Patent ID: 8161811
Filing Date: 2012-04-24
Classification: G01F,H01L,Y10T

Abstract:
1. A corrosion resistant flow sensor apparatus, comprising: a package substrate having a package substrate surface including a plurality of substrate bond pads thereon; at least one flow sensor die comprising silicon mounted on said package substrate surface including a sensing structure for sensing a mass flow parameter from a medium flowing over said sensing structure and a plurality of sensor bond pads coupled to said sensing structure for providing a sensing signal, wherein said sensor bond pads comprise a top metal layer disposed on a metal diffusion barrier layer including a metal diffusion barrier layer sidewall; bond wires for coupling said plurality of sensor bond pads to said substrate bond pads; a housing comprising plastic formed around said sensor die and said sensor bond wires comprising sides and a top portion, wherein said housing includes a flow channel having an inlet for providing said medium flowing over said sensing structure and an outlet; a multi-layer corrosion protection coating comprising a nanometer-scale adhesion layer and a self assembled monolayer (SAM) that is hydrophobic or hydrophilic disposed on said adhesion layer, wherein said multi-layer corrosion protection coats said sensor bond pads including over said metal diffusion barrier layer sidewall and coats said sensor bond wires, and a signal processing circuit on said substrate surface that receives and processes said sensing signal from said sensing structure.