Traditional pressure sensor chips are individually packaged in TO-can or pre-molded housing
format, leading to a low packaging throughput and a large packaging body. This study proposes an
SMD compatible plastic packaging with an opening sensing-channel, producing a tiny body and high
throughput. A photoresist is used to reserve a sensing-channel in the packaging body. According to the
same packaging concept, two packaging approaches using two specific photoresist materials are
designed. One is called sacrifice-replacement approach and the other is called dam-ring approach. In
the sacrifice-replacement approach, a photoresist material is placed just on the top surface of the
silicon membrane in a pressure sensor wafer. It is removed from the packaging body after the plastic
encapsulation process. In contrast, a photoresist material is deposited enclosing the border of the
silicon membrane in a pressure sensor wafer for the dam-ring approach. The deposited photoresist is
one part of the whole packaging body, and is not be removed from the packaging body. The function
of the photoresists is to protect the sensing channel of the pressure sensor packaging from EMC
contamination in a transfer molding process.