An array type optical addressable potential sensor and its manufacturing method

Abstract

The invention discloses an array-type light addressable potentiometric sensor comprising an SOI (Silicon-On-Insulator) substrate and a plurality of isolating islands formed on the SOI substrate, wherein the SOI substrate in the isolating islands is provided with light addressable potentiometric sensing units, a diffusion ring, a substrate electrode and an on-chip reference electrode. The invention further discloses a manufacturing method of the array-type light addressable potentiometric sensor, and the method comprises the steps of: (1) manufacturing the isolating islands; (2) manufacturing the diffusion ring; (3) manufacturing the light addressable potentiometric sensing units; (4) manufacturing the on-chip reference electrode; and (4) manufacturing the substrate electrode. According tothe invention, the degree of isolation between the light addressable potentiometric sensing units are effectively enhanced by adopting the SOI substrate in combination with the isolation channel groove, and the unique design of the on-chip reference electrode in the invention is more favorable for the microminiaturization and integration of the sensor.

Description

Technical field [0001] The invention belongs to the technical field of sensor design, and specifically relates to an array type light addressing potential sensor and a manufacturing method thereof. Background technique [0002] Light Addressable Potential Sensor (LAPS) is a sensor device based on capacitive sensor combined with photoelectric characteristics of semiconductor. Because of its simple preparation process, low packaging requirements, good potential stability, high sensitivity, short response time, and movable light source during measurement, it has caused extensive research and applications. [0003] The sensitive unit of the light-addressable potential sensor has an electrolyte solution-sensitive film-semiconductor structure. When the semiconductor surface of the photo-addressable potential sensor is biased in the depleted state, the light source with adjustable intensity is used to illuminate the silicon wafer, and the photons will excite the silicon material electron...

AI Technical Summary

Problems solved by technology

These methods have inherent defects: polyimide and photoresist will pollute the sensitive unit during the photolithography process, and the photoresist still has the limitation that it cannot be soaked in the solution for a long time. Although there is no corresponding pollution in the thick oxide layer, the The noise suppression effect is not ideal

At the same time, the reference electrode on the current array optical addressable potential sensor basically adopts the traditional larger Ag / AgCl electrode or calomel electrode, which is not conducive to the miniaturization and integration of the array optical addressable potential sensor.

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