What is etching technology?

Metal etching, polysilicon etching, oxide etching.

The specific process conditions can not be simply said, these three etches are dry etching in the semiconductor industry, that is, dry etching. The main difference is that all etching gases are different, such as CL2 for metal etching, C4F6 and C5F8 for oxide etching.

The thin film with micropattern structure will remain on the wafer surface. Through the photolithography process, what is finally left on the wafer is the feature pattern part.

Lithography forms various physical elements such as transistors, diodes, capacitors, resistors and metal layers on the wafer surface or surface during wafer manufacturing. These components are produced on one mask layer at a time, and combined with the formation of thin films and the removal of specific parts, parts of feature patterns are finally left on the wafer through photolithography process. The goal of lithography production is to generate characteristic patterns with accurate dimensions according to the requirements of circuit design, with correct position on the wafer surface and correct association with other parts.

Lithography is the most critical of all four basic processes. The key dimensions of the device are determined by lithography technology. Errors in the lithography process will lead to pattern distortion or poor registration, which will eventually turn into an impact on the electrical characteristics of the device. Graphic dislocation can also lead to similar bad results. Another problem in lithography process is defects. Lithography is a high-tech version of photography, but it is done on a very small size. Contaminants in the process can lead to defects. In fact, because lithography needs to complete 5 to 20 or more layers in the wafer production process, the pollution problem will be amplified.

working procedure

Generally, the lithography process involves cleaning and drying the surface of silicon wafer, priming, spin-coating photoresist, soft baking, alignment exposure, post-baking, development, hard baking, etching and detection.