Chip scale packaging of piezoresistive pressure sensors using the dry-film shielding

In this study, chip scale packaging (CSP) for piezoresistive pressure sensors using a dry-film shielding approach is demonstrated. Experimental results reveal that the silicon membrane of the pressure sensor is free of metal-deposition contamination and functionally operational. The packaged pressure sensor met all of the specifications of an unpackaged bare pressure sensor, holding a maximum sensing error of 0.18 psi over an operation temperature range of 25~85degC. The proposed pressure sensor packaging has advantages on both low cost and tiny packaging size, making it suitable for portable consumer products.