Semiconductor equipment series. Mask aligners.

Semiconductor Equipment Series-mask aligner is the "crown" of the semiconductor industry.

1, principle

Lithography refers to the fine processing technology that the photoresist changes chemically under the action of light or electron beam with a specific wavelength, and then the pattern designed on the mask is transferred to the substrate through subsequent processes such as exposure, development and etching. As a light source, a laser emits a light beam. After the light path is adjusted, the light beam passes through the mask and lens, and the optical error is compensated by the objective lens. The pattern is exposed on the silicon wafer with photoresist and then developed on the silicon wafer.

2. Development process

So far, mask aligner has gone through five product iterations. Before 1985, the first generation mask aligner light source was mainly a 436nm G-ray mercury lamp, which was only suitable for processes above 5μm; Then, the second generation mask aligner of 365nm i-ray mercury lamp light source appeared, and the process accuracy reached 350-500nm. In the third generation scanning projection mask aligner, the light source was improved to 248nm KrF excimer deep ultraviolet light source, which achieved a leap-forward development and pushed the minimum process to 150-250 nm.

The fourth marching projection mask aligner uses ArF argon fluoride excimer laser source with wavelength of 193nm, which can advance the manufacturing process to 65- 130 nm. The fifth generation EUV mask aligner has chosen a new scheme to further provide a shorter wavelength light source.

3. Market

At present, the global mask aligner market is monopolized by ASML in the Netherlands, Canon and Nikon in Japan, so the statistics of the three companies can represent the whole industry. At present, China also has its own mask aligner, but there is a big gap with foreign leading technologies. Through active research and development, Shanghai Microelectronics Equipment Co., Ltd. (SMEE) has realized the mass production of 90nm node mask aligner, and adopted ArF light source, which can meet the requirements of 90nm and above processes. Domestic mask aligner is seeking the breakthrough of the next technology node.

4. Industrial chain

Mask aligner industrial chain mainly includes three links: upstream core components and supporting equipment, midstream production in mask aligner and downstream application in mask aligner. Mask aligner's technology is extremely complex, which is the highest in all semiconductor manufacturing equipment.

5. Positioning of the mask aligner.

After Huawei was restricted by American chips, localization in mask aligner became a hot topic. However, the localization of mask aligner cannot be accomplished overnight. Mask aligner is a very complicated system and a collection of various sophisticated technologies. Almost every segment needs the cooperation of the top suppliers in the industry. It is impossible for one or two companies to finish mask aligner R&D behind closed doors.

A number of outstanding domestic enterprises have emerged in mask aligner's core components and supporting facilities, including two-level manufacturer Huazhuo Jingke, light source system manufacturer Fu Jeer Science and Technology, Nanda Optoelectronics, Rong Da Photosensitive, etc. Although "the road is long and Xiu Yuan is awkward", many parts and raw materials in mask aligner are stuck in the neck; However, "the line will come soon". By constantly cultivating talents and improving the industrial chain, I believe that one day a breakthrough can be achieved!