JPH0366184A - Semiconductor magnetic sensor - Google Patents

Abstract

PURPOSE:To enhance the sensitivity of a semiconductor Hall IC by using an insulation gate type compound semiconductor Hall element. CONSTITUTION:A MOS type FET section forms a P-type channel region 2 on an insulation substrate 1. An N-type source and drain regions 3 and 4 are formed with the region 2 sandwiched therebetween, and source and drain electrode 5 and 6 are provided. An Si monocrystalline thin film is inserted on the P-type channel region 2 to reduce the interface level between a compound semiconductor and an insulation film, thereby forming a gate oxidation film 8. Furthermore, a gate electrode 9 is installed. A field effect transistor is used on a magnetic field detection section so that a very large space may be obtained due to its thin channel.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor magnetic sensor (semiconductor Hall IC) with a built-in integrated circuit that uses a compound semiconductor such as GaAs insulated gate field effect transistor as a magnetic sensing portion.

[Summary of the invention]

The present invention uses a compound semiconductor insulated gate field effect transistor in a magnetic sensing section to increase the sensitivity of a semiconductor Hall IC.

[Conventional technology]

As semiconductor Hall ICs, St MOS type and bipolar type have been put into practical use. Also, in the field of compound semiconductors, an MES type using bulk GaAs has been put into practical use.

[Problem to be solved by the invention]

Among the Hall ICs described above, St Hall ICs have lower mobility than compound semiconductors, and therefore are inferior in sensitivity. In addition, GaAsM E S-type Hall ICs have excellent temperature characteristics, output sensitivity characteristics, and high-temperature operation;
Since the Hall element portion is formed by ion implantation, the active layer is approximately 1,711,111 layers, which has the disadvantage of low sensitivity.

[Means to solve the problem]

In order to solve the above problems, in the present invention, by using an insulated gate compound semiconductor Hall element,
The effective thickness of the active layer was set to several hundred layers.

[Effect]

With the above configuration, a Hall IC with higher sensitivity can be manufactured.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

Here, the compound semiconductor is GaAs, and the insulated gate structure will be described only for a MOS type.

FIG. 1 shows an example of the cross-sectional structure of an MO3 type Hall IC according to the present invention. The MO3 type FET section is made of a semi-insulating GaAs substrate 1
A P-type channel region 2 is formed, and a GaA
N-type source and drain regions 3, 4 are provided by s, and source and drain electrodes 5.6 are provided. An St single crystal thin film 7 is inserted on the P-type channel region 2 to reduce the interface level between the compound semiconductor and the insulating film, a gate oxide film 8 is formed, and a gate electrode 9 is further provided. . MO3 type Hall element part is also MO3 type FET
It is similar to , but the following points are different. In the MO3 type Hall element part, the gate electrode 9 and drain electrode 6 of the MO3 type transistor are integrated, and an n type inversion layer is always formed in the P type channel region, and from the source region 3 to the drain region 4. Electrons are always moving. It also has a pair of Hall terminals 10 for detecting Hall voltage when a magnetic field is applied within the channel.

〔Effect of the invention〕

Since the present invention uses a brushed edge gate type field effect transistor in the magnetic field sensing section, the product sensitivity KNKH showing the Hall element sensitivity expressed by the following formula = f) IRII/
d (where fx is a factor related to the shape of the element, RH is the Hall coefficient, and d is the thickness) can be very large for channels as thin as several hundred.

In the example, only an example in which a semi-insulating GaAs substrate was used and a P-type channel region was formed was explained.
An s-substrate may also be used.

[Brief explanation of drawings]

FIG. 1 is a structural sectional view of an MO3 type Hall IC according to the present invention. 1...Semi-insulating GaAs 2...P-type channel region 3...4...5...6...7...8...9...IO...N-type source region/n-type drain region・Source electrode ・Drain electrode ・St single crystal thin film ・Gate oxide film ・Gate electrode ・Hall terminal or more

Claims (1)

[Claims] A semiconductor magnetic sensor in a Hall IC, characterized in that a magnetic sensing section is composed of a compound semiconductor insulated gate field effect transistor.