Investigation of the Features of Metallization Formation for N-MOS Transistor Structures with a Vertical Channel

Abstract—

This paper examines the features of the metallization unit of a power transistor with a vertical channel. It consists of alternating layers based on depth and includes titanium, titanium nitride and tungsten. Thick-film aluminum wiring is placed on the surface of the silicon substrate. Based on Auger spectroscopy and analysis of transmission electron diffraction patterns, it was revealed that a titanium dislicide film in the C₅₄ phase is formed using low-temperature heat treatment and subsequent high-temperature annealing. It is shown that the introduction of special cyclic plasma treatment after deposition of a layer of titanium nitride using the metal-organic chemical vapor deposition method (MOCVD) made it possible to reduce the resistance of the films and reduce the level of mechanical stress. It has been shown that the addition of rhenium, titanium and nitrogen in the range of 5–10 at % allows you to reduce the mechanical stress of the tungsten layer by 3–5 times. Depending on the method of deposition of tungsten (magnetron or chemical), we have proposed two design options for this unit. A method for forming aluminum wiring based on thick-film aluminum using a sacrificial layer of titanium nitride is proposed. The proposed solutions provide the opportunity to improve the electrical and mechanical properties of the metallization unit of MIS transistor structures with a vertical channel.