Production process for Schottky chip

Abstract

The invention discloses production process for a Schottky chip, which comprises the following steps of: providing an original epitaxial silicon chip; oxidizing the original epitaxial silicon chip to form an oxidized layer; carrying out first-time photoetching; carrying out P-ring diffusion; carrying out second-time photoetching on ditch grooves, carrying out first-time etching; carrying out third-time photoetching to remove oxidized layers on intervals of the ditch grooves; carrying out second-time etching; sputtering metals, i.e., Pt and Ni, on a frontal face; evaporating metals, i.e., Ti, Ni and Ag, in contact with the frontal face; photoetching metals; thinning a back face; and evaporating metals, i.e., Ti, Ni and Ag, in contact with the back face to obtain a product. The invention further discloses an etching solution used in the production process for the Schottky chip, which comprises the ingredients of HF, HAC, H2O2 and HNO3. With the adoption of the production process for the Schottky chip, smooth ditch grooves with depth of 1.0 micron and accuracy of + / -0.15 microns can be obtained, and the surface area of silicon is approximately enlarged by over 20%, thus the working efficiency is increased by approximately 20% for a same chip area with the adoption of the invention, and a substantial base is laid for batch production of the Schottky chips.

Description

technical field [0001] The invention relates to a production process of a silicon body chip and an etching solution, in particular to a production process of a Schottky chip and an etching solution used in the production process, and belongs to the production field of the Schottky chip. Background technique [0002] According to the semiconductor principle, Schottky (SKY) belongs to the surface semiconductor device, so increasing the surface area will inevitably increase its work efficiency and improve its effectiveness. Therefore, it has been researched and discussed internationally for many years. ICP (reactive ion etching, a Gas dry etching of silicon) to etch the groove structure on the surface of silicon. The advantages of this technology are good controllability, good uniformity (up to a depth of 1um, and an accuracy of ±0.1um). The disadvantage is that the equipment is expensive and the corrosion The exhaust gas produced is very polluting to the air, requiring large i...

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Problems solved by technology

[0002] According to the semiconductor principle, Schottky (SKY) belongs to the surface semiconductor device, so increasing the surface area will inevitably increase its work efficiency and improve its effectiveness. Therefore, it has been researched and discussed internationally for many years. ICP (reactive ion etching, a Gas dry etching of silicon) to etch the groove structure on the surface of silicon. The advantages of this technology are good controllability, good uniformity (up to a depth of 1um, and an accuracy of ±0.1um). The disadvantage is that the equipment is expensive and the corrosion The exhaust gas produced is very polluting to the air, requiring large investment and strict exhaust gas treatment

The traditional wet acid etching process, due to its corrosiveness and process heating reaction, has not been greatly developed and improved for many years. It is mainly used for product applications with a corrosion depth of 50-150um, and its accuracy is controlled at ±10um. Rough, cannot be used for surface devices like Schottky at all

In addition, the corrosion accuracy of the etching solution used in the wet acid etching process for the production of Schottky chips is obviously low, which cannot meet the high precision requirements of Schottky chips

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