A high sensitivity, 1/2 inch Inter-Line-CCD imager with new photodiode structure consist of a Lateral Overflow Gate and a photodiode was proposed. Especially, We developed a low noise photodiode structure in order to reduce noises on the micro-fluctuation of dark current, that mainly limiled the sensitivity of a CCD imager at high temperature device operation (60℃). These noises were reduced to 0.02nA peak-peak at 60℃ by the new Burried Barrier Structure, which were acceptable for a CCD imager compared with the random noise.
A 1-inch optical format frame interline transfer CCD image sensor with 1920(H) × 1036(V) pixels has been developed for an HDTV camera. This device has the Al wiring in the image area reducing the voltage drop of drive pulse for V-CCD and has the spreading shape transfer gate in H-CCD improving the transfer efficiency in dual channel H-CCD. It achieves a horizontal resolution of 1000 TV lines, a sensitivity of 70 nA/lx, a dynamic range of 72dB and a smear reduction of -100dB.
A 648x487 pixel PtSi Schottky-barrier infrared CCD image sensor was developed. Due to developing the Modified Inverted-LOCOS Process which can minimize dead region in pixel, and Two Dopant Concentration Structure which achieves both large charge handling capability and high transfer efficiency, a 40% fill factor of 21x21 μm size pixel and 12MHz CCD driving were obtained. Noise equivalent temperature difference (N.E.T.D.) was 0.1 Kelvin.
This paper describes a new color linear CCD image sensor designed for the digital color copy machine. To accomplish 6-line-space configuration, which is one half compared to the conventional one, the device adopts the transfer gate less (TGL) structure and 3-level clock operation. Unlike the conventional TGL area image sensors, however, the device can operate with 2-level external clocks. This is achieved by an on-chip 3-level creation circuit which is mad by CMOS-CCD process. The reduction of transfer gate capacitance and its clock swing voltage enable the device to operate at up to 20 MHz with a commercially available CMOS driver, such as 74ACO4. Pigment type color filters, not common for the usual color sensor, was used to withstand 10 ^7 lux-hour exposure.
The random noise of a 250k-pixel static induction transistor (SIT) image sensor is evaluated. The random noise is dependent on the bias voltage conditions. Under bias conditions which produce a large image lag, the random noise generated at the pixel is larger than the expected dark current shot noise. The phenomena are caused by the incomplete reset operation of the SIT gate.
A 1/3-inch format 360k pixel interline transfer CCD image sensor has been developed, which is suitable for high resolution and compact size video cameras. To realize wide apertures of the sensor, we introduced new channel-stop diffusion free vertical-CCDs. Moreover, low noise photodiodes and a high sensitive charge detector have been adopted. As a result, the sensor has 1.4 times the photo sensitivity of a conventional 1/2-inch format sensor, having the same pixel number, and has dynamic range of 70dB.