Manufacture of pressure sensor by injection molding over semiconductor mounting assembly and lead frame with clearance, employs plunger locally controlling temperature of duroplastic mass

摘要

A plunger (43), in the injection mold (40) leaves clearance (45) from the side of the mounting section (12) opposite the semiconductor pressure receiver (2). Alternatively the gap is formed with the side of the receiver facing away from the mounting section. The temperature of the plunger (43) is altered relative to that of the injected liquid mass, to cause a reduction in fluidity close to the plunger. This inhibits penetration of the mass into the gap (45). Preferred features: Cooling the plunger raises the viscosity, causing incomplete penetration into the gap. Heating the plunger accelerates cross-linking and hardening near the plunger, preventing complete penetration of the gap by the mass.