JPS60110160A - Static induction type thyristor - Google Patents

Abstract

PURPOSE:To increase the voltage gain and to readily control a current by partly forming a high impurity concentration region in a low impurity concentration region from the first electrode. CONSTITUTION:An anode electrode 1, a P type high impurity concentration region 2, an N type impurity or N type low impurity concentration region 3, an N type high impurity concentration region 4, a cathode electrode 5 and a gate electrode 9 are provided. A P type high impurity concentration region 6 is buried dispersively in the N type impurity or N type low impurity concentration region 3, and a P type high impurity concentration region 8 of a current control electrode is formed in the region 3 from the electrode 5. Thus, the pinch-off of a depletion layer is facilitated between gates, the abrupt implantation or stop of carrier can be performed by the high or low potential barrier, the voltage stopping gain is improved, and the current can bae turned ON or OFF in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic induction thyristor, and particularly to its gate (electrode for controlling carriers and impurity density region) structure.

Conventional statically induced thyristor, i.e. embedded (G) 8I
As shown in FIG. 1, the thyristor has a structure in which a p-type high impurity density region 6 is embedded in an n-type impurity or n-type low impurity density region 3 in a dispersed manner. A P-type high impurity density region 2 is formed on the entire surface of the electrode 3, and an anode electrode 1 is further provided. An n-type high impurity density region 4 is formed on the main surface of the plate, and a cathode electrode 5 is further provided. Further, the P-type highly impurity-concentrated region 6 is connected to a buried gate terminal 7.

In such a structure, there is a problem that when the channel width is narrowed in order to increase the voltage blocking gain, the rated current becomes small. Furthermore, when the channel width is increased, the voltage gain (a) decreases, and a large current cannot be turned off (transition from a conducting state to a blocking state).

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrostatic induction thyristor which can improve these drawbacks, increase voltage gain, and thereby facilitate current control.

In the present invention, a high impurity density region of one conductivity type and a low impurity density region of one conductivity type are sequentially connected under a first electrode, and regions of opposite conductivity type are embedded in a dispersed manner in the low impurity density region. The electrostatic induction thyristor is characterized in that a high impurity density region of an opposite conductivity type is partially formed in the low impurity density region from the first electrode.

Next, the present invention will be described in detail with reference to the drawings.

FIG. 2 is a sectional view showing an electrostatic induction thyristor according to an embodiment of the present invention.

In the figure, the electrostatic induction thyristor has an anode electrode 1
, P-type cavity impurity density region 2. n-type impurity or n-type low impurity density region 3, n-type high impurity density region 4. It has a cathode electrode 5 and a gate electrode 9, and this n-type impurity or n
P-type cavity impurity density regions 6 are embedded in a dispersed manner in the type low impurity density region 3.

From the cathode electrode 5, a P-high impurity density region 8, which is a flow control electrode, is formed in the n-type impurity or nff1 low impurity density region 3. For example, the impurity density of the P-type cavity impurity density regions 2 and 6.8 and the n-type high impurity density region 4 is 1×2020 crrL−1, the impurity density of the n-type low impurity density region 3 is lXlO121, and the gate interval is 10~ It is assumed to be 20 μn1.

Such a structure facilitates the pinch-off of the depletion layer between the grooves and the rapid carrier injection, due to the lower potential barrier! cIT function. This improves the impedance blocking gain, allowing the current to be turned on and off in a short time, and since the gate III is wide, the pinch-on distance of the depletion layer is long.

High voltage resistance is possible.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional thyristor of the 1-disturbance type (embedded type);
FIG. 2 is a cross-sectional view of an inductive thyristor. In the figure, 1... Anode electrode, 2... P-type impurity dense region, 3... N-type impurity or nii impurity density region. 4...N-type high impurity density region, 5...
Yin 穐'g憔, 6...P-type high impurity density region, 7
. . . Buried gate terminal, 8 . . . P high impurity density region, 9 . . . Gate potential. 1st concave 2nd figure

Claims (1)

[Claims] A static induction thyristor in which a high impurity density region of one conductivity type and a low impurity density region of one conductivity type are sequentially connected under a first electrode, and medium voltage opposite conductivity type regions are embedded in a dispersed manner in the low impurity density region. 2. The electrostatic induction thyristor according to claim 1, wherein a high impurity density region of an opposite conductivity type is partially formed in the low impurity density region from the first electrode.