Photosensitive composite dielectric gate MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) detector

Abstract

The invention relates to an arrangement method of a photosensitive composite dielectric gate MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) detector. Each unit detector has a structure that N-shaped semiconductor regions are respectively arranged at both upper sides of a P-shaped semiconductor material of a substrate, two insulated dielectric material layers and a control grid electrode are respectively arranged over the substrate, a photoelectron storage layer is arranged between the two insulated dielectric material layers, the second insulated dielectric in contact with the control grid is made of a material preventing charges stored in the photoelectron storage layer from flowing into the grid electrode, a source electrode and a drain electrode are in suspended structures when photoelectrons are collected and stored to the photoelectron storage layer, the first insulated dielectric is a bottom dielectric and adopts silica, SiON or other dielectric materials with high dielectric constants, the second insulated dielectric layer is made from a top dielectric and adopts silica / silicon nitride / silica, silica, alumina or other dielectric materials with high dielectric constants, and the substrate layer or the grid electrode surface is provided with at least one transparent or semi-transparent window for detecting the wavelength of the detector.

Description

1. Technical field [0001] The invention relates to an imaging detection device, especially the structure, working mechanism, setting and operation method of an imaging detection device in the infrared, visible light band to ultraviolet band. 2. Background technology [0002] The currently developed imaging detection devices are mainly CCD and CMOS-APS. The basic working principle of CCD devices is related to the physical mechanism of metal-oxide-silicon (MOS) capacitors. The basic unit of CCD is MOS capacitors, and its working process is mainly signal Charge generation, storage, transfer and detection. CCD is a device that stores and transfers signals in the form of charge packets. Its outstanding feature is that it uses charges as signals, which is different from other devices that use current or voltage as signals. When the CCD is working, the clock pulse voltage is used to generate and control the change of the semiconductor potential well, thereby realizing the storage ...

AI Technical Summary

Problems solved by technology

[0012] CCD CMOS-APS leakage current Very good <1nA / cm2 Bad>50nA / cm2 Duty cycle (Fill Factor) very good ~ 100% Not good <60% Process requirements and very high generally Yield Low yield High yield Compatibility with CMOS process incompatible compatible

[0013] Limitations of CCD and CMOS-APS: CCD and CMOS-APS are imaging elements widely used in today's scientific instruments to household imaging equipment, but the existing two imaging elements have their insurmountable shortcomings

[0014] 1) Imaging speed is difficult to increase: CCD imaging process needs to physically move charges, therefore, its imaging speed is difficult to increase

[0015] 2) Low yield: due to its interconnected MOS capacitor architecture and the need to transfer charges, in the same row of CCD pixels connected in series, any MOS capacitor failure or malfunction will affect the normal transfer of charges in the capacitor, resulting in The pixels after the capacitor in the row of CCD pixels cannot work normally

Therefore, it requires extremely high process control, so the yield is usually low and the production cost is high

[0016] 3) It is difficult to further shrink the pixel: in order to maintain the same signal-to-noise ratio in the charge transmission, the reduction of the CCD unit pixel requires thinning the thickness of Oxide-Nitride (ON), while the reliability requirement of ON is unchanged, so the CCD pixel It is quite difficult to further reduce the

[0019] i) High dark current noise: Since CMOS-APS uses diodes as photosensitive devices, its dark current is almost two orders of magnitude higher than that of CCD

[0020] ii) It is difficult to improve the effective quantum efficiency: Unlike CCD, CMOS-APS contains at least three transistors in addition to the photodiode, and the duty cycle is less than 60%

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