TiN film layer morphology etching method and TiN film layer

Abstract

The invention belongs to the technical field of semiconductor integrated circuits, and particularly relates to a TiN film morphology etching method and a TiN film. The method comprises the following steps: firstly, etching a silicon oxide film layer in a to-be-etched film layer by taking photoresist as a mask to enable the silicon oxide film layer to be in a regular splayed shape; etching the TiN film layer in the to-be-etched film layer by taking the silicon oxide film in the regular splayed shape as a mask, so that the TiN film layer is in the regular splayed shape; furthermore, the TiN film layer in a regular splayed shape is laterally corroded by adopting a wet method, so that the TiN film layer is in a regular trapezoidal shape, and the inner included angle between the side surface of the TiN film layer and the top surface of the P-gallium nitride is between 85 degrees and 90 degrees; and after the silicon oxide film is stripped off, a film layer with the target TiN morphology is obtained. According to the TiN film layer prepared through the method, the contact area of the TiN layer and the p-GaN layer is large, the electric leakage situation of a reverse schottky junction composed of the TiN layer and p-GaN can be reduced, and it is guaranteed that the TiN film layer has large turn-on voltage and high anti-noise capacity.

Description

technical field [0001] The application belongs to the technical field of semiconductor integrated circuits, and in particular relates to an etching method for the morphology of a TiN film and a TiN film. Background technique [0002] High Electron Mobility Transistor (HEMT) is a common device in microwave radio frequency, optoelectronics, power electronics and other fields. [0003] There are various types of HEMTs, including GaN-based HEMTs. The gate structure (ie, HEMTGate) of a GaN-based HEMT generally includes a TiN film layer, a GaN gate and a Si substrate. Among them, the GaN Gate includes p-GaN (p-type gallium nitride) / Al-GaN / GaN. In the HEMT Gate, TiN can form a reverse Schottky junction of metal and semiconductor with p-GaN, thereby improving the turn-on voltage and anti-noise capability of the HEMT Gate. In this reverse Schottky junction, the unilateral distance between the TiN layer and the p-GaN layer is 400+ / -100 angstroms. [0004] At present, when the abov...

AI Technical Summary

Problems solved by technology

[0005] In view of this, the embodiment of the present application provides an etching method for the morphology of the TiN film layer and the TiN film layer, so as to solve the problem in the prior art that the TiN layer and the p- The contact area of ​​the GaN layer is small, which increases the leakage of the reverse Schottky junction formed by TiN and p-GaN, thus affecting the turn-on voltage and noise resistance of the Schottky junction.

Images