Wafer and Wafer Adhesion Thickness:
The wafer adhesion is generally quite thick (1mm or more), but the packaging market for standard ICs is now facing a multidimensional development, which poses a significant challenge to the packaging technology because some traditional assembly equipment cannot be used. There is also no standardized tool.
The wafer cutting process is the biggest problem. With viscose carrier tape for manual operation, water flow and vibration can destroy micro-surface micro-mechanical structures. In addition, cutting before the sacrificial layer is etched adds cost. Since the MOEMS first-level package does not have to be in contact with the surrounding environment, this problem can be solved. Thermal Control: Thermal fluctuations can cause performance instability, and materials with different CTEs can cause light to be off-axis, thus requiring thermal control in the chip and package. Radiators such as thermal regulators can be used for cooling to maintain a constant temperature. Chip placement is a silver material filled with epoxy or epoxy resin with high thermal conductivity.
The mechanically or thermally generated stress in a PCB design MOEMS device is related to its working principle. One problem that is believed to be caused by functional problems and mismatch losses can reduce reliability and performance, often caused by the slow shrinkage of the adhesive or epoxy that connects the silicon chip to the package.
Hermetically sealed devices:
Hermetically sealed devices are often used to increase the long-term reliability of the device. Vacuum or inert gas is generally evacuated to prevent moisture, moisture, and contamination from entering the enclosure or eroding the environment. The metal, ceramic, silicon, or millimeter-thick glass must be used to make the hermetically sealed envelope. The electrical and optical interconnections must be hermetically sealed.
Due to small deviations in the manufacturing process, PCB design MOEMS devices must be tested to meet the required technical specifications. One is to use laser trimming resistors or laser ablation methods, and the other is to use electronic compensation methods.