CN105448846A - Low inductance thin and light type power module - Google Patents
Low inductance thin and light type power module Download PDFInfo
- Publication number
- CN105448846A CN105448846A CN201510976938.1A CN201510976938A CN105448846A CN 105448846 A CN105448846 A CN 105448846A CN 201510976938 A CN201510976938 A CN 201510976938A CN 105448846 A CN105448846 A CN 105448846A
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- shell
- terminal
- power terminal
- enclosure
- power model
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
- H01L24/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L24/10—Bump connectors ; Manufacturing methods related thereto
- H01L24/12—Structure, shape, material or disposition of the bump connectors prior to the connecting process
- H01L24/14—Structure, shape, material or disposition of the bump connectors prior to the connecting process of a plurality of bump connectors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/02—Containers; Seals
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
- H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
- H01L2224/10—Bump connectors; Manufacturing methods related thereto
- H01L2224/12—Structure, shape, material or disposition of the bump connectors prior to the connecting process
- H01L2224/14—Structure, shape, material or disposition of the bump connectors prior to the connecting process of a plurality of bump connectors
- H01L2224/141—Disposition
- H01L2224/1412—Layout
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- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Structures Or Materials For Encapsulating Or Coating Semiconductor Devices Or Solid State Devices (AREA)
Abstract
The invention relates to a low inductance thin and light type power module, comprising an enclosure, and a circuit which is composed of a semiconductor chip, power terminals and control terminals and is welded on a metal ceramic covered substrate; the power terminal is a cylinder with threads arranged in the inner hole; the bottom of the cylinder is fixed on the metal ceramic covered substrate; transversely and vertically intercrossed blocking strips are arranged on the shell wall of the enclosure; at least one limit post is arranged at the lower part of every blocking strip; the metal ceramic covered substrate is connected to the bottom of the enclosure; the limit posts on the blocking strips are abutted on the metal ceramic covered substrate; a soft silica gel layer is poured in the enclosure; the through holes arranged at periphery of the shell wall of the enclosure are used for releasing the stress generated when the silica gel layer expands and shrinks; every power terminal and every control terminal penetrate the silica gel layer; an epoxy resin and the enclosure, the blocking strips in the enclosure, every power terminal and every control terminal are cured to form an integrated structure. The invention has relatively low lead stray inductance and thermal resistance and can prevent the connection part of the terminals and the metal ceramic covered substrate from falling off.
Description
Technical field
The present invention relates to a kind of low inductance light and thin type power model, belong to power model manufacturing technology field.
Background technology
Power half guide module is used for inverter type welder, the controller of various Switching Power Supply and electric vehicle controller etc., and its Main Function the direct current of input is changed into three-phase alternating current to export.And power semiconductor modular, be that one or more driver element and one or more power model form three-phase circuit work.
Current power model mainly contains two kinds of structures, and a kind of height of power model of structure is at about 34mm, and the height of the power model of another kind of structure is at about 17mm.Height comprises copper coin in the module of 34mm, covers cermet substrate, semiconductor chip, device and power terminal, control terminal and shell, semiconductor chip, device power terminal and control terminal are welded on and cover on cermet substrate and form main circuit, power terminal passes the power terminal hole on the cover plate on shell, be stuck in after power terminal is bended on the nut seat of shell, this power terminal one end is weldingly fixed on to be covered on cermet substrate, the other end is then in vacant state, in vibration environment, the stiff end of power terminal is easily caused to come off.Some power terminals can adopt multiple bending structure for this reason, absorb and alleviate the impulsive force shaking and cause, and to alleviate the risk that power terminal comes off, but this structure turn increases the stray inductance that power touches block simultaneously.And height is comprised to copper coin at the power model of 17mm, covers cermet substrate, semiconductor chip, device and shell, semiconductor chip is welded on and covers on cermet substrate, is connected to form main circuit by aluminium wire and the power terminal be injection-moulded in shell.The power model of this structure, because the power terminal current capacity be injection-moulded in shell is little, therefore the big current that a lot of power terminal reaches certain is needed in shell, cause shell cost higher, in addition power terminal has a L-type bending at least, so make connection power terminal also have larger radian with the aluminium wire covering cermet substrate, therefore this power terminal bending structure and aluminium wire radian both increase the stray inductance of power model.Above-mentioned two kinds of structure power models all will cover cermet substrate and be welded on copper coin, and copper coin with cover cermet substrate by soldering-tin layer and be connected, copper coin has certain thermal resistance together with soldering-tin layer.
Summary of the invention
The object of this invention is to provide one and there is lower wiring parasitic inductance and thermal resistance, terminal can be stopped and cover cermet substrate junction and to come off the low inductance light and thin type power model occurred.
The present invention is the technical scheme achieved the above object: a kind of low inductance light and thin type power model, comprise shell and be welded on the semiconductor chip covered on cermet substrate, multiple power terminal and multiple control terminal form circuit, it is characterized in that: described power terminal is that endoporus establishes threaded cylinder, cylindrical bottom is fixed on to be covered on cermet substrate, horizontal and vertical crossing blend stop is provided with in the shell wall of described shell, blend stop bottom is provided with at least one limited post, cover cermet substrate and be connected to outer casing bottom, and the limited post on blend stop withstands on and covers on cermet substrate, soft silicon gel layer is marked with in shell, shell is provided with and air and the through hole that communicates in shell wall surrounding, described through hole is used for the Stress Release that produces when silicon gel layer expands and shrinks, each power terminal and each control terminal are through silicon gel layer, epoxy resin layer and shell, blend stop in shell and each power terminal and each control terminal are solidified into overall structure.
Wherein: described shell is provided with the heavy stand communicated with end face along its length at two ends, fixed head is provided with bottom heavy stand, fixed head is positioned at inside each heavy stand and is provided with through long slot bore, the both sides that fixed head is positioned at each heavy stand are provided with side channel hole, and described long slot bore and side channel hole are used for fixed head strain.
The periphery of described each power terminal is provided with the male and fomale(M&F) with epoxy resin layer strong bonded.
Through hole in described shell shell wall surrounding is L-shaped, and through hole one end communicates with shell upper surface, the other end communicates with inside the shell wall of outer casing underpart.
The overall height of described power model is at 9 ~ 12.5mm.
The present invention is covered cermet substrate and is connected to outer casing bottom and spacing by the limited post in shell, withstood by limited post and cover cermet substrate, to eliminate power model operationally, expanding with heat and contract with cold and the gap that produces with radiator because covering cermet substrate, ensureing proper heat reduction during chip operation.Threaded cylinder is established in each power terminal employing of power model of the present invention, its bottom welding is covering cermet substrate, because power terminal does not have bending structure, therefore power model is made to have lower stray inductance, due to the inductance of power model can be reduced, and power density and the functional reliability of power model can be improved further.Moreover, the cylindrical power model of the present invention can very low by Altitude control, in addition power model is not provided with copper soleplate, make power model overall height at 9 ~ 12.5mm, , total height and the encapsulation volume of power model can be effectively reduced, realize the miniaturization of power model, enclosure of the present invention is filled with soft silicon gel layer and is used for protecting semiconductor chip, and epoxy resin layer and shell, blend stop in shell and each power terminal and each control terminal are solidified into overall structure, add the constant intensity of each power terminal and each control terminal, each terminal can be stopped and cover cermet substrate junction and to come off the generation of problem.Shell of the present invention is provided with the through hole communicated with air in shell wall surrounding, by through hole to Silica hydrogel volumetric expansion and shrink produce stress and discharge, reduce power model operationally Silica hydrogel volumetric expansion and the stress shrinking generation, eliminate the damage of this stress to epoxy resin layer with this.The soldering-tin layer that power model of the present invention does not have copper soleplate and is connected with copper coin, the thermal resistance comparatively end of power model, reduces power loss, and can improve power model stability and reliability.The present invention adopts male and female face at the outer surface of power terminal, can increase the bonded area with epoxy resin layer, increase the adhesion of each power terminal.Shell of the present invention is provided with the heavy stand communicated with end face along its length at two ends, be positioned at inside each heavy stand at fixed head bottom heavy stand and be provided with through long slot bore, the both sides that fixed head is positioned at each heavy stand are provided with side channel hole, therefore long slot bore and side channel hole can be made for fixed head strain, certain elasticity is had by making fixed head, eliminate power model when installing and work, to the stress damage covering the generation of cermet substrate.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, embodiments of the invention are described in further detail.
Fig. 1 is the structural representation of the present invention's low inductance light and thin type power model.
Fig. 2 is the detonation configuration schematic diagram of the present invention's low inductance light and thin type power model.
Fig. 3 is the sectional structure schematic diagram of the present invention's low inductance light and thin type power model.
Fig. 4 is the structural representation of shell of the present invention.
Fig. 5 is that the A of Fig. 4 is to structural representation.
Wherein: 1-shell, 1-1-through hole, 1-2-long slot bore, 1-3-fixed head, 1-4-blend stop, 1-5-side channel hole, 1-6-limited post, 2-control terminal, 3-power terminal, 4-epoxy resin layer, 5-axle sleeve, 6-silicon gel layer, 7-cover cermet substrate, 8-semiconductor chip, 9-aluminium wire.
Embodiment
See the low inductance light and thin type power model shown in Fig. 1 ~ 5, comprise shell 1 and be welded on the semiconductor chip 8 covered on cermet substrate 7, multiple power terminal 3 and multiple control terminal 2 form circuit, can semiconductor chip 8 and power terminal 3 and disposable being welded on of control terminal 2 be covered on cermet substrate 7, this circuit is that the semiconductor chip 8 of this area routine and power device are connected to cover on cermet substrate 9 and form half-bridge circuit, chopper circuit, H-bridge circuit or full-bridge circuit, meets the different function requirements of power model.The present invention can directly in fixed heat sink by covering cermet substrate 7, copper soleplate is not provided with owing to covering cermet substrate 7 bottom, therefore power model has lower thermal resistance, its thermal resistance is about 4/5 of the high power model of 17mm and the high power model of 34mm, owing to decreasing the power loss of power model, stability and the reliability of power model can be improved.
See shown in Fig. 1 ~ 3, power terminal 3 of the present invention establishes threaded cylinder for endoporus, covering cermet substrate 7 is connected to bottom shell 1, power terminal 3 adopts endoporus to establish threaded copper sheathing, cylindrical bottom is fixed on to be covered on cermet substrate 7, can be weldingly fixed on and cover on cermet substrate 7, because power terminal 3 is without the need to bending structure, solve power terminal 3 to bend produced larger radian, and the technical problem of stray inductance cannot be reduced further, simultaneously also can very low by the Altitude control of power model, and then reduce power model height, achieve the miniaturization of power model.The periphery of each power terminal 3 of the present invention is provided with the male and fomale(M&F) with epoxy resin layer 4 strong bonded, this male and fomale(M&F) can adopt annular knurl process to be formed, other processing method is also adopted to be formed, the bonded area of power terminal 3 and epoxy resin can be increased by uneven of power terminal 3, namely the adhesion of power terminal 3 and epoxy resin is strengthened, when the power supply of outside and the exit of equipment are arranged on power terminal 3 by securing member, realize the input and output of power model.
See shown in Fig. 1 ~ 5, horizontal and vertical crossing blend stop 1-4 is provided with in the shell wall of shell 1 of the present invention, shell 1 is not only made to have good intensity, and when epoxy resin layer 4 is fixed with shell 1, can be increased and the contact-making surface of epoxy resin by blend stop 1-4, make together with epoxy resin layer 4 is set in reliably with shell 1 and power terminal 3.The present invention is provided with at least one limited post 1-6 in blend stop 1-4 bottom, limited post 1-6 on blend stop 1-4 withstands on and covers on cermet substrate 7, see Fig. 4, shown in 5, this limited post 1-6 can adopt two or more, this limited post 1-6 can be distributed on blend stop 1-4, after epoxy resin layer 4 is fixing with shell 1, limited post 1-6 on blend stop 1-4 is withstood on all the time to be covered on cermet substrate 7, when covering cermet substrate 7 because of the gap produced with radiator of expanding with heat and contract with cold, withstood by limited post 1-6 and cover cermet substrate 7, making to cover cermet substrate 7 fits on a heat sink, and proper heat reduction when ensureing each devices function.
As shown in Figure 3; the present invention is marked with soft silicon gel layer 6 in shell 1; to cover cermet substrate 7 by silicon gel layer 6 is on the one hand connected on shell 1; seal protection is carried out to covering the semiconductor chip 8 on cermet substrate 7 top, the aluminium wire 9 of bonding connection and device on the other hand by silicon gel layer 6; the present invention is provided with and air and the through hole 1-1 that communicates in shell wall surrounding at shell 1, and when this through hole 1-1 is used for Silica hydrogel volumetric expansion and shrinks, institute produces Stress Release.See shown in Fig. 1,2 and 4,5, through hole 1-1 in shell 1 shell wall surrounding of the present invention is L-shaped, through hole 1-1 one end communicates with shell 1 upper surface, the other end communicates with inside the shell wall of shell 1 bottom, communicating with silicon gel layer 6 of through hole 1-1 bottom and top communicates with air, therefore by multiple through hole 1-1 energy delivered power module operationally Silica hydrogel volumetric expansion and stress shrinking generation in time, therefore the damage of this stress to epoxy resin can be eliminated, to keep the reliability of power model work.
See Fig. 2, shown in 3, the each power terminal of the present invention 3 and each control terminal 2 are through silicon gel layer 6, epoxy resin layer 4 and shell 1, blend stop 1-4 in shell 1 and each power terminal 3 and each control terminal 2 are solidified into overall structure, epoxy resin layer 4 of the present invention maintains an equal level lower than shell 1 end face or with shell 1 end face, and the end face of power terminal 3 can hold face with epoxy resin layer 4 end face, but not higher than shell 1 end face, each control terminal 2 stretches out shell 1 end face 1.5 ~ 3.5mm, make the overall height of power terminal 3 can at 9 ~ 12.5mm, the overall height of power terminal 3 can at 10 ~ 11.8mm, owing to not establishing copper soleplate, outer cover height of the present invention can design at 7.5 ~ 10mm, can thus can encapsulation volume be reduced, shell 1 height of the present invention can have axle sleeve 5 in the corner of shell 1, this axle sleeve 5 can adopt metalwork, be connected with radiator by securing member to facilitate, power terminal 3 and control terminal 2 are fixedly connected with epoxy resin layer 4 by the present invention, and increase its reliability connected, power terminal 3 and control terminal 2 and the junction covering cermet substrate 7 can be stopped to come off the generation of problem.
See shown in Fig. 1,5, shell 1 of the present invention is provided with the heavy stand communicated with end face along its length at two ends, fixed head 1-3 is provided with bottom heavy stand, fixed head 1-3 is positioned at inside each heavy stand and is provided with through long slot bore 1-2, the both sides that fixed head 1-3 is positioned at each heavy stand are provided with side channel hole 1-5, long slot bore 1-2 and side channel hole 1-5 is used for fixed head 1-3 strain, by the strain of fixed head 1-3, eliminate power model when installing and work, to the stress damage covering cermet substrate 7 generation, improve the functional reliability of power model.
Claims (5)
1. one kind low inductance light and thin type power model, comprise shell (1) and be welded on the circuit covering the semiconductor chip (8) on cermet substrate (7), multiple power terminal (3) and multiple control terminal (2) and form, it is characterized in that: described power terminal (3) establishes threaded cylinder for endoporus, cylindrical bottom is fixed on to be covered on cermet substrate (7), covers cermet substrate (7) and is connected to shell (1) bottom, horizontal and vertical crossing blend stop (1-4) is provided with in the shell wall of described shell (1), blend stop (1-4) bottom is provided with at least one limited post (1-6), and the limited post (1-6) on blend stop (1-4) withstands on and covers on cermet substrate (7), soft silicon gel layer (6) is marked with in shell (1), shell (1) is provided with and air and the through hole (1-1) that communicates in shell wall surrounding, the Stress Release that produces when described through hole (1-1) expands for silicon gel layer (6) and shrinks, each power terminal (3) and each control terminal (2) are through silicon gel layer (6), epoxy resin layer (4) and shell (1), blend stop (1-4) in shell (1) and each power terminal (3) and each control terminal (2) are solidified into overall structure.
2. low inductance light and thin type power model according to claim 1, it is characterized in that: described shell (1) is provided with the heavy stand communicated with end face along its length at two ends, fixed head (1-3) is provided with bottom heavy stand, fixed head (1-3) is positioned at inside each heavy stand and is provided with through long slot bore (1-2), the both sides that fixed head (1-3) is positioned at each heavy stand are provided with side channel hole (1-5), and described long slot bore (1-2) and side channel hole (1-5) are for fixed head (1-3) strain.
3. low inductance light and thin type power model according to claim 1, is characterized in that: the periphery of described each power terminal (3) is provided with the male and fomale(M&F) with epoxy resin layer (4) strong bonded.
4. low inductance light and thin type power model according to claim 1, it is characterized in that: the through hole (1-1) in described shell (1) shell wall surrounding is L-shaped, through hole (1-1) one end communicates with shell (1) upper surface, the other end communicates with inside the shell wall of shell (1) bottom.
5. low inductance light and thin type power model according to claim 1, is characterized in that: the overall height of described power model is at 9 ~ 12.5mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510976938.1A CN105448846B (en) | 2015-12-23 | 2015-12-23 | Low inductance light and thin type power model |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510976938.1A CN105448846B (en) | 2015-12-23 | 2015-12-23 | Low inductance light and thin type power model |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105448846A true CN105448846A (en) | 2016-03-30 |
| CN105448846B CN105448846B (en) | 2017-12-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201510976938.1A Active CN105448846B (en) | 2015-12-23 | 2015-12-23 | Low inductance light and thin type power model |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018072057A1 (en) * | 2016-10-17 | 2018-04-26 | Littelfuse Electronics (Shanghai) Co., Ltd. | Embedded protection circuit module |
| CN115295498A (en) * | 2022-10-10 | 2022-11-04 | 合肥中恒微半导体有限公司 | High-temperature-resistant IGBT power module |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6424026B1 (en) * | 1999-08-02 | 2002-07-23 | International Rectifier Corporation | Power module with closely spaced printed circuit board and substrate |
| CN101523597A (en) * | 2006-12-27 | 2009-09-02 | 爱信艾达株式会社 | Electronic circuit device and method for manufacturing the same |
| CN104867887A (en) * | 2015-05-04 | 2015-08-26 | 嘉兴斯达半导体股份有限公司 | Two-layer encapsulated power module and packaging method |
| CN205248250U (en) * | 2015-12-23 | 2016-05-18 | 江苏宏微科技股份有限公司 | Low inductance light and thin type power module |
-
2015
- 2015-12-23 CN CN201510976938.1A patent/CN105448846B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6424026B1 (en) * | 1999-08-02 | 2002-07-23 | International Rectifier Corporation | Power module with closely spaced printed circuit board and substrate |
| CN101523597A (en) * | 2006-12-27 | 2009-09-02 | 爱信艾达株式会社 | Electronic circuit device and method for manufacturing the same |
| CN104867887A (en) * | 2015-05-04 | 2015-08-26 | 嘉兴斯达半导体股份有限公司 | Two-layer encapsulated power module and packaging method |
| CN205248250U (en) * | 2015-12-23 | 2016-05-18 | 江苏宏微科技股份有限公司 | Low inductance light and thin type power module |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018072057A1 (en) * | 2016-10-17 | 2018-04-26 | Littelfuse Electronics (Shanghai) Co., Ltd. | Embedded protection circuit module |
| CN110114868A (en) * | 2016-10-17 | 2019-08-09 | 上海利韬电子有限公司 | Embedded protection circuit module |
| CN110114868B (en) * | 2016-10-17 | 2023-06-27 | 上海利韬电子有限公司 | Embedded protection circuit module |
| CN115295498A (en) * | 2022-10-10 | 2022-11-04 | 合肥中恒微半导体有限公司 | High-temperature-resistant IGBT power module |
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| Publication number | Publication date |
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| CN105448846B (en) | 2017-12-05 |
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