MEMS pressure sensors – new LGA packagings

Cell phone, medical, white goods and other markets are looking for absolute pressure sensors as well as differential pressure sensors. From a customer point of view these two configurations means to have one or two pressure ports, which could require a piping interface if the measured pressure is not the ambient one. For ambient measurement the MEMS LGA module needs only onean hole, which connect the device pressure port with the external environment . ST developed the so-called RHLGA packaging (Reversed Hole LGA), which is made by a flip chip placed on an holed substrates, an epoxy dam connects the pressure die port with the hole, insulating it by the molding compound. This packaging technology allows the reduction of the module dimension close to the die dimensions. Another pressure packaging is based on the integration of the HLGA (Holed HLGA packaging based on die capped and molded with a film assisted molding which leave the pressure port open). This packaging was already presented in the past year-, with a plastic cap with piping connections (one or two) The plastic cap is assembled on the HLGA by means of an epoxy adhesive screened around the pressure holes, which attached and seals the cap.