Flow sensor, method for manufacturing flow sensor and flow sensor module

Patent metadata

Field	Value
Publication number	US-11629988-B2
Application number	US-202017130247-A
Country	US
Kind code	B2
Filing date	Dec 22, 2020
Priority date	Dec 11, 2009
Publication date	Apr 18, 2023
Grant date	Apr 18, 2023

Abstract

A flow sensor includes a semiconductor, an electric control circuit, a lead frame, and a spacer. The spacer is disposed in a clearance between the lead frame and the semiconductor device on an opposite side from a joint portion of the semiconductor device with the lead frame on a side of the electric control circuit across the diaphragm disposed therebetween. A surface of the electric control circuit and a part of a surface of the semiconductor device is covered with resin while the air flow sensing unit is exposed. At the joint portion, the semiconductor device is attached to the lead frame via an adhesive.

First claim

What is claimed is:

1. A flow sensor comprising:
a semiconductor device having an air flow sensing unit and a diaphragm formed thereto;
an electric control circuit configured to control the semiconductor device;
a lead frame; and
a spacer, wherein
the spacer is disposed in a clearance between the lead frame and the semiconductor device on an opposite side from a joint portion of the semiconductor device with the lead frame on a side of the electric control circuit across the diaphragm disposed therebetween,
a surface of the electric control circuit and a part of a surface of the semiconductor device is covered with resin while the air flow sensing unit is exposed,
at the joint portion, the semiconductor device is attached to the lead frame via an adhesive, and
the spacer is formed of polytetrafluoroethylene, a fluorine resin, an epoxy resin, or a polycarbonate resin.

2. The flow sensor according to claim 1 , wherein a wire for transmitting electric signals from the semiconductor device and the lead frame is molded by the resin.

3. The flow sensor according to claim 1 , wherein the resin forms a continuous space with three sides of the semiconductor device, thereby surrounding the semiconductor device.

4. A method for manufacturing a flow sensor from a structure, comprising:
disposing an elastic film on a surface of an upper mold of the molds, wherein the structure includes
a semiconductor device having an air flow sensing unit and a diaphragm formed thereto,
an electric control circuit for controlling the semiconductor device,
a lead frame, and
a spacer, wherein
the spacer is disposed in a clearance between the lead frame and the semiconductor device on an opposite side from a joint portion of the semiconductor device with the lead frame on a side of the electric control circuit across the diaphragm disposed there between, and
at the joint portion, the semiconductor device is attached to the lead frame via an adhesive;

clamping a dam of the lead frame via the molds with varying a thickness of the elastic film for absorbing a dimension variation of the semiconductor device;
molding the structure; and
cutting away the dam excluding output terminals of the lead frame.

5. The method according to claim 4 , wherein the elastic film is formed by polytetrafluoroethylene, or a fluorine resin.

Assignees

• Hitachi Automotive Systems Ltd
• Hitachi Astemo Ltd

Inventors

• Kono Tsutomu
• Okamoto Yuuki
• Morino Takeshi
• Hanzawa Keiji

Classifications

• H10W90/754

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W72/5522

  comprising gold [Au] · CPC title

• H10W72/5449

  not being orthogonal to a side surface of the chip, e.g. fan-out arrangements · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title

• H10W70/40

  Leadframes · CPC title