CN202917496U

CN202917496U - Locomotive thyristor

Info

Publication number: CN202917496U
Application number: CN 201220591207
Authority: CN
Inventors: 杨成标; 吴拥军; 张桥; 刘小俐; 李娴; 张明辉; 任丽
Original assignee: HUBEI TECH SEMICONDUCTORS Co Ltd
Current assignee: HUBEI TECH SEMICONDUCTORS Co Ltd
Priority date: 2012-11-12
Filing date: 2012-11-12
Publication date: 2013-05-01
Anticipated expiration: 2022-11-12

Abstract

The title of the utility model is locomotive thyristor, belonging to the power semiconductor device technical field and mainly aiming to solve the problem that the stability and reliability of a present locomotive thyristor are influenced owing to on-state pressure drop and higher temperature rise. The locomotive thyristor is mainly characterized by comprising a tube or a plastic package shell, a semiconductor chip of a PNPN four-layer structure which is packaged in the tube or the plastic package shell and is formed by an anode doped region P, a long base region N, a cathode plane N type layer and a gate pole short base region P type area, an anode Molybdenum plate, a cathode surface metal coating and a chip table top protection glue layer; an anode doped region P surface of the PNPN four-layer structure semiconductor chip is a chemical roughness layer, an anode plane of the anode doped region P is provided with an anode P+ heavily doped region, the cathode plane N type layer is provided with a cathode doped region N and a semiconductor chip of a P+PNPN+ four-layer structure is formed. The locomotive thyristor possesses the characteristics of high frequency, long service life, high reliability, good consistency and low costs and is mainly used for a locomotive thyristor.

Description

The locomotive thyristor

Technical field

The utility model belongs to the power semiconductor technical field, relates to a kind of locomotive large power semiconductor device.

Background technology

Locomotive uses thyristor for the harsh requirement of client to high stability and the high reliability of device, on-state voltage drop and temperature rise when particularly reducing device output, we produce on the basis of thyristor the electronic technology in conjunction with modern high development in routine, adopt ripe thyristor production technology, produce plate silicon controlled technique in conjunction with our factory, through-flow large, pressure drop is low, temperature rise is low requirement be can reach, thereby the stability of device detection and the high reliability of operation improved.Behind the development requirement that this device is arranged, we produce the experience of controllable silicon series of products for many years in conjunction with company, indivedual key points in the production process are improved, simultaneously the operating personnel of original production line carried out suitable training, realized the trial-production production to this product, therefore, on personnel, technically all possessed the condition of produce promoting, analyze standard that indices meets the requirements of the customers and company dispatches from the factory from present sample test.

Thyristor generally comprises shell or plastic packaging housing, be encapsulated in semiconductor chip, anode molybdenum sheet, the cathode surface coat of metal and the chip table protection glue-line of the PNPN four-layer structure in this shell or the plastic packaging housing, wherein, owing to not adopting P ⁺PNPN ⁺Four-layer structure, thereby in the situation that through-flow large for locomotive, on-state voltage drop and temperature rise are higher, thereby affect stability and the reliability of thyristor.

Summary of the invention

The purpose of this utility model be exactly provide for above-mentioned weak point that a kind of high-frequency, long-life, reliability are high, high conformity and the low locomotive high-power thyristor of cost.

Technical solution of the present utility model is: a kind of locomotive thyristor; comprise shell or plastic packaging housing, be encapsulated in semiconductor chip, anode molybdenum sheet, the cathode surface coat of metal and the chip table protection glue-line of the PNPN four-layer structure that comprises in this shell or the plastic packaging housing that doped anode district P, growing base area N, cathode plane N-type floor, p type island region territory, the short base of gate pole consist of; it is characterized in that: the doped anode district P surface of described PNPN four-layer structure semiconductor chip is chemical roughness floor, and is provided with anode P at doped anode district P anode surface ⁺Heavily doped region, cathode plane N-type layer is provided with negative electrode heavily doped region N ⁺, form P ⁺PNPN ⁺The semiconductor chip of four-layer structure.

Doped anode district P described in the technical solution of the present utility model is surface concentration 2 ~ 8x10 ¹⁷Cm ^-3, junction depth 45 ~ 130 μ m the anode surface layer.

Negative electrode doped region N described in the technical solution of the present utility model is surface concentration 2 ~ 9x10 ²⁰Cm ^-3, junction depth 10 ~ 50 μ m high concentration N-type layer.

Growing base area N thickness described in the technical solution of the present utility model is 50-500 μ m.

Anode P+ heavily doped region doping content described in the technical solution of the present utility model is higher than negative electrode doped region N doping content, and anode P+ heavily doped region junction depth is significantly less than p type island region territory, the short base of gate pole junction depth.

The present invention is owing to adopting by shell or plastic packaging housing, being encapsulated in the semiconductor chip of the PNPN four-layer structure that comprises in this shell or the plastic packaging housing that doped anode district P, growing base area N, cathode plane N-type floor, p type island region territory, the short base of gate pole consist of, be chemical roughness floor with doped anode district P surface, and be provided with anode P at doped anode district P anode surface ⁺Heavily doped region, cathode plane N-type layer is provided with negative electrode heavily doped region N ⁺, form P ⁺PNPN ⁺The semiconductor chip of four-layer structure, thus have blocking voltage high, through-flow large, pressure drop is low, high-frequency, long-life, reliability are high, high conformity and the low characteristics of cost, can reach simultaneously 5000V and logical 5000A electric current, on-state voltage drop is less than 1.6V.The utility model can be widely used in the fields such as locomotive, national defence, environmental protection, and its social benefit is fairly obvious.

Description of drawings

Fig. 1 is the rectification circuit schematic diagram.

Fig. 2 is triode thyristor chip structure figure.

Fig. 3 is thyristor chip structure chart of the present utility model.

Fig. 4 is encapsulating structure figure of the present utility model.

Fig. 5 is the process chart that the utility model is produced.

Embodiment

Locomotive is usually used in the rectification circuit form with thyristor, and the rectification circuit schematic diagram as shown in Figure 1.

Extremely shown in Figure 5 such as Fig. 2, doped anode district P1, growing base area N2, short base P3, negative electrode doped region N4, gate pole 5, negative electrode 6, anode 7, anode P+ heavily doped region 8, Coating glue protect district 9.Corresponding identical among Fig. 1 Anodic doped region P1, growing base area N2, short base P3, negative electrode doped region N4, gate pole 5, negative electrode 6, anode 7 and anode P+ heavily doped region 8 and Fig. 2.

According to different application requirements, silicon single crystal is selected the NTD material, and resistivity is 230 ~ 430 Ω .cm, thickness 860 ~ 1300 μ m.Choosing of gross thickness both requires to guarantee that growing base area N2 realizes the withstand voltage requirement of device forward, is unlikely to again to increase pressure drop.

Doped anode district P1 and short base P 3 are carried out simultaneously the p type impurity diffusion first time and are obtained by two-sided, can be Al or Ga.Junction depth 45 ~ 160 μ m, surface concentration 2 ~ 8x10 ¹⁷Cm ^-3

After the surface protection of short base P 3 is good, by methods such as grinding, sandblast and chemical corrosions, antianode doped region P 1 carries out chemical roughness to be processed.Remove 3 ~ 150 μ m.

After antianode doped region P 1 carries out chemical roughness processing, doped anode district P 1 and short base P 3 surfaces are done oxidation processes, short base P 3 surface oxide layers are carried out selective etching, again the N-type Impurity Diffusion is done on short base P 3 surfaces, form negative electrode doped region N4.Junction depth 9 ~ 28 μ m, surface concentration 2 ~ 9x10 ²⁰Cm ^-3

Antianode doped region P 1 surface diffuses to form anode P+ heavily doped region 8 through too high surface concentration P type, junction depth 15 ~ 70 μ m.Diffusion is selected on anode P+ heavily doped region 8 surfaces in case of necessity.Coating glue protect district 9 is chip table protection glue-line, and is same as the prior art.The encapsulating structure of device is: KT110dT(as shown in Figure 4).

For reducing locomotive with leakage current and the recovery charge of thyristor, to spreading good silicon chip gold doping or mixing the platinum diffusion, to reduce minority carrier lifetime.Diffusion temperature is 830 ~ 880 ° of C, 20 ~ 45 minutes time.Also adopt electron irradiation, be characterized in that leakage current is little, hot properties is better, and the consistency of recovery charge and the softness factor is better, and therefore great majority adopt the electron irradiation mode.

With ready-made locomotive with thyristor silicon chip sintering on molybdenum sheet, again selective etch is carried out after the metal evaporation on short base P 3 and negative electrode doped region N4 surface, clear needed figure and gate pole 5, negative electrode 6 and the anode 7 isolated, molybdenum sheet is as the anode 7 of chip.At last chip is installed in the standard shell of customization, finishes the final packaging and testing that the utility model locomotive is used thyristor.

Technological process of the present utility model comprises wafer diffusion 10, chip manufacturing 11 and packaging and testing 12 as shown in Figure 5.The manufacturing process of this thyristor chip comprises that growing base area 2 is thinner, and anode tap p type island region territory 1 is higher and junction depth is more shallow, its design feature: P than cathode terminal p type island region territory 3 doping contents ⁺PNPN ⁺Execution mode is: form first the positive-negative-positive structure, then one of them P locality protection is being got up, at the concrete N of another P regional diffusion ⁺The zone forms a P in protected first P zone again ⁺The zone, adjustment and improvement by above-mentioned technique, device repetitive peak voltage is apparently higher than triode thyristor repetitive peak voltage, pressure drop is starkly lower than commonplace components, other characteristics also have clear improvement, specifically see Table one and table two (annotate: Electron irradiation technology should carry out according to Product Process parameter or customer demand, and indicating does not especially need electron irradiation).

Table one is the 100mm triode thyristor of same specification and locomotive with the main Static State Index test comparison of thyristor.

Figure 2012205912077100002DEST_PATH_IMAGE001

Data show, when identical forward off state voltage design, locomotive is with the average V of thyristor on-state voltage drop _TMThan the low 1.4V of conventional thyristor, reach 45%.

Table two is dynamic parameter sample testing contrasts.

Therefrom see: locomotive is faster than triode thyristor service time summary with thyristor, and recovery charge is less, and expansion voltage is lower, and the softness factor is larger.By Computer Simulation, its switching loss is little by 27%.

Above result of the test shows, locomotive on dynamic and static characteristic, has obvious advantage with the triode thyristor of thyristor with respect to conventional symmetric design.Its lower on-state loss that is in operation, so device reliability is higher.

Claims

1. locomotive thyristor; comprise shell or plastic packaging housing; be encapsulated in and comprise doped anode district P(1 in this shell or the plastic packaging housing); growing base area N(2); cathode plane N-type layer; the semiconductor chip of the PNPN four-layer structure that gate pole p type island region territory, short base (3) consists of; anode molybdenum sheet (5); the cathode surface coat of metal; and chip table protection glue-line; it is characterized in that: the doped anode district P(1 of described PNPN four-layer structure semiconductor chip) surface is chemical roughness floor; and at doped anode district P(1) anode surface is provided with anode P+ heavily doped region (8); cathode plane N-type layer is provided with negative electrode doped region N(4), form P ⁺PNPN ⁺The semiconductor chip of four-layer structure.

2. a kind of locomotive thyristor according to claim 1 is characterized in that: described doped anode district P(1) be surface concentration 2 ~ 8x10 ¹⁷Cm ^-3, junction depth 45 ~ 130 μ m the anode surface layer.

3. a kind of locomotive thyristor according to claim 1 and 2 is characterized in that: described negative electrode doped region N(4) be surface concentration 2 ~ 9x10 ²⁰Cm ^-3, junction depth 10 ~ 50 μ m high concentration N-type layer.

4. a kind of locomotive thyristor according to claim 1 and 2, it is characterized in that: described growing base area N(2) thickness is 50-500 μ m.

5. a kind of locomotive thyristor according to claim 1 and 2, it is characterized in that: described anode P+ heavily doped region (8) doping content is higher than negative electrode doped region N(4) doping content, anode P+ heavily doped region (8) junction depth is less than p type island region territory, the short base of gate pole junction depth.