Partner

全部分类

Home page

Live full press: control of multilayer PCB laminating parameters

Published:

2022-11-23 14:58

Live full press：Control of Laminating Parameters of Multilayer PCB

1. There are several important temperature parameters in the process of temperature and lamination. That is, the melting temperature of the resin, the curing temperature of the resin, the set temperature of the hot disk, the actual temperature of the material and the change of the heating rate. It is precisely because of the further increase in temperature that the resin further melts and starts to flow. During the period of 70-140 ℃, the resin is easy to flow. It is precisely because of the fluidity of the resin that the resin can be filled with glue and wetted. With the temperature rising gradually, the fluidity of the resin experienced a process from small to large, then to small, and finally when the temperature reached 160-170 ℃, the fluidity of the resin was 0. In order to make the resin better filled and wetted, it is important to control the heating rate. The heating rate is the embodiment of the laminating temperature, that is, to control when and how high the temperature rises. The control of heating rate is an important parameter for the laminating quality of multilayer PCB boards. The heating rate is generally controlled at 2-4 ℃/MIN. The heating rate is closely related to different types and quantities of PP. For 7628PP, the heating rate can be faster, that is, 2-4 ℃/min; for 1080 and 2116PP, the heating rate can be controlled at 1.5-2 ℃/min. At the same time, there is a large amount of PP, and the heating rate cannot be too fast, because the heating rate is too fast, the wettability of PP is poor, the resin fluidity is large, and the time is short, which is easy to cause sliding plates and affect the laminating quality. The temperature of hot plate mainly depends on the heat transfer of steel plate, steel plate and kraft paper, which is generally 180-200 ℃.

2. The pressure and the laminating pressure of multilayer PCB board are based on the basic principle that whether the resin can fill the interlayer cavity and exhaust the interlayer gas and volatile matter. As the hot press is divided into non vacuum press and vacuum hot press, there is a section of pressurization starting from the pressure. Two stage pressurization and multi stage pressurization. General pressurization and two-stage pressurization are adopted for general non vacuum press. The vacuum pumping unit adopts two-stage pressurization and multistage pressurization. Multi section pressurization is usually used for high, fine and thin multilayer PCB boards. The pressure is generally determined according to the pressure parameters provided by P P suppliers, generally 15-35kg/cm2.

3. The time and time parameters are mainly the control of lamination pressure time, temperature rise time, gel time, etc. For two-stage lamination and multi-stage lamination, control the timing of main pressure. If the main pressure is applied too early, it will lead to too much resin extrusion and glue flow, resulting in insufficient glue in the laminate, thin plate, or even sliding plate. If the main pressure is applied too late, it will cause defects such as insecure bonding interface, cavities, or bubbles.

Therefore, how to determine the laminating temperature, pressure, and time software parameters is the key technology for multilayer PCB laminating processing. According to years of practical experience in laminating, it is believed that the most ideal "temperature, pressure, and time" software parameters can be determined only when the laminating software parameters "temperature, pressure, and time" are organically matched. However, the "temperature, pressure and time" parameters can be determined according to different PP combination structures, different PP suppliers, different PP models, and different PP characteristics.

More technical information: http://www.szvstar.cn