# US 2017/0247250 A1 · Semiconductor pressure sensor for harsh media application

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2017/0247250 A1
- Document ID: US20170247250A1
- Status: Published application
- Kind: A1
- Application number: 15/445,096
- Filed: 2017-02-28
- Published: 2017-08-31
- Earliest claimed: 2016-02-29
- Assignees: Melexis Technologies SA
- Applicants: Melexis Technologies NV
- Inventors: Laurent OTTE; Jian CHEN; Appolonius Jacobus VAN DER WIEL
- Web page: https://patentgrep.com/patent/US20170247250A1

## CPC

- B81B 7/0058: {for protecting against damages due to external chemical or mechanical influences, e.g. shocks or vibrations}
- B81C 1/0023: {Packaging together an electronic processing unit die and a micromechanical structure die (MEMS packages B81B7/0032; MEMS packaging processes B81C1/00261)}
- G01L 9/0054: {integral with a semiconducting diaphragm}
- G01L 19/0645: {using isolation membranes, specially adapted for protection}
- G01L 19/147: {Details about the mounting of the sensor to support or covering means}
- G01L 23/24: {specially adapted} for measuring pressure in inlet or exhaust ducts of internal-combustion engines
- B81B 2201/0264: Pressure sensors
- B81B 2207/012: the micromechanical device and the control or processing electronics being separate parts in the same package
- B81B 2207/07: Interconnects
- B81B 2207/098: Arrangements not provided for in groups B81B2207/092 - B81B2207/097
- B81B 2207/115: Protective layers applied directly to the device before packaging
- B81C 2203/0792: Forming interconnections between the electronic processing unit and the micromechanical structure
- H10W 90/753: {between laterally-adjacent chips}
- B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00)
- B81C: PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS (making microcapsules or microballoons B01J13/02; processes or apparatus specially adapted for the manufacture or treatment of piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/01)
- G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G)
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10

## Abstract

A semiconductor pressure sensor assembly for measuring a pressure of an exhaust gas which contains corrosive components, comprising: a first cavity, a pressure sensor comprising first bondpads for electrical interconnection, a CMOS chip comprising second bondpads for electrical interconnection with the pressure sensor, an interconnection module having electrically conductive paths connected via bonding wires to the pressure sensor and to the CMOS chip; the interconnection module being a substrate with corrosion-resistant metal tracks, wherein the CMOS chip and part of the interconnection module are encapsulated by a plastic package.

## Claims

### Claim 1

A semiconductor pressure sensor assembly suitable for use under an exhaust gas environment of an automobile engine for measuring a pressure of the exhaust gas which contains corrosive components, the pressure sensor assembly comprising:
a first cavity comprising an opening for allowing exposure to said exhaust gas;
a pressure sensor arranged in said cavity, the pressure sensor comprising a plurality of first bondpads made of or covered by a first corrosion resistant material;
a CMOS chip mounted on a first substrate, the CMOS chip comprising a plurality bondpads without corrosion resistant material on top;
an interconnection module comprising a second substrate and a plurality of electrically conductive paths made of a second corrosion resistant material, each conductive path having a first bondpad and a second bondpad;
the first bondpads of the pressure sensor being connected via first bonding wires to the first bondpads of the interconnection module, the first bonding wires being made of a third corrosion resistant material;
the first bondpads of the CMOS chip being connected via second bonding wires to the second bondpads of the interconnection module;
wherein;
the CMOS chip and its first bondpads and the second bondpads of the interconnection module and the second bonding wires and part of the interconnection module are protected from exposure to said exhaust gas by encapsulation with a corrosion resistant plastic material.

### Claim 2 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, wherein the interconnection module is smaller than the sensor chip.

### Claim 3 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the first substrate is a lead frame, preferably a copper lead frame or a copper based lead frame.

### Claim 4 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the first corrosion resistant material is Au or Pt or an alloy consisting of a mixture of Au and Pt, or is an alloy containing at least Au or Pt;
and/or wherein the third corrosion resistant material is Au or Pt or an alloy consisting of a mixture of Au and Pt.

### Claim 5 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the second corrosion resistant material is a metal different from Aluminum and different from Copper,
or wherein the second corrosion resistant material is a metal alloy containing less than 5 atom % aluminum;
or wherein the second corrosion resistant material is a metal alloy containing less than 5 weight % aluminum;
or wherein the second corrosion resistant material is a metal alloy containing less than 5 atom % copper;
or wherein the second corrosion resistant material is a metal alloy containing less than 5 weight % copper.

### Claim 6 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the second corrosion resistant material is a single metal selected from the group consisting of Au, Pt, Pd, Ta, Ti, W, Ag, Mo; or
wherein the second corrosion resistant material is a metal alloy comprising at least one metal selected from the group consisting of Au, Pt, Pd, Ta, Ti, W, Ag, Mo; or
wherein the second corrosion resistant material is a metal alloy comprising at least two metals selected from the group consisting of Au, Pt, Pd, Ta, Ti, W, Ag, Mo; or
wherein the second corrosion resistant material is a Ni—Pd—Au stack.

### Claim 7 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the interconnection module is arranged next to the CMOS chip, and
wherein the pressure sensor is located at least partly above or on top of one or both of the CMOS chip and the interconnection module.

### Claim 8 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1,
wherein the interconnection module is mounted above or on top of the CMOS chip thereby defining a first portion of the CMOS chip which is overlaid by the interconnection module and a second portion of the CMOS chip which is not overlaid;
the second bondpads of the interconnection module and the second bonding wires and the second portion of the CMOS chip which is not overlaid by the interconnection module being encapsulated by the plastic package.

### Claim 9 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, further comprising a gel applied in the first cavity on top of the pressure sensor.

### Claim 10 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, wherein the substrate of the interconnection module is made of a material selected from the group consisting of glass, silicon, germanium, alumina, PCB material, a duroplast.

### Claim 11 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, wherein the CMOS chip is an integrated circuit comprising a microprocessor and non-volatile memory.

### Claim 12 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, wherein the CMOS chip further comprises second bondpads connected to the first substrate via third bonding wires, the third bonding wires also being encapsulated by the plastic package.

### Claim 13 (depends on 1)

A semiconductor pressure sensor assembly according to claim 1, having outer dimensions smaller than 5 mm×10 mm×8 mm, for example smaller than 2.4 mm×5.0 mm×4.0 mm, for example smaller than 2.0 mm×3.0 mm×3.0 mm, for example smaller than 1.5 mm×2.0 mm×2.0 mm.

### Claim 14 (depends on 1)

Method of manufacturing a pressure sensor assembly according to claim 1, comprising the steps of:
a) providing the first substrate;
b) providing the pressure sensor;
c) providing the interconnection module;
d) providing the CMOS chip;
e) mounting the CMOS chip on the first substrate, for example using soldering or using an adhesive;
f) mounting the interconnection module on the first substrate or on the CMOS chip, for example using an adhesive;
g) applying second bonding wires to interconnect the second pads of the interconnection module and the first pads of the CMOS chip;
h) optionally applying third bonding wires to interconnect second pads of the CMOS chip and the first substrate;
i) applying a plastic package to cover or encapsulate at least the CMOS chip, and the first pads of the CMOS chip, and the second bonding wires, and the second pads of the interconnection module by a corrosion-resistant plastic,
in such a way as to leave the first pads of the interconnection module exposed,
and in such a way as to form a cavity sufficiently large to accommodate the pressure sensor;
j) mounting the pressure sensor in the cavity to the first substrate or to the plastic package or to the interconnection module, for example using an adhesive;
k) applying first bonding wires to interconnect the first pads of the pressure sensor and the first pads of the interconnection module.

### Claim 15 (depends on 1)

Use of a semiconductor pressure sensor according to claim 1 for measuring a pressure of an exhaust gas of an automobile engine.