JPH10274583A - Semiconductor pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor pressure sensor low in cost and strong against vibration. SOLUTION: A semiconductor pressure sensor chip 1 is jointed to a glass base seat 2, and an electrode of the semiconductor pressure sensor chip 1 is electrically connected to a circuit pattern 4, formed on a base substrate 3, through a bump 5 and die-bonded to the base substrate 3 by an adhesive 6. At this time, the outer peripheral surface of the semiconductor pressure sensor chip 1 is covered with the adhesive 6 so as not to be in contact with a sealing resin 8. An atmosphere open hole 3a communicated with a diaphragm 1a is formed in the base substrate 3, and a taper 3b is formed on the semiconductor pressure sensor chip mounted face side of the atmosphere open hole 3a. One end of a pressure lead-in member 7 is inserted in a through hole 2a of the glass base seat 2, and the pressure lead-in member 7, glass base seat 2 and semiconductor pressure sensor chip 1 are sealed with the sealing resin 8 excluding the side, different from the side inserted in the glass base seat 2, of the pressure lead-in member 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor pressure sensor.

[0002]

2. Description of the Related Art FIG. 2 is a schematic sectional view showing a state in which a semiconductor pressure sensor according to a conventional example is mounted on a motherboard 3. As shown in FIG. In the figure, in the semiconductor pressure sensor, a semiconductor pressure sensor chip 1 is bonded to a glass pedestal 2 by an anodic bonding method or the like, and a concave portion 9a is provided substantially at the center of the bottom surface of the resin-molded package body 9, and the glass pedestal 2 is placed there. It is mounted with an adhesive 6 or the like. In the upper part of the package body 9, a pressure introducing hole 9b is formed which communicates with the semiconductor pressure sensor chip 1 through a through hole 2a formed substantially at the center of the glass pedestal 2.

The opening of the concave portion 9a formed on the bottom surface of the package body 9 is closed by a lid 10, so that the inside of the concave portion 9a becomes a pressure reference chamber 11 with improved sealing.

The semiconductor pressure sensor chip 1 has a single crystal silicon substrate having a pressure receiving surface formed on one surface, a diaphragm 1a for converting pressure into stress, a strain gauge (not shown), and electrodes (not shown). In this method, a change in pressure is converted into a change in electric resistance by the piezoresistance effect and output.

The electrodes formed on the semiconductor pressure sensor chip 1 and the leads 12 integrally formed on the package body 8 are connected by bonding wires 13 such as Au wires, and the leads 12 are mounted with the semiconductor pressure sensors. In order to connect with a circuit pattern (not shown) formed on the motherboard 3, after the diver of the lead frame serving as the lead 12 is cut, the tip portion of the portion protruding from the side surface of the package body 9 is substantially vertically downward. It is bent. The tip of the lead 12 is connected to the socket 1 mounted on the mother board 3.
Inserted into 4. Thus, the semiconductor pressure sensor is mounted on the motherboard 3.

Next, a different example of the conventional semiconductor pressure sensor will be described with reference to FIG. FIG. 3 is a schematic cross-sectional view showing a state in which a semiconductor pressure sensor according to a conventional example is mounted on a mother board 3. For convenience of description, the same components as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof is omitted. The example shown in FIG. 3 differs from the example shown in FIG. 2 in the shape of the leads and the mounting method. In the example shown in FIG. 3, the leads 15 protruding from the side of the package body 9 are provided.
Is bent diagonally downward, and further, its tip is
It is bent so as to be substantially horizontal in the direction opposite to the package body 9 side. The circuit pattern 4 is formed on the mother board 3 corresponding to the shape of the lead 15, and is joined to the tip of the lead 15 by solder 16.

[0007]

However, in the above configuration, the semiconductor pressure sensor chip 1 is mounted on the package body 9 once, and then the pressure sensor is mounted on the mother board 3 on which the circuit pattern 4 is formed. , The assembly man-hours increased and the cost was increased.

Further, since the electrical connection between the electrodes of the semiconductor pressure sensor chip 1 and the leads 12 and 15 is made by the bonding wires 13, there is a problem that the bonding strength is weak and the vibration is weak.

[0009] The present invention has been made in view of the above points, and its object is to provide a low-cost,
An object of the present invention is to provide a semiconductor pressure sensor that is resistant to vibration.

[0010]

According to the first aspect of the present invention,
A semiconductor pressure sensor chip having a thin diaphragm and electrodes, a glass pedestal having a through hole joined to the semiconductor pressure sensor chip, and a pressure introducing hole inserted into the through hole. And a mother board having an atmosphere opening hole and a circuit pattern on which the semiconductor pressure sensor is mounted, and the circuit pattern is electrically connected to the electrode via a bump. Connected, the semiconductor pressure sensor chip is arranged on the mother substrate so that the atmosphere opening hole communicates with the diaphragm,
One surface of the diaphragm is set to atmospheric pressure by the atmosphere opening hole, and the pressure applied from the pressure introduction hole to the other surface is applied to the diaphragm through the through hole. It is assumed that.

According to a second aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, a taper is formed on a side of the mother substrate where the semiconductor pressure sensor chip is mounted in an atmosphere opening hole of the mother substrate. Things.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view showing a semiconductor pressure sensor according to one embodiment of the present invention. In addition,
For convenience of explanation, the same components as those in FIGS. 2 and 3 are denoted by the same reference numerals, and description thereof is omitted. Semiconductor pressure sensor chip 1
Is bonded to the glass pedestal 2 by an anodic bonding method or the like, and the electrodes of the semiconductor pressure sensor chip 1 are electrically connected to the circuit patterns 4 formed on the mother substrate 3 via the bumps 5 and the rubber and gel The mother substrate 3 is die-bonded with a low-stress adhesive 6 such as a silicone resin or an epoxy resin. At this time, the outer peripheral surface of the semiconductor pressure sensor chip 1 is covered with the adhesive 6 so that a sealing resin 8 described later does not come into contact with the semiconductor pressure sensor chip 1. The mother board 3 has
An air opening hole 3a communicating with the diaphragm 1a is formed, and a taper 3b is formed on the semiconductor pressure sensor chip 1 mounting surface side of the air opening hole 3a.

One end of a resin-molded pressure-introducing member 7 having a pressure-introducing hole 7a substantially at the center is inserted into the through-hole 2a of the glass pedestal 2. It is bonded to the glass pedestal 2 by the adhesive 6. The pressure applied from the pressure introducing hole 7a is configured to communicate with the diaphragm 1a through the through hole 2a.

The pressure introducing member 7, the glass pedestal 2, and the semiconductor pressure sensor chip 1 are sealed with a sealing resin 8 except for the side of the pressure introducing member 7 different from the side inserted into the glass pedestal 2. .

Therefore, in the present embodiment, the step of mounting the semiconductor pressure sensor chip 1 on the package body as in the prior art can be omitted, and the number of steps can be reduced, and the cost can be reduced.

Since the electrodes of the semiconductor pressure sensor chip 1 are electrically connected to the circuit pattern 4 by the bumps 5, the reliability against vibration is improved.

In this embodiment, since the taper 3b is formed on the mounting side of the glass pedestal 2 in the air opening hole 3a of the motherboard 3, the air opening hole 3a is closed by the adhesive 6. Can be prevented.

In this embodiment, the glass pedestal 2 is joined to the semiconductor pressure sensor chip 1.
There is no need to be limited to this, and only the semiconductor pressure sensor chip 1 is die-bonded on the motherboard 3,
The pressure introducing member 7 may be directly bonded to the semiconductor pressure sensor chip 1 with the adhesive 6, so that the semiconductor pressure sensor can be reduced in thickness.

Further, in this embodiment, one side of the diaphragm 1a is set to the atmospheric pressure by the air opening hole 3a. However, the present invention is not limited to this. Is also good.

[0020]

According to the first aspect of the present invention, there is provided a semiconductor pressure sensor chip having a thin diaphragm and electrodes, a glass pedestal having a through hole joined to the semiconductor pressure sensor chip, and a through hole. A pressure introducing member having a pressure introducing hole inserted into the hole, and a mother substrate having an atmosphere opening hole and a circuit pattern for mounting a semiconductor pressure sensor, wherein the circuit pattern has a bump. The semiconductor pressure sensor chip is disposed on the motherboard so that the air opening hole communicates with the diaphragm, and one surface of the diaphragm is brought to the atmospheric pressure by the air opening hole. Since the pressure applied from the pressure introducing hole to the other surface is applied to the diaphragm through the through hole, the process of mounting the semiconductor pressure sensor chip on the package body as in the related art is performed. It can be omitted, the number of steps can be reduced and the cost can be reduced. Since the electrodes of the semiconductor pressure sensor chip are electrically connected to the circuit pattern by bumps, the reliability against vibration is improved, It was possible to provide a semiconductor pressure sensor that was cost-effective and resistant to vibration.

According to a second aspect of the present invention, in the semiconductor pressure sensor according to the first aspect, a taper is formed on the side of the mother substrate where the semiconductor pressure sensor chip is mounted in the open-to-atmosphere hole. When the pressure sensor chip is mounted on the motherboard, it is possible to prevent the air opening hole from being closed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a semiconductor pressure sensor according to one embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a state where a semiconductor pressure sensor according to a conventional example is mounted on a mother board.

FIG. 3 is a schematic cross-sectional view showing a state in which a semiconductor pressure sensor according to a conventional example is mounted on a mother board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor pressure sensor chip 1a Diaphragm 2 Glass pedestal 2a Through hole 3 Mother substrate 3a Open air hole 3b Taper 4 Circuit pattern 5 Bump 6 Adhesive 7 Pressure introducing member 7a Pressure introducing hole 8 Sealing resin 9 Package body 9a Depression 9b Pressure introduction Hole 10 Lid 11 Pressure reference chamber 12 Lead 13 Bonding wire 14 Socket 15 Lead 16 Solder

Claims (2)

[Claims] 1. A semiconductor pressure sensor chip having a thin diaphragm and electrodes, a glass pedestal having a through hole joined to the semiconductor pressure sensor chip, and a pressure inserted into the through hole. A pressure introducing member having an introduction hole, and a mother substrate having an atmosphere opening hole and a circuit pattern for mounting the semiconductor pressure sensor, wherein the circuit pattern is formed via bumps. The semiconductor pressure sensor chip is disposed on the motherboard so as to be electrically connected to an electrode and communicate with the diaphragm so that the atmosphere opening hole communicates with the diaphragm. Wherein the pressure applied from the pressure introduction hole to the other surface is applied to the diaphragm through the through hole. 2. The semiconductor pressure sensor according to claim 1, wherein a taper is formed on a side of the mother substrate on which the semiconductor pressure sensor chip is mounted in an atmosphere opening hole.