JPS63151090A - Hall effect semiconductor device - Google Patents

Abstract

PURPOSE:To improve surge resistance and to protect a Hall element against a surge damage by containing a protection diode in a package. CONSTITUTION:A cross n-type Hall element region 10 is formed on a substrate 9, and high concentration n-type contact regions 11-14 are respectively formed at 4 cross ends. P-type anode regions 15, 151 are superposed on the regions 12, 14, and n-type cathode regions 16, 161 are respectively superposed on the regions 15, 151. Further, wiring layers 17, 18 are formed between the regions 11, 13 and cathode regions 16, 161. Electrodes 19 are formed on the contact regions, and the electrodes are connected by fine metal wirings to the leads. Thus, a protection diode of bidirectional structure is formed between the input and output electrodes on the same substrate as the Hall element.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a Hall effect semiconductor device in which a package includes a diode (hereinafter referred to as a protection diode) that protects a Hall element from surges.

2. Description of the Related Art In recent years, Hall effect semiconductor devices using InSb and GaAs as starting materials have been widely used in VTR capstan motors and CD D
Applications are rapidly expanding to consumer equipment, mainly D motors, automotive motors, various position sensors, computer fan motors, and other industrial equipment.

A conventional Hall effect semiconductor device will be described below with reference to the schematic diagram of FIG. 6.

In FIG. 6, 1 is an input electrode terminal on the positive side, 2 is an input electrode terminal on the negative side, 3 is an output electrode terminal on the positive side, 4 is an output electrode terminal on the negative side, and 5 is formed on the semiconductor substrate. It is a sensitive part of a Hall element, and 6 indicates a mold package.

The operation of the Hall effect semiconductor device configured as described above will be described below.

Generally, in the constant voltage operation method, a constant voltage is applied between input electrode terminals, and a current is caused to flow according to the internal resistance of the Hall element. When a magnetic field is applied to the sensing section 5 from the outside, a potential difference is generated between the output electrode terminals due to the Hall effect. This effect can be applied and used as a magnetic sensor.

Problems to be Solved by the Invention In recent years, in order to miniaturize Hall effect semiconductor devices, the size of the Hall element has become smaller, and the distance between electrodes has become shorter, making them less susceptible to surges.

By the way, when using Hall effect semiconductor devices as various devices, reliability is becoming increasingly important.

However, in the conventional configuration, if a surge or noise is applied between each terminal from the outside, there is no protection circuit, and the semiconductor forming the Hall element or the contact area between the semiconductor and the electrode may be destroyed, resulting in a defect. was there.

The present invention solves the above problems, and is a surge-resistant Hall effect semiconductor device that absorbs surges and noises even if they are applied to the electrode terminals, and does not cause any change in the sensitive part of the Hall element or the electrodes. The purpose is to provide the following.

Means for Solving the Problems In order to achieve this object, the Hall effect semiconductor device of the present invention provides a Hall effect semiconductor device formed on a semiconductor substrate, a hole between a pair of input electrodes of the Hall element, between a pair of output electrodes, and There are only two diodes bidirectionally connected in series between the input and output electrodes, and the diodes and the Hall element are housed in a package.

According to this structure, even if a surge is applied to the electrode terminal, the surge current does not flow to the Hall element but to the diode.

Embodiment An embodiment of the Hall effect semiconductor device of the present invention will be described with reference to the schematic configuration diagram of FIG.

In FIG. 1, 1 is an input electrode terminal on the positive side, 2 is an input electrode terminal on the negative side, 3 is an output electrode terminal on the positive side, 4 is an output electrode terminal on the negative side, and 5 is a Hall element formed of a semiconductor. 7 is a bidirectional protection diode inserted between the input electrodes and connected in series with two diodes with opposite polarities; 8 is a bidirectional protection diode inserted between the output electrodes; 6 shows a mold package in which these are sealed.

The operation of the Hall effect semiconductor device configured as described above will be described below.

Design the withstand voltage of the bidirectional protection diode to be at least the maximum rated value guaranteed between the electrodes where this diode is inserted, but not too high. By doing this, the maximum rated voltage will be maintained during operation. Since it is used below the value,
The Hall element is not affected by protection diodes during operation. If a surge or noise is applied between the human electrodes or the output electrodes on the connected circuit or due to an accident, the surge voltage is a high voltage, so among the bidirectional protection diodes, the reverse diode will break down against the surge voltage. This causes a surge current to flow through the protection diode. As a result, the Hall effect semiconductor device can be protected without causing disturbance of the crystal in the sensitive part of the Hall element or abnormalities in the contact part between the electrode and the semiconductor forming the Hall element.

Next, a concrete example of the structure of the protection diode is shown in FIG.

Figure 2 shows a structure in which the protection diode is formed on the same substrate as the Hall element. Figure 2 (a) is a plan view, and Figure 2 (b) is the A-A line in (a). FIG.

As shown in the figure, a cross-shaped n-type Hall element region 10 is formed on a semi-insulating GaAs substrate 9, and highly doped n-type contact regions 11. 12, 13 and 14 are formed. The contact regions 12 and 14 also serve as cathode regions of the diodes. P-type anode regions 15 and 151 are formed on these contact regions 12 and 14 with their ends slightly overlapping, and n-type cathode regions 16 and 161 are formed on these anode regions 15 and 151, respectively, with their ends slightly overlapped. has been done. Further, a wiring layer 17 is formed between the contact region 11 and the cathode region 16, and a wiring layer 18 is formed between the contact region 13 and the cathode region 161. Also,
Electrodes 19 are formed on each of the contact regions 11, 12, 13 and 14, and although not shown, these electrodes and leads are connected by metal fs wires. This results in a structure in which a protection diode with a bidirectional structure is formed between the input and output electrodes on the same substrate as the Hall element.

Another example of the protection diode is a hybrid structure in which the protection diode is separately formed on a substrate different from the substrate on which the Hall element is formed, and the protection diode is incorporated into a package.

When a protection diode is provided between the input electrodes in Figure 3,
A comparison of surge resistance when not provided is shown. From this figure,
By providing a protection diode, surge resistance is increased (
You can see that it is growing.

Next, FIGS. 4 and 5 show another embodiment in which protection diodes are connected between various electrodes. Note that 19 to 22 are bidirectional protection diodes. In this way, the protective diode may be connected between the electrode terminals where surges are likely to enter due to the relationship with the applied equipment.

Effects of the Invention According to the Hall effect semiconductor device of the present invention, by incorporating a protection diode into the package, surge resistance can be greatly improved, and the Hall element can be protected from surge damage.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of the Hall effect semiconductor device of the present invention, FIG. 2 is a plan view and a cross-sectional view of a protection diode formed on the same substrate as a Hall element, and FIG. A diagram comparing the surge resistance of Hall effect semiconductor devices,
4 and 5 are schematic configuration diagrams showing other embodiments, and FIG. 6 is a schematic configuration diagram of a conventional Hall effect semiconductor device. 1...Positive side input electrode terminal, 2...Negative side input electrode terminal, 3...Positive side output electrode terminal, 4...Negative side output electrode Terminal, 5...
Sensing part of Hall element, 6...Mold package, ? , 8, 19, 20.21.22... Protection diode, 9... Semi-insulating GaAs substrate, 1
0... Hall element area, 11.13...
- Contact region, 12.14... contact region and cathode region, 15,151... anode region, 16,161... cathode region,
17.18... Wiring layer, 19... Electrode. Name of agent: Patent attorney Toshio Nakao and one other person Figure 3, Figure 4, Figure 5, Figure 6

Claims (3)

[Claims] (1) A Hall element formed on a semiconductor substrate and two wires connected in series in both directions between a pair of input electrodes of the Hall element, between a pair of output electrodes, and between the input/output electrodes.
A Hall effect semiconductor device comprising a diode, the diode and the Hall element being housed in the same package. (2) The Hall effect semiconductor device according to claim 1, wherein the diode is formed on the same substrate as the substrate on which the Hall element is formed. (3) The Hall effect semiconductor device according to claim 1, wherein the diode is formed on a substrate different from the substrate on which the Hall element is formed.