JPH01201955A - Schottky diode - Google Patents

Abstract

PURPOSE:To reduce high-frequency serial resistance while improving pressure- tightness in the reverse direction by combining a conductive semiconductor doped with donors in high concentration and a semiinsulating semiconductor and forming an ohmic electrode on the side of a conductive semiconductor and a Schottky electrode on a semiinsulating semiconductor. CONSTITUTION:A semiinsulating Al GaAs layer 2 is formed between an n-type GaAs layer 1 and a Schottky electrode so that pressure-tightness in the reverse direction of the Schottky electrode 3 is increased. Accordingly, n-type GaAs can be made low-resisting by doping with a large amount of impurities so that high-frequency serial resistance is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a Schottky diode that can be used in a high frequency band.

Conventional pn junction diodes have poor high frequency characteristics due to the minority carrier accumulation effect, so Schottky diodes that utilize Schottky junctions of metals and semiconductors are used in high frequency bands (for example, Imai et al., compound semiconductor device Industrial Survey Wire Mesh 1984).

Hereinafter, the conventional Schottky diode as described above will be explained with reference to the drawings.

FIG. 2 is a structural diagram of a conventional Schottky diode.

In FIG. 2, 6 is an n-type semiconductor, 6 is a Schottky electrode, and 7 is an ohmic electrode.

The operation of the Schottky diode configured as described above will be described below.

In a Schottky diode, an electrical barrier unique to the material is created at the interface between the semiconductor and the metal (electrode). When an electric field is applied in a certain direction (forward direction) to the two electrodes of this diode,
A small stain flow flows through the barrier, and when an electric field is applied in the opposite direction (opposite direction), the barrier is too strong and the stain flow does not flow. Therefore, the diode exhibits rectifying characteristics.

Problems to be Solved by the Invention In order to improve the characteristics of the Shosso l-ki diode used in reverse bias, ■reducing the high frequency series resistance;
■It is important to increase the reverse breakdown voltage, but in conventional Schottky diodes, if the donor concentration of the semiconductor is high, the high frequency series resistance decreases, but the reverse breakdown voltage is small; if the concentration is low, the reverse breakdown voltage is 37, -5 Although the forward breakdown voltage is high, the high frequency series resistance is high, and the Schottky diode with low high frequency series resistance and high reverse breakdown voltage cannot be realized.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention provides a see-through diode capable of reducing high frequency series resistance and increasing reverse breakdown voltage.

Means for Solving the Problems In order to solve the above problems, the Schottky diode of the present invention has a conductive semiconductor heavily doped with a donor and a semi-insulating semiconductor, and an ohmic electrode and a semi-insulating semiconductor on the conductive semiconductor side. It has a structure in which a Schottky electrode is formed on an insulating semiconductor.

Since the working ohmic electrode side is a conductive semiconductor and the Schottky electrode side is a semi-insulating semiconductor, this configuration makes it possible to realize a Schottky diode with low high frequency series resistance and high reverse breakdown voltage.

Embodiment Hereinafter, one embodiment of the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows a structural diagram of a Schottky diode in a first embodiment of the present invention.

In FIG. 1, 1 is an n-type GaAs layer, 2 is a semi-insulating AgGaAs layer with a thickness of 500 mm, 3 is a Schottky electrode, and 4 is an ohmic electrode. Further, the surface area of the electrode at 3° is 5000 μm2.

The operation of the Schottky diode configured as described above will be described below.

Since the Schottky electrode is formed on a semi-insulating AgGaAs layer, its reverse breakdown voltage is high. Therefore, n-type GaAs can be doped with a large amount of impurities to make it low in resistance.
High frequency series resistance becomes smaller.

As described above, in this example, a diode with a breakdown voltage SOV and a high frequency series resistance of 02 Ω could be formed by forming 5008 semi-insulating AeGaAs layers between the n-type GaAs layer and the Schottky electrode.

Effects of the Invention As described above, the present invention realizes a Schottky diode with high breakdown voltage and low series resistance at high frequencies by forming a high-resistance A/GaAs layer between an n-type GaAs layer and a 5-layer electrode. It can be done, and its practical effects are great.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram of a Schottky diode according to an embodiment of the present invention, and FIG. 2 is a structural diagram of a conventional Schottky diode. 1...n-type semiconductor, 2-...high resistance semiconductor, 3-shot electrode, 4...ohmic electrode, 5...n
type semiconductor, 6. Schottky electrode, 7. Omic electrode. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
figure

Claims (1)

[Claims] A Schottky diode, characterized in that a semi-insulating semiconductor layer is provided on a conductive semiconductor layer, and a Schottky electrode is provided on the semi-insulating semiconductor layer.