Since the beginning of 2020, due to the impact of global epidemic situation, the supply and demand chain of raw materials for copper clad laminates in China has undergone important changes; at the same time, 5g has also made great changes in the technology, performance and variety of CCL for high-frequency and high-speed circuit, and substrate materials for high-speed HDI and IC packaging carriers. The two changes have become an urgent task to study the supply chain pattern of electronic copper foil, special resin and special glass fiber cloth used in new and high-end substrate materials and the new performance requirements of materials.

Electrolytic copper foil
Supply status and market characteristics of various low profile electrolytic copper foil
The scale and layout of the global high-frequency high-speed electrolytic copper foil market in 2019 (market share of each country / region and major manufacturers) are shown in Figure 1 and table 1.
Figure 1 scale and pattern of global low profile copper foil market in 2019
Table 1 Statistics and forecast of market structure of low profile copper foil for high frequency and high speed circuit in 2018 and 2019
Global low profile copper foil production and sales (i.e. market size) is estimated to increase by 49.8% to 53000 tons in 2019. It is estimated that it accounts for 7.6% of the total electrolytic copper foil in the world. In the global production and sales of HF high-speed electrolytic copper foil in 2019, the ratio of RTF to VLP + HVLP is about 77:23. But the proportion of VLP + HVLP will increase in the next few years.
In 2019, domestic and foreign copper foil enterprises in Chinese mainland produced a total of 7580 tons of low profile copper foil, of which domestic enterprises accounted for 51.2% (3880 tons). The production and sales volume of low profile electrolytic copper foil of domestic enterprises accounted for 2.7% of the total domestic enterprises' output of electronic circuit copper foil (144000 tons). In 2019, domestic enterprises will achieve a new breakthrough in mass production of VLP + HVLP varieties, but the production and sales of such low profile copper foil are very few, accounting for only 2.3% of the global total production and sales of such electrolytic copper foil.
Special resin
Requirement of special resin for high frequency and high speed copper clad laminate
There are two main resin composition process routes for high frequency and high speed circuit copper clad laminates with low loss grade (DF ≤ 0.008): one is composed of thermoplastic resin system represented by PTFE; the other is thermosetting resin system represented by hydrocarbon resin or modified polyphenylene oxide resin.
In the second process route composed of thermosetting resin system, PPO as the main body + crosslinking agent (the crosslinking agent can be bismaleimide resin, Triallyl triisocyanate (TAIC), hydrocarbon resin, etc.) is the main route. At the same time, the resin composition design technology for high-frequency and high-speed circuit has been continuously promoted and diversified in recent years. The process route of modified maleimide (bifunctional and multi-functional group type) as the main resin, the very low loss grade composed of special epoxy resin (dicyclopentadiene type, diphenyl ether type, etc.) and Benzoxazine Resin process route, as well as the copper clad laminate (CCL) for high frequency and high-speed circuit under very low loss level.
The statistics of resin types used for CCL with different signal transmission loss levels are shown in Fig. 3. Table 3 summarizes the key resin materials for high frequency and high speed copper clad laminates and their main suppliers at home and abroad.
Fig. 3 types of resins used for simultaneous interpreting of high frequency and high speed copper clad laminate with different transmission loss levels
Table 3 key resin materials for high frequency and high speed copper clad laminates and their main suppliers at home and abroad
Chinese manufacturers of PTFE stock solution for PTFE type CCL include Chenguang (Sichuan), Dongyue, Juhua, Chenguang kemufu materials (Shanghai) Co., Ltd. (a joint venture between Chenguang and DuPont), sanaifu, etc. In addition, Jiangxi fluoride is also under construction. The domestic production of PTFE solution for CCL is estimated to account for more than 60% of the global total.
Modified polyphenylene oxide resin (PPO / PPE) as the substrate material of main resin has an irreplaceable role in the field of very low loss corresponding to 5g communication equipment. Most of its terminal products are servers of base station facilities. With the development of 5g communication, the demand for PPO / PPE is also expanding rapidly. China Guangdong Tongyu has mass production, Shandong Shengquan, Dongcai technology has entered the customer trial, evaluation stage.
Hydrocarbon resin in the development of high-frequency and high-speed copper clad laminate, whether in variety, technology, or the breadth of application, scale, have been rapid development in the substrate material industry. Hydrocarbon resin and maleimide (long chain) are also used in the manufacture of high-end HDI board, packaging carrier plate and module substrate made by semi addition method. China is still a short board in terms of innovative development, mass production and application of hydrocarbon resin, which needs to catch up.
It should be noted that the global flexible substrate materials, as well as the emerging resin film for PCB, have significant changes in resin materials. The domestic resin enterprises supporting the copper clad laminate industry should adapt to the new requirements of these two types of substrate materials, such as LCP crystalline polymer, MPI (modified polyimide) resin, new TPI resin, modified bismaleimide resin (modified BMI), special epoxy resin (phenoxy resin, etc.).
Special glass fiber cloth
In the world and China's copper clad laminate industry, there are two hot demands for glass fiber cloth as reinforcement materials. One is ultra-thin or extremely thin glass fiber cloth; the other is low DK electronic glass fiber cloth. Such two hot varieties, the main market in high-frequency high-speed copper clad laminates.
Performance requirements for ultra-thin or ultra-thin glass fiber cloth
The use of ultra-thin glass fiber cloth has become a trend: Nowadays, electronic cloth such as 1067 mm (0.035 mm), 106 mm (0.033 mm), 1037 mm (0.027 mm) has been widely used