JPH02218171A - Semiconductor pressure sensor - Google Patents

Abstract

PURPOSE:To enable the accurate temperature compensation to be performed even if a semiconductor pressure sensor chip and an IC chip with an amplifying circuit, etc., are not fixed on nearby positions by a method wherein a temperature compensating resistor to compensate the temperature characteristics of a span voltage is built in the semiconductor pressure sensor chip. CONSTITUTION:A temperature compensating resistor 4 to compensate the temperature characteristics of a span voltage of a semiconductor pressure sensor chip 1 is bulit in the said sensor chip 1 which is provided with a diaphragm part 3 wherein pressure sensing gauge resistors 2 are buired and the bridge circuit connected inside a silicon substrate is made. Within the semiconductor pressure sensor chip 1 provided with the span temperature compensating resistor 4, the temperature compensation can be performed even if the semiconductor chip 1 and an IC chip 5 with an amplifying circuit, etc., are not fixed on nearby positions.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to semiconductor pressure sensors.

[Prior Art] FIG. 3 is a cross-sectional view of a pressure sensor chip of a conventional semiconductor pressure sensor, and this semiconductor pressure sensor chip 10 has the following features:
It is made of silicon and has a diaphragm part 3 in which a gauge resistor 2 for sensing pressure is embedded. Four gauge resistors 2 are formed, and a bridge circuit is formed inside the substrate.

This semiconductor pressure sensor chip! . The sensor converts the sensed pressure into a corresponding voltage and applies it to the IC chip 5°, which includes an amplifier circuit 6 and the like, as shown in the circuit diagram of FIG. Conventionally, this IC chip 5° is provided with a span temperature compensation resistor 4° for compensating the temperature characteristics of the span voltage of the semiconductor pressure sensor chip 10.

[Problems to be Solved by the Invention] As described above, since the span temperature compensation resistor 4° is formed on the IC chip 5°, in order to accurately perform temperature compensation, it is necessary to connect the semiconductor pressure sensor chip 1° and the IC It is necessary to keep the temperature of the chip 5° as equal as possible, and for this reason, conventionally, semiconductor pressure sensor chips have been used. . There is also a restriction that the IC chip 5°, which includes the amplifier circuit 6 and the like for amplifying the output voltage of the semiconductor pressure sensor chip 1°, must be installed as close as possible.

The present invention has been made in view of the above-mentioned points, and provides a semiconductor pressure sensor in which temperature compensation can be performed without placing a semiconductor pressure sensor chip and an IC chip having an amplifier circuit etc. in close proximity. The purpose is to

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a semiconductor pressure sensor chip having a diaphragm portion embedded with a gauge resistor for sensing pressure. It has a built-in temperature compensation resistor to compensate for the temperature characteristics of the sensor.

[Function] According to the above configuration, since the temperature compensation resistor is built into the semiconductor pressure sensor chip, there is no need to mount the semiconductor pressure sensor chip and the IC chip having the amplifier circuit etc. close to each other as in the conventional example. This means that accurate temperature compensation can be performed even if they are installed separately.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a semiconductor pressure sensor chip 1 according to an embodiment of the present invention, and parts corresponding to the conventional example in FIG. 3 are given the same reference numerals.

This semiconductor pressure sensor chip l has four sensors that sense pressure.
Two gauge resistors 2 are formed by diffusion, and the back side is further etched to form a diaphragm portion 3. The four gauge resistors 2 are connected inside the silicon substrate to form a bridge circuit.

The above configuration is similar to the conventional example shown in FIG.

In the semiconductor pressure sensor chip l of this embodiment, the span temperature compensation resistor 4 for compensating the temperature characteristics of the span voltage is formed by diffusion in the same way as the gauge resistor 2. That is, this semiconductor pressure sensor chip (3) has a built-in resistor 4 for span temperature compensation, and a lead wire extraction portion (not shown) corresponding to this resistor 4 is also formed.

FIG. 2 is a circuit configuration diagram of the semiconductor pressure sensor chip I of FIG. 1 and an IC chip 5 having an amplifier circuit for amplifying the output voltage of this semiconductor pressure sensor chip
Portions corresponding to the conventional example in the figures are given the same reference numerals.

As shown in FIG. 2, the circuit configuration is similar to the conventional example shown in FIG. 4, but the semiconductor pressure sensor chip I has a built-in resistor 4 for span temperature compensation, so that
The C chip 5 is not provided with a span temperature compensation resistor 4.

Since the span temperature compensation resistor 4 is provided on the semiconductor pressure sensor chip l side in this way, the semiconductor pressure sensor chip 1 and the IC chip 5 having the amplifier circuit 6 etc. do not need to be mounted in close positions as in the conventional example. temperature compensation is also possible.

[Effects of the Invention] As described above, according to the present invention, the semiconductor pressure sensor chip has a built-in temperature compensation resistor for compensating the temperature characteristics of the span voltage of the semiconductor pressure sensor chip. Accurate temperature compensation can be performed without having to install the IC chip and the IC chip having an amplifier circuit and the like in close proximity as in the conventional example.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a semiconductor pressure sensor chip according to an embodiment of the present invention, FIG. 2 is a circuit diagram of the semiconductor pressure sensor chip of FIG. 1 and an IC chip, and FIG. 3 is a diagram of a conventional example. FIG. 4 is a sectional view showing the structure of a semiconductor pressure sensor chip, and is a circuit configuration diagram of a conventional semiconductor pressure sensor chip and an IC chip. t lo... Semiconductor pressure sensor chip, 2... Gauge resistance, 4.48... Resistance for span temperature compensation, 5.
5゜...IC chip.

Claims (1)

[Claims] (1) A semiconductor pressure sensor chip having a diaphragm portion embedded with a gauge resistor for sensing pressure has a built-in temperature compensation resistor for compensating for the temperature characteristics of the span voltage of the semiconductor pressure sensor chip. Semiconductor pressure sensor.