China's semiconductor equipment enters the era of "big purge"

Release time:

2023-12-01 15:22

Author: Chang Qiu

 

The semiconductor cleaning equipment market is dominated by international giants, and Chinese manufacturers are catching up.

 

Last week, another important piece of information came from China’s semiconductor equipment market. Local cleaning equipment manufacturer Ame Shanghai launched a new type of post-chemical mechanical polishing (Post-CMP) cleaning equipment. This is the company’s first Post-CMP cleaning equipment. Used for cleaning after chemical mechanical polishing processes to produce high quality substrates. The 6-inch and 8-inch configurations of the cleaning equipment are suitable for silicon carbide (SiC) substrate manufacturing; the 8-inch and 12-inch configurations are suitable for silicon wafer manufacturing.

 

After the CMP step, a physical pre-cleaning process using dilute chemicals at low temperatures is required to reduce the particle count. Post-CMP cleaning equipment can meet these requirements.

 

Among the various front-end semiconductor equipment used for wafer processing, the localization rate of cleaning equipment used in the Chinese market is still relatively high, reaching 38%, second only to the 74% of glue removal equipment. With a market share of 38%, it not only has a certain scale but also has relatively large room for development. It is a category worthy of attention.

 

The importance of cleaning processes
 

In all aspects of wafer processing, the cleaning process is essential. It is mainly used to remove ultrafine particle contaminants, metal residues, organic residues, and photoresist mask residues left over from the previous process during wafer processing. It can also be used Wet etching of thin film materials such as silicon oxide film, silicon nitride or metal is carried out as needed to prepare the wafer surface conditions for the next step.

 

According to different media, semiconductor cleaning technology is mainly divided into two categories: dry cleaning and wet cleaning. At present, wet cleaning is the mainstream, accounting for more than 90% of the total number of cleaning steps. Wet cleaning uses specific chemical liquids and deionized water to clean the wafer surface non-damagingly according to different process requirements to remove the wafer. Impurities in the manufacturing process are often supplemented by ultrasonic, heating, vacuum and other technical means. Dry cleaning refers to a cleaning technology that does not use chemical solvents. The pollutants that can be cleaned are relatively single. It is used in the manufacturing process of logic and memory chips with 28nm and above process technologies.

 

Differences in process technology and application conditions make cleaning equipment on the market significantly different. Currently, the main cleaning equipment includes single wafer cleaning equipment, automatic cleaning tables and scrubbers. Other cleaning equipment also includes ultrasonic/megasonic cleaning equipment. , wafer box cleaning equipment, dry cleaning equipment (such as plasma cleaning equipment), etc., but the market share of these equipment is relatively small.

 

With the development of large-scale integrated circuits, the importance of cleaning during wafer processing has become increasingly prominent, and precision requirements are getting higher and higher. When the process technology node is 35nm, the parameter requirements are already high, and it is necessary to ensure that the particle and COP density on the surface of the silicon wafer is less than 0.1 particles per square centimeter. The current advanced process nodes are below 5nm, which puts forward higher cleaning parameter requirements for wafers. In addition, economic benefits also require semiconductor companies to make continuous breakthroughs in cleaning processes and improve the parameter level of cleaning equipment. As process nodes continue to shrink, effective non-destructive cleaning will be a major challenge for manufacturers seeking advanced process chip production solutions, especially for chips with 7nm, 5nm or even smaller process nodes. Wafer fabs must be able to Removing smaller random defects from a flat wafer surface also requires adapting to more complex and sophisticated 3D chip architectures to avoid damage or material loss, thereby ensuring yield and profit.

 

As process nodes continue to shrink, during wafer processing, the yield rate decreases as the line width shrinks. One way to improve the yield rate is to increase the steps of the cleaning process. In the 80nm-60nm process, there are about 100 cleaning steps, but in the advanced processes of 20nm and beyond, the number of cleaning steps rises to more than 200.

 

Giants dominate the market
 

Cleaning equipment accounts for approximately 5% of the total semiconductor equipment market. In 2021, the cleaning equipment market will grow rapidly, with the market size reaching US$4.2 billion, and it is expected to reach US$4.7 billion in 2022.

 

For a long time, the global cleaning equipment market has been dominated by SCREEN, TEL, LAM and SEMES (a subsidiary of Samsung). The total market share of these four companies has reached more than 90%. Among them, SCREEN The taxi market share is the highest, exceeding 50%. Over the years, Deans has developed various types of cleaning equipment suitable for a variety of environments, and has gained the first market share in the three main areas of cleaning technology. After 2014, Shengmei Company also entered this field and occupied a smaller market share.

 

Since the technical threshold for automatic cleaning tables is relatively low, there are more market participants, but the market share is firmly controlled by Deans and Tokyo Electronics. Washing machine equipment is basically dominated by two companies, Deans and Tokyo Electronics, with Deans accounting for 60%-70%.

 

Deans' market leadership position stems from its technical barriers. The company has always led the most advanced cleaning technology. Taking single wafer cleaning equipment as an example, Deans continues to achieve technological improvements and breakthroughs, and develops new cleaning equipment products, from SU-2000, SU-3100 to SU-3200, and then to SU-3300, constantly pursuing greater success. wafer cleaning capacity while effectively reducing fab costs. SU-3200 can integrate 12 chambers, with a processing capacity of 800 wafers per hour, while SS-3300 can integrate 24 chambers, with higher processing capacity, effectively solving the shortcomings of low productivity of single wafer cleaning equipment and giving full play to Excellent cleaning performance, in line with 10nm and 7nm cleaning parameter requirements. Especially in the field of memory chips, as DRAM manufacturers pursue smaller process nodes and continue to increase investment in 3D-NAND production lines, the SU-3300 can provide refined cleaning technology while achieving a production capacity close to that of an automatic cleaning station.

 

Deans believes that the future development of cleaning equipment will focus on three aspects: first, the expansion of production lines as wafer foundries and logic chip factories continue to deploy smaller process nodes, focusing on high-precision single-wafer cleaning equipment; second, It is a 3D structure memory chip, focusing on high-capacity single wafer cleaning equipment and high-precision automatic cleaning tables; third, it attaches great importance to the Chinese market, which will be the home of the future semiconductor world.

 

The rise of local Chinese manufacturers
 

China's semiconductor market is vast, and cleaning equipment has good development prospects here. Although international semiconductor equipment giants occupy most of the market share, local Chinese manufacturers also perform well.

 

Currently, there are three domestic manufacturers that can provide mid-to-high-end wet cleaning equipment, namely Zhichun Technology, Northern Huachuang and Shengmei, and the market share of domestic manufacturers is still increasing year by year. Compared with other semiconductor equipment, the technical threshold of cleaning equipment is lower, and it is expected to be the first to achieve full localization in the next five years.

 

In terms of products, local companies also have their own strengths. Shengmei Shanghai's single-chip cleaning equipment, fully automatic trough cleaning equipment, single-chip trough combination cleaning equipment, and TEBO megasonic cleaning equipment are very distinctive. As of October 2021, the company's wet method equipment has delivered 2,000 cavities, with a cumulative output of More than 300 units have been shipped; North Huachuang mainly produces single-chip cleaning equipment and fully automatic trough cleaning equipment; Zhichun Technology is good at single-chip cleaning equipment and trough cleaning equipment. The company's single-chip wet equipment is a rotating spray Spin- Spray type, benchmarked against companies such as Deans and LAM. As of the third quarter of 2021, Zhichun Technology has delivered more than 100 units of wet method equipment. Its customers include SMIC Ningbo, SMIC Shaoxing, SMIC Tianjin, Huawei, and Yandong Microelectronics, Shanghai Integrated Circuit R&D Center, Power Semiconductor, etc.; Xinyuan Micro is also a rising semiconductor equipment company in China. The company's single-chip cleaning equipment and fully automatic SCRUBBER cleaning equipment are very distinctive.

 

Products and related technologies of Chinese cleaning equipment companies (Source: Oriental Securities Research Institute)

 

The rise of Chinese cleaning equipment manufacturers has provided more support to local fabs. Data shows that major domestic chip manufacturers, such as Yangtze Memory, Huali Integration, Huahong, etc., are increasingly using products produced by local manufacturers. Cleaning equipment.

 

According to statistics from CITIC Securities, in Yangtze Storage’s cleaning equipment bidding from 2017 to 2022, Amei Shanghai’s number of winning equipment bids was second only to Deans. The winning domestic manufacturers also included Northern Huachuang, Yitang Technology, and Core Silicon Technology. Shengmei Shanghai won the bid for a total of 35 units, mainly including various single-chip cleaning machines. Northern Huachuang won the bid for two process block etching and recovery cleaning machines. Yitang Technology won the bid for two cleaning equipment in 2021. Core Silicon Technology won the bid. 5 parts cleaning machines.

 

From 2017 to 2022, among the cleaning equipment purchased by Huali Integration, Shengmei Shanghai won the bid for a total of 19 units, including front-end and back-end process cleaning equipment, second only to Deans in number, and Northern Huachuang won the bid for 13 units, both For parts cleaning equipment, Xinyuan Micro won the bid for 3 brush cleaning equipment.

 

Between 2017 and 2022, among the cleaning equipment purchased by Huahong Wuxi, Deans and Shengmei Shanghai ranked the top two. Among them, Shengmei won the bid for 24 units, including front and rear processes, involving copper wire polymer stripping, aluminum wire And through-hole cleaning, polysilicon oxide film wafer regeneration, diffusion furnace cleaning and other links. Another domestic manufacturer, Shanghai Jiyi, won the bid for Huahong Wuxi cleaning equipment for the first time in September 2021. It is a 12-inch sheet plasma back cleaning machine.

 

Judging from the cumulative bidding status of the three fabs, Yangtze Memory, Huali Integration, and Hua Hong Wuxi, the total number of domestic cleaning equipment winning bids reached 114 units, and the total number of wafer fab bidding equipment was 301 units. From this calculation, the localization rate is approximately 37.8% .

 

However, the current domestic cleaning equipment is still mainly used in back-end processes, and some of it is used to process control films and blanks. However, there are few domestically produced equipment used in the front-end processes of film and wafer fabs. This is a shortcoming, but it is also an opportunity. There is a lot of room for development in the future.