Corrosion-proof pressure transducer
AssigneeKavlico Corporation
InventorsKyong M. Park, Marcos A. Nassar
Life of this patent
Estimating the term…
Abstract
A corrosion proof pressure transducer for measuring exhaust gas pressure includes a chip with a semiconductive diaphragm, electronics, and conductive pads thereon; with leads sonically bonded to the pads. To preclude degradation of the transducer by internal combustion engine exhaust gases, the chip may have (1) a thin glass passivation layer, (2) a vacuum deposited polymeric coating and (3) a layer of gel, thereon.
Claims13
A corrosion proof pressure transducer system comprising:
- an automobile having an exhaust system;
- a pressure transducer mounted to sense the pressure in said exhaust system;
- said pressure transducer including a chip having a semiconductive diaphragm and conductive pads thereon;
- electrical circuitry mounted on said chip coupled to diaphragm, and said conductive pads;
- wires sonically bonded to said conductive pads;
- said chip having a glass passivation coating thereon;
- said glass passivation coating being in intimate contact with the upper surface of said chip and the circuitry on said chip;
- a vacuum deposited polymeric dielectric coating extending over the glass coated chip including the conductive pads;
- and sealing the upper surface thereof;
- and
- a layer of gel material overlying said chip;
- whereby possible pin holes in the glass coating or cracks in the conductive pads are sealed against the corrosive exhaust gases of said exhaust system.
A corrosion proof pressure transducer system comprising:
- an automobile having an exhaust system;
- a pressure transducer mounted to sense the pressure in said exhaust system;
- said pressure transducer including a chip having a semiconductive diaphragm and conductive pads thereon;
- wires sonically bonded to said conductive pads;
- said chip having a glass passivation coating thereon;
- said glass passivation coating being in intimate contact with the upper surface of said chip and the circuitry on said chip;
- and
- a sealing dielectric coating extending over the glass coated chip including the conductive pads;
- and sealing the upper surface thereof;
- whereby possible pin holes in the glass coating or cracks in the conductive pads are sealed against the corrosive exhaust gases of said exhaust system.
A corrosion proof pressure transducer system comprising:
- a pressure transducer including a chip having a semiconductive diaphragm and conductive pads thereon;
- gel material extending over said chip;
- wires sonically bonded to said conductive pads;
- said chip having a glass passivation coating thereon;
- said glass passivation coating being in intimate contact with the upper surface of said chip and the circuitry on said chip;
- a vacuum deposited polymeric dielectric coating extending over the glass coated chip including the conductive pads;
- and sealing the upper surface thereof;
- whereby possible pin holes in the glass coating or cracks in the conductive pads are sealed against adverse environmental conditions.
A corrosion proof pressure transducer system comprising:
- said pressure transducer including a chip having a flexible diaphragm and conductive pads thereon;
- electrical circuitry mounted on said chip coupled to diaphragm and said conductive pads;
- wires bonded to said conductive pads;
- a sealing polymeric dielectric coating extending over the chip including the conductive pads;
- and sealing the upper surface thereof;
- and
- an additional protective layer overlying said chip;
- whereby said chip is sealed against adverse environmental conditions.
Dependencies are inferred from the claim text.