The role of antistatic tape in the process of SMT material
The role of antistatic tape in the SMT material receiving process. With the rapid development of electronic component manufacturing technology, in particular, the miniaturization of components and the integration of integrated circuits have continued to increase. use. Its breakdown voltage is usually between 50V and 100V. It has ultra-high-speed, high-frequency IC devices with higher integration and is more sensitive to static electricity. Some VMOS devices have a withstand voltage of only 30V, which puts forward stricter electrostatic protection requirements for the manufacturing process of products containing the above-mentioned electrostatic sensitive devices.
During the production of electronic products, electrostatic discharge can change the characteristics of semiconductor devices, cause damage or unstable performance, and cause damage to the final product or abnormal use. Relevant experts have done statistics. The average product loss due to static electricity is between 8-33%. The harm of anti-static is so great, how to protect electronic products in the production process? Experts believe that the following aspects must be done well:
1. Ground anti-static;
2. Station anti-static connection;
3. The grounding resistance is less than 4ohms;
4. Temperature and humidity control: 20-30 ℃, relative humidity 30-70%;
5. Ionizer, positive and negative ion wind;
6. Human body static protection;
7, packaging using anti-static bags, anti-static boxes, anti-static boxes and so on.
Through years of observation and research on the details of the electronic product process, our company has found out that during the SMT production process, many details of electrostatic protection need to be better. For example: The cover tape of the SMT tape (CoverTaper) does not reach the ideal antistatic impedance (105 ~ 8ohms), the SMT receiving film is not antistatic, the cotton fiber packaging bag is not antistatic, and the steel mesh wiping cloth packaging bag Static electricity and so on ... These phenomena that are not easy to attract attention can be seen everywhere in the production process. The dynamic voltage can be as low as thousands of volts and high as tens of thousands of volts. These phenomena exist Hidden danger of electrostatic breakdown.
In view of these details, we continued to explore and carry out special research. In the second half of 2007, we finally discovered that if the latest domestic advantage project-antistatic tape technology is applied to another traditional advantage project "SMT splice film "The combination of the two will better meet the requirements for electrostatic protection in the electronics manufacturing process. However, during the implementation process, considerable difficulties were encountered. The difficulties themselves are not permanent antistatic, impedance, temperature and humidity effects, and friction resistance (these are the technical advantages of Ke Hongjian), and the biggest difficulty is the use of "SMT film" Adhesive tape. In order to ensure the reliability of SMT non-stop receiving materials, this tape is designed to achieve the highest viscosity. If there is an anti-static coating on the back of the tape, the adhesive surface of the tape can easily migrate the anti-static coating. It is the tape that sticks out of the antistatic coating and affects the stability of the antistatic. From the structural characteristics of antistatic tape (as shown in Figure 1), how to prevent the antistatic coating from being migrated by the adhesive surface? The most important thing is to firmly fix the antistatic coating on the substrate of the tape to form a molecular chain. In response to this technical problem, the research and development team of Kehong will not be afraid of difficulties, give full play to its own technical advantages, combine foreign advanced technology, and after thousands of matching experiments, finally overcome this technical difficulty! In the first half of 2008, the "SMT antistatic material receiving film" (shown in Figure 2) has passed rigorous testing by many well-known companies at home and abroad, such as Huawei and Flextronics, and has reached a dynamic electrostatic voltage <30V (see Figure 3). Up to now, through comparison tests with products in the same industry worldwide, the results show that the product performance of Haiwei Dahang is the best, and the products with the best conditions in terms of various indicators required by the EMS process have become the market segment of this segment. Leader. At present, the products are very mature, stable and available in batches, and are well received by customers. The breakthrough of this technical problem has finally brought about an increase in the yield rate of the electronics manufacturing industry!
With the advent of the information society, electronic products will become more exquisite, reliable and miniaturized, and the requirements for electronic manufacturing processes will be more demanding. Hiway Aviation is willing to work with the majority of science and technology workers in the electronics industry to give full play to its core technology Advantages, pay attention to details, improve problems, overcome technical difficulties in the industry, provide good services, and meet new challenges brought by high-quality and demanding products!