diffusion layer with the nonvolatile memory transistor,
• wherein a plurality of pixel units are arranged on the semiconductor substrate in the form of a matrix so as to extend in row and column directions, each of the pixel units comprising the nonvolatile memory transistor and two the selecting gate transistors arranged on both sides thereof, the method comprising:
• an erase step for electrically emitting charges from the charge storage layer of the nonvolatile memory transistors;
• a pre-writing step for turning off the selecting gate transistors and applying a first writing voltage to the control gates of the nonvolatile memory transistors, to inject charges, which exist in an inversion layer formed in a channel region of a corresponding one of the nonvolatile memory transistors, into the charge storage layer of the corresponding one of the nonvolatile memory transistors, the charges being stored in each of the charge storage layers as dummy pixel information;
• and
• a pre-reading step for reading and storing the dummy pixel information by applying a reading voltage to the control gate of each of the nonvolatile memory transistors while each of the selecting gate transistors are turned on;
• a pre-charging step for pre-charging a channel region of each of the nonvolatile memory transistors on the basis of the dummy pixel information;
• an image pickup step for turning off the selecting gate transistors and irradiating the nonvolatile memory transistors with light while a second writing voltage is applied to the control gate of the nonvolatile memory transistors, to inject charges generated in the photoelectric converting region of a corresponding one of the nonvolatile memory transistors, into the charge storage layer of the corresponding one of the nonvolatile memory transistors, the charges being stored in the charge storage layer as the pixel information;
• and
• a reading step for reading the pixel information by applying a reading voltage to the control gate of a corresponding one of the nonvolatile memory transistors while each of the selecting gate transistors are turned on.