ELECTRIC CHARGE DIRECTLY INJECTION TYPE INFRARED PRINTED IMAGE SENSOR

摘要

PURPOSE:To make an electric charge directly injection type infrared printed image sensor to have low dark current and low noise generating characteristics, and to enlarge injection efficiency thereof by a method wherein a saw-tooth wave generating circuit is connected to electrodes on the common substrate side of a photo diode array, a substrate on the signal processing part side is connected to the earth, an electric power source is made to have long storage time, and made to have a voltage lower than the winthstand voltage of diodes at the coupling part. CONSTITUTION:Because a photo diode 7 is forwardly biased, and a coupling part diode 6 to be used for temporary storage of electric charge is backwardly biased at the instant when a negative saw-tooth wave pulse is applied to an electric power source 14, the greater part of the applied pulse voltage is applied to the coupling part diode 6, and the diode 7 is made to be in the conducting condition. For example, an In face polished to be finished is used for an infrared photo diode array 51, four phase driving CCDs manufactured on an Si (100) crystal wafer 52 are used as CCDs for signal processing, In bump 61 are formed on Al metal layers 58 on the coupling part diodes 54 of the CCDs interposing Ti layers 59, Cu layers 60 between them, and both are pressure-welded. The commons substrate sides of the InSb diodes 54 are led to the upper part of the CCD substrate according to the In bumps 57, and led to a saw-tooth wave pulse generating circuit formed on the same substrate or formded on a chip.