Method for forming micromachined liquid flow sensor
US10908006B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 2019 |
| Grant date | Feb 2, 2021 |
| Priority date | — |
| Expiry date | Aug 29, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/6847
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The micromachined liquid flow sensor devices are enclosed with silicon nitride film as passivation layer to protect device from penetration of liquid into device and avoid the damages of erosion or short circuit etc. One thin layer of silicon dioxide is deposited underneath the silicon nitride layer to enhance the adhesion and reliability of the passivation layer for various applications. The incorporation of silicon dioxide film had successfully provided reliable passivation protection especially for microfluidic devices application. In order to avoid flow turbulence caused by wire bonding wires, the wire bonding wires are omitted by deploying through-substrate conductive vias whereas connected to the carrier printed circuit board of sensor chip. The present invention disclosed a novel micromachining process and designed structure to form hermit sealing between the sensor chip and the carrier printed circuit board. The hermit sealing underneath the sensor chip can protect the bonding connections from exposing to liquid flow media and avoid short circuitry or induce undesired chemical corrosion. More particularly, the embodiments of the current invention relates to formation steps …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.