CN205159332U

CN205159332U - Horizontal slot insulated electrode bars bipolar transistor of shunt structural type

Info

Publication number: CN205159332U
Application number: CN201520767126.1U
Authority: CN
Inventors: 赵喜高
Original assignee: SHENZHEN KIA SEMICONDUCTOR TECHNOLOGY Co Ltd
Current assignee: SHENZHEN KIA SEMICONDUCTOR TECHNOLOGY Co Ltd
Priority date: 2015-09-30
Filing date: 2015-09-30
Publication date: 2016-04-13
Anticipated expiration: 2025-09-30

Abstract

The utility model discloses a horizontal slot insulated electrode bars bipolar transistor of shunt structural type, include the p type substrate by the formation of oxide film, the n - drift region that forms on the p type substrate, form two positive poles, a negative pole and a grid on the n - drift region, the p+ drift region and the n+ buffers that form between two positive poles the p+ shunt structure that forms between positive pole and the negative pole, constitute n+ cathodic region, p+ cathodic region and p - base region between negative pole and the grid. The utility model discloses a horizontal slot insulated electrode bars bipolar transistor of shunt structural type has increaseed breech lock current density, makes breakdown voltage exceed current general horizontal slot insulated -gate bipolar transistor's breakdown voltage to higher current density and forward voltage can be used, better effect is obtained.

Description

Diversion structure type lateral trench electrode insulation grid bipolar transistor

Technical field

The utility model relates to technical field of semiconductor device, is specifically related to a kind of diversion structure type lateral trench electrode insulation grid bipolar transistor.

Background technology

Fig. 1 is existing lateral trench insulated gate bipolar transistor structure chart, because electrode is groove structure, therefore can realize miniaturization, this also forms n+ negative electrode, p+ anode linkage and p+ shunt district, this is because groove-oxide-film plays the result of photomask effect effectively.And, because electric field on device concentrates on groove-oxidation film layer, can not only miniaturization be realized, even and if have p+ shunt, also there is higher blocking voltage.

Because this landscape insulation bar double-pole-type transistor is because of conductance modulation, its forward voltage drop is little, input impedance is large, therefore be a device being suitable for very much intelligence (smart) power IC, but there is because of its structure the parasitic thyristor be made up of p+ anode, n-drift layer, p-base, n+ negative electrode in landscape insulation bar double-pole-type transistor.

In addition, when landscape insulation bar double-pole-type transistor normally works, above-mentioned parasitic thyristor does not work, but when electric current reaches more than certain value, and parasitic thyristor will conducting, the characteristic of Here it is latch-up.If there is above-mentioned latch-up, landscape insulation bar double-pole-type transistor can lose the control ability of mos gate, and therefore latch-up is the current handling capability of restriction landscape insulation bar double-pole-type transistor, and one of key element determining safety operation area.In order to effectively improve so important latch-up, once there is the technology about groove structure type landscape insulation bar double-pole-type transistor.

But along with common lateral trench insulated gate bipolar transistor size reduces, the electrical characteristics comprising latch-up current density can be deteriorated, the problem therefore causing voltage collapse and latch-up to promote around the hole current by p-base has carried out repeatedly studying.The lateral trench electrode insulation grid bipolar transistor with p+ diversion structure then exists along with n-drift layer reduces, the structural defect that forward blocking voltage significantly reduces.

Utility model content

For the above-mentioned defect existed in prior art, the utility model discloses a kind of diversion structure type lateral trench electrode insulation grid bipolar transistor, increase latch-up current density, puncture voltage is made to exceed the puncture voltage of existing general lateral trench insulated gate bipolar transistor, and higher current density and forward voltage can be used, obtain better effect.

The technical solution of the utility model is as follows:

A kind of diversion structure type lateral trench electrode insulation grid bipolar transistor, comprises the p-type substrate formed by oxide-film; The n-drift region that described p-type substrate is formed; Described n-drift region forms two anodes, a negative electrode and grids; The p+ drift region formed between described two anodes and n+ buffering area, the p+ diversion structure formed between described anode and negative electrode; N+ cathodic region, p+ cathodic region and p-base is formed between described negative electrode and grid.

Disclosed in the utility model, diversion structure type lateral trench electrode insulation grid bipolar transistor has two current paths, wherein one as shown in above-mentioned prior art Fig. 1, identical with the path of existing lateral trench insulated gate bipolar transistor, in forward operating mode, anode pn bonding meeting conducting, and the n-drift region injected hole of past transistor; In addition, in hole, a part flows directly into p+ cathodic region from n-drift region without p-base.And another current path is, flow to p+ shunt district, electronic current induction hole current, makes its hole current without the p+ cathodic region of n+ cathode back, and through p+ shunt district, Contact cathod, and this electric current and latch-up are not theed least concerned; P+ diversion structure type lateral trench electrode insulation grid bipolar transistor structure, because hole current is through the p+ cathodic region at p+ shunt district and the back side, n+ cathodic region, and directly arrives negative electrode, therefore can improve anti-breech lock performance.

Accompanying drawing explanation

Fig. 1 is existing lateral trench insulated gate bipolar transistor structure chart;

Fig. 2 is the utility model structural representation in one embodiment;

Fig. 3 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of the utility model embodiment and the I-V performance diagram of existing lateral trench insulated gate bipolar transistor;

Fig. 4 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment of the present utility model and the Hall current flow graph of existing lateral trench insulated gate bipolar transistor;

Fig. 5 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment of the present utility model and the forward breakdown performance plot of existing lateral trench insulated gate bipolar transistor;

Fig. 6 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment of the present utility model and the turn-off characteristic figure of existing lateral trench insulated gate bipolar transistor.

Embodiment

Below in conjunction with accompanying drawing, embodiment of the present utility model is elaborated.

As shown in Figure 2, disclosed in the utility model, diversion structure type lateral trench electrode insulation grid bipolar transistor, comprises the p-type substrate 9 formed by oxide-film; The n-drift region 10 that described p-type substrate is formed; Described n-drift region forms two anodes, 1, negative electrode 2 and a grid 3; The p+ drift region 5 formed between described two anodes 1 and n+ buffering area 4, the p+ shunt district 6 formed between described anode 1 and negative electrode 2; N+ cathodic region 8, p+ cathodic region 7 and p-base is formed between described negative electrode 2 and grid 3, thus make diversion structure type lateral trench electrode insulation grid bipolar transistor have two current paths, wherein one identical with the path of the existing lateral trench insulated gate bipolar transistor shown in Fig. 1, in forward operating mode, anode pn bonding meeting conducting, and the n-drift region injected hole of past transistor; In addition, with regard to the effect of diversion structure type lateral trench electrode insulation grid bipolar transistor of the present utility model, in hole, a part flows directly into p+ cathodic region 7 from n-drift region 10 without p-base, and another current path is, flow to p+ shunt district 6, electronic current induction hole current, make its hole current without the p+ cathodic region of n+ cathode back, and through p+ shunt district, Contact cathod, and this electric current and latch-up are not theed least concerned.

Fig. 3 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment of the present utility model and current-voltage (I-V) performance plot of existing lateral trench insulated gate bipolar transistor, turn to the place in cathode resistor district to be exactly the place that latch-up occurs from anode resistance district, as shown in figure relatively, the latch-up current density of existing lateral trench insulated gate bipolar transistor and diversion structure type lateral trench electrode insulation grid bipolar transistor of the present utility model is respectively 540A/ and 1453A/, therefore, structure of the present utility model has than existing lateral trench insulated gate bipolar transistor, the superperformance of high 2.7 times of its latch-up current density, and p+ diversion structure type lateral trench electrode insulation grid bipolar transistor structure, because hole current is through the p+ cathodic region at p+ shunt district and the back side, n+ cathodic region, and directly arrive negative electrode, therefore anti-breech lock performance can be improved.

Fig. 4 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment and the Hall current flow graph of existing lateral trench insulated gate bipolar transistor, set forth the hole current vector of device in the on-state, can confirm from p+ anode toward n-drift region injected holes, part hole flows into p+ cathode layer from n-drift layer, and another part then flows into p+ shunt district from n-drift layer; In addition, there is not latch-up and collect the hole flowing into p+ negative electrode and p+ shunt district in negative electrode (2), therefore can find that a lot of hole concentrates on the n+ cathode layer back side and p+ shunt district; In contrast, at existing lateral trench insulated gate bipolar transistor, a lot of hole flows into negative electrode (2) through p-base layer, demonstrates the characteristic of above-mentioned Fig. 3.

Fig. 5 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment and the forward breakdown performance plot of existing lateral trench insulated gate bipolar transistor, there is one of characteristic of regulation device, namely forward stops characteristic, just generally speaking, if the length of n-drift layer reduces because of p+ shunt district, forward blocking voltage can significantly reduce; Given this, past originally cannot make the lateral trench insulated gate bipolar transistor with p+ shunt, but there is at the utility model the lateral trench insulated gate bipolar transistor of p-shunt, electrode have employed channel away, if therefore concentrate on groove-oxidation film layer at device inside electric field, punch-through breakdown phenomenon can more late appearance.Compared with onesize device, the forward blocking voltage of existing lateral trench insulated gate bipolar transistor is below 105V, the forward blocking voltage of the utility model structure is about 140V, therefrom known, the forward blocking voltage of p+ diversion structure type lateral trench electrode insulation grid bipolar transistor of the present utility model improves about 1.3 times than the forward blocking voltage of existing lateral trench insulated gate bipolar transistor.

Fig. 6 is the diversion structure type lateral trench electrode insulation grid bipolar transistor of preferred embodiment and the turn-off characteristic figure of existing lateral trench insulated gate bipolar transistor, with regard to electric insulation grid bipolar transistor, in a general case, the turn-off time is defined as the time reaching anode current initial value 10% in the on-state.The turn-off time of existing lateral trench insulated gate bipolar transistor is 2, and the pass of the present utility model end time is 0.3, and its switching speed known quickly.And the fast reason of switching speed is that groove-oxide-film occupies a part for n-drift region, makes the minority carrier being accumulated in n-drift layer have minimizing.

As mentioned above, effect of the present utility model is because diversion structure type lateral trench electrode insulation grid bipolar transistor is surrounded by groove-oxidation film layer, electric field moves on to groove-oxidation film layer, therefore the punch-through breakdown phenomenon of diversion structure type lateral trench insulated gate bipolar transistor can more late appearance, thus at lateral trench insulated gate bipolar transistor, p+ shunt does not affect punch-through.In addition, diversion structure type lateral trench electrode insulation grid bipolar transistor of the present utility model is than existing lateral trench insulated gate bipolar transistor, not only current density is higher, but also can use at forward voltage, therefore this is that a Best Practical of strategic industry of future generation and intelligent power IC industry is novel.

Above-described the utility model execution mode, does not form the restriction to the utility model protection range.Any do within spirit of the present utility model and principle amendment, equivalent to replace and improvement etc., all should be included within claims of the present utility model.

Claims

1. a diversion structure type lateral trench electrode insulation grid bipolar transistor, is characterized in that: comprise the p-type substrate formed by oxide-film; The n-drift region that described p-type substrate is formed; Described n-drift region forms two anodes, a negative electrode and grids; The p+ drift region formed between described two anodes and n+ buffering area, the p+ diversion structure formed between described anode and negative electrode; N+ cathodic region, p+ cathodic region and p-base is formed between described negative electrode and grid.

2. diversion structure type lateral trench electrode insulation grid bipolar transistor as claimed in claim 1, is characterized in that: described n-drift region epitaxial growth is formed at the front of described P type substrate.