Hardware Development Guide of Module Product
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8
Manufacturing Guide
8.1
Design of Steel Mesh
During the design of steel mesh, note:
1. When manufacturing the steel mesh of thermal pad on the bottom of the
module, narrow the mouth of the steel mesh to 75% of the original size, so as
to reduce the risk of shortcut between the module thermal and the peripheral
PINs. This method is effective.
2. It is recommended to design to the mouth of steel mesh on the thermal pad
wielding panel to the lattice form. Figure 8-1 shows the recommended pattern
for the steel mesh.
Figure 8-1 Recommended Pattern of Steel Mesh on Wielding panel
8.2
Furnace Temperature Curve
The furnace temperature curve greatly affects the wielding quality and the material
status, so it needs to be paid great attention to. The temperature increasing speed
cannot be too fast, with the increase speed from the room temperature to 150
℃
less than 3
℃
/second. At the same time, if the temperature is above 217
℃
, the
duration should be kept within 70 seconds, while the interim value 55 seconds is
ideal. Otherwise, the great temperature shock will make certain devices ineffective,
causing the quality to decrease and the maintenance difficulty to increase. At the
same, keep the precise maximum temperature to be below 245
℃
, as certain
materials (such as the crystal) might crack under the high temperature and won’t not
vibrate any more, so the product function is affected. Refer to Table 8-1 for the
setting of furnace temperature curve, refer to Figure 8-2 for the furnace temperature
