Reference electrode-free GaN-based pH sensor based on groove structure and manufacturing method thereof

Abstract

The invention relates to the technical field of semiconductor pH sensors, and relates to a reference electrode-free GaN-based pH sensor based on a groove structure and a manufacturing method thereof.The method comprises the following steps: a thin-layer low-Al component AlGaN barrier layer and an AlN insertion layer firstly grow on a GaN epitaxial material, a layer of dielectric layer is deposited on the surface of the material as a mask layer, a photoetching developing technology and wet etching are adopted to remove the dielectric layer outside a detection area, patterning of the mask layeris realized, a high-Al component AlGaN thin barrier layer further grows on a mask-free area to form a groove structure, a detection material sensitive to pH changes is deposited in the groove area, an ohmic contact electrode is manufactured, and an area outside the groove is finally packaged to form a sensing device. The process is simple, while the thin-layer low-Al component AlGaN in the groovearea keeps a two-dimensional electronic airway, the transconductance of the device is effectively enhanced, the high-Al component AlGaN in an access area can form a high-concentration two-dimensionalelectronic device to reduce the sensor loss and enhance the sensor reaction speed.

Description

technical field [0001] The invention relates to the technical field of semiconductor pH sensors, in particular to a GaN-based pH sensor without a reference electrode based on a groove structure and a preparation method thereof. Background technique [0002] The pH sensor is an essential inspection device for measuring the pH of liquid media, precise monitoring and scientific certification. It has important applications in the fields of environmental, medical, industrial, agricultural and biological solutions. With the continuous development of science and technology, the all-solid-state pH sensor based on Ion Sensitive Field Effect Transistor (ISFET: Ion Sensitive Field Effect Transistor) has been favored for its small size, non-fragile, high sensitivity, stable performance, and portability. favor. At present, Si-based MOSFET has become the main material for the preparation of ISFET pH sensors due to its low price, mass production compatibility with traditional CMOS process...

AI Technical Summary

Problems solved by technology

[0005] (2) Materials that are sensitive to pH changes are generally amphoteric metal oxides, and heterogeneous epitaxy needs to be carried out by physical or chemical vapor deposition. During the preparation process, it is very easy to introdu

Images