Rotary vacuum pump in semiconductor etching process of practical application
The practical application of rotary vacuum pump in semiconductor etching process is to remove the exposed part of the substrate of photoresist micrograph after exposure and development, that is, to reproduce the same graphics as photoresist on the substrate. Etching is an important step in semiconductor manufacturing, microelectronic IC manufacturing and micro-nano manufacturing. Is associated with lithography graphic processing is a major process. The so-called etching, in a narrow sense, is actually a lithographic etching. First, the photoresist is exposed to photolithography by lithography, and then the required part is removed by etching through other means. With the development of micro-manufacturing technology, in a broad sense, etching has become a general term for stripping and removing materials through solutions, reactive ions or other mechanical means, which has become a universal name for micro-machining.
The process of Si3N4 etching is described below:
Semiconductor etching process for Si3N4 etching:
Etch in 903E etcher, etcher into the gas: CF4, NF3, He. The effect of fluorine free group is to make the silicon nitride corroded, the product is gas, by the vane vacuum pump air pumping away. In order to accelerate the corrosion rate, a small amount of oxygen (5%-8%) can be added to CF4, because oxygen can inhibit the loss of F* in the reaction chamber wall, and: CF4+O2→F* +O*+COF*+COF2+CO+…… (ionization). COF* has a long life. When it moves to the surface of silicon wafer, the following reactions occur to accelerate the corrosion rate: COF*→F* CO (ionization), but more oxygen will corrode photoresist to reduce the selection ratio.
Etching is an important part of micromachining technology. The rapid development of microelectronics pushes it forward. Generally speaking, the etching technology can be divided into dry etching and wet etching. Wet etching is the main etching in the early stage. However, with the device making entering into the age of micron and sub-micron, wet etching is difficult to meet higher and higher precision requirements. Dry etching technology has made great progress. Dry etching is generally used to remove the etched thin film through the combination of physical and chemical methods, so the etching has anisotropy, which can fundamentally improve the inherent problem of horizontal drilling erosion of wet method, so as to meet the requirements of fine line etching. There are a lot of common etching methods, rotary plate vacuum technology is one of them. Semiconductor etching process in rotary vane vacuum pump has carved faster, choice than high, high anisotropy, etching damage small, large area uniformity, good controllability and high etching etching section contour surface level off is smooth, etc, in recent years, the German rotary-vane vacuum pump is widely used in compound materials such as silicon, silicon dioxide, – race of etching, obtained the very good etching effect, can meet the production of very large scale integrated circuit, MEMS devices, optoelectronic devices, such as various kinds of microstructure.
Through rotary vane vacuum pump in the semiconductor etching examples of practical applications of this technology, can reflect with the further understanding of puno g rotary-vane vacuum pump and equipment to further improve, vacuum technology will be more adapt to the request of the diversification of etching, which is increasingly used in the device manufacture craft, become the mainstream of etching technology, improve the preparation of the device from the whole, to further promote the renewal of the components, structure, raising the level of the improvement of the level of integration and better access to a very good effect.