Fabrication method for transistor with composite gate dielectric GaN-based insulating gate and high electron mobility

Abstract

The invention discloses a fabrication method for a transistor with a composite gate dielectric GaN-based insulating gate and high electron mobility, mainly aims to solve the problem of low reliability a similar device. The fabrication method comprises the steps of manufacturing a source electrode, a drain electrode and an electric isolating region of an active region on an epitaxial wafer, and enabling an SiN passivation layer to be grown; photoetching and etching a gate slot region in the SiN passivation layer; enabling an AlN dielectric layer to be grown on the gate slot and the SiN passivation layer, and oxidizing the AlN dielectric layer into an AlON composite gate dielectric layer through thermal oxidization or plasma auxiliary oxidization process; manufacturing a gate electrode on the gate dielectric layer; enabling an SiN protection layer to be grown on the gate electrode and the gate dielectric layer out of the gate electrode region; photoetching and etching a metal interlinked open pore region in the SiN protection layer; and manufacturing a metal interlinking layer on the interlinked open pore region and the unopened and non-etched SiN protection layer to complete the manufacturing of the device. By adoption of the fabrication method, the interface characteristic of the device is improved, the reliability of the device is improved, and the device can be used as an efficient microwave power device.

Description

technical field [0001] The invention belongs to the technical field of semiconductor devices, in particular to a method for manufacturing high electron mobility transistors, which can be used for manufacturing high-frequency and high-power modules. Background technique [0002] Nitride semiconductor materials GaN, AlN, InN and their alloys are the third-generation wide-bandgap semiconductor materials after the first-generation elemental semiconductor materials Si, Ge and the second-generation compound semiconductor materials GaAs, InP, etc., which have a direct bandgap , Wide bandgap width, large continuous adjustable range, high breakdown field strength, fast saturated electron drift speed, high thermal conductivity, and good radiation resistance. With the improvement of technology and social development, the first and second generation semiconductor materials cannot meet the needs of higher frequency and higher power electronic devices. Electronic devices based on nitride ...

AI Technical Summary

Problems solved by technology

However, the surface of nitride materials is very easily oxidized, forming unstable oxygen substitution nitrogen defects in the wurtzite nitride lattice

During the fabrication of insulated gate HEMT devices and the deposition of gate oxide dielectrics, the establishment of a low-quality interface oxide layer causes a high-density interface charge between the gate dielectric layer and the nitride barrier layer, and the charge / discharge effect of the interface state will cause serious threshold Reliability issues such as voltage instability, energy band modulation of interface charges and scattering of remote ionized impurities will cause device performance degradation such as threshold voltage negative drift, channel carrier mobility and transconductance reduction

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