CN104051442A - Pulse power switch circuit packaging structure - Google Patents

Abstract

The invention discloses a pulse power switch circuit packaging structure which comprises first copper foil, a semiconductor pulse power switch chip, a capacitor, second copper foil, a copper cylinder, a magnetic switch and third copper foil. One end of the capacitor is welded to the third copper foil, the other end of the capacitor is welded to one end of the copper cylinder, the copper cylinder is perpendicular to the center axis of the capacitor, the other end of the copper cylinder penetrates through the center of the magnetic switch and is welded to one end of the second copper foil, the second copper foil is parallel to the center axis of the capacitor, an anode of the semiconductor pulse power switch chip is welded to the face, close to the capacitor, at the other end of the second copper foil, and a cathode of the semiconductor pulse power switch chip is welded to the first copper foil. According to the structure, multiple peripheral devices and a semiconductor pulse power switch are packaged together to form a whole module, the size is small, functions are complete, stray parameters are reduced, peripheral circuits are simplified, the novel packaging technology is adopted, stability of power devices is enhanced, and cost is reduced.

Description

A kind of pulse power switch circuit encapsulating structure

Technical field

The invention belongs to integration packaging technical field, more specifically, relate to a kind of pulse power switch circuit encapsulating structure, be mainly used in low inductance Pulased power supply unit.

Background technology

Pulse Power Techniques are a kind of the little energy of power density to be compressed after storage, the technology discharging with high power within the extremely short time.It starts from 1962, and flourish through many decades become an important engineering application technology, military and industrially have important scientific meaning and a using value.For a pulse power system, core comprises circuit topology, insulation and the large technology of switch three.

Common semiconductor pulse power switch has pulse thyristor, gate level turn-off thyristor (Gate Turn-off Thyristor, GTO), igbt (Insulated Gate Bipolar Transistor, IGBT), power metal oxide semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET), reverse switch transistor (Reversely Switched Dynistor, RSD) etc.

The application of high on-state current-rising-rate (di/dt) in Pulse Power Techniques is a lot, such as excimer laser, electromagnetic railgun etc.They are less demanding for voltage, but harsher to the requirement of electric current, and desirable electric current is generally trapezoidal pulse electric current, and its peak value requires hundreds of kA to MA, and the peak value rise time short (being generally microsecond rank), duration of peak value reaches a millisecond magnitude.Generally speaking, semiconductor pulse power switch all need to increase buffer circuit to prevent the too high device failure that causes of di/dt in circuit.

Traditional pulse power circuit is generally to use wire or copper bar etc. to connect each discrete device, and the connection of each device is by bolt, and the Metal Contact of junction relies on extruding force to keep, and the stray parameter bringing is large and be difficult to calculate.In addition, along with the class requirement of the di/dt in paired pulses power circuit, ceiling voltage, repetition rate etc. is more and more higher, the impact that parasitic parameter brings is increasing, and it is quite complicated that the analysis and calculation of circuit also becomes, and also can be with the unpredicted problem of serving.

Summary of the invention

Above defect or Improvement requirement for prior art, the invention provides a kind of pulse power switch circuit encapsulating structure, a plurality of peripheral components and semiconductor pulse power switch are packaged together and form an integral module, volume is little, perfect in shape and function, has reduced stray parameter and has simplified peripheral circuit, adopts novel encapsulated technique, the stability that has strengthened power device, has reduced cost.Contrast traditional discharge loop, the di/dt magnitude that pulse power switch circuit of the present invention reaches can be promoted to original twice.

For achieving the above object, according to one aspect of the present invention, a kind of pulse power switch circuit encapsulating structure is provided, has it is characterized in that, comprised the first Copper Foil, semiconductor pulse power switch chip, electric capacity, the second Copper Foil, copper post, magnetic switch and the 3rd Copper Foil; Described the 3rd Copper Foil is welded in one end of described electric capacity, the other end welds one end of described copper post, described copper post is vertical with the central shaft of described electric capacity, the other end of described copper post is soldered to one end of described the second Copper Foil through the center of described magnetic switch, the central axes of described the second Copper Foil and described electric capacity, its other end welds the anode of described semiconductor pulse power switch chip near the one side of described electric capacity, the first Copper Foil described in the cathode weld of described semiconductor pulse power switch chip.

According to another aspect of the present invention, a kind of pulse power switch circuit encapsulating structure is provided, it is characterized in that, comprise semiconductor pulse power switch chip, electric capacity, magnetic switch, a DBC copper layer piece, the 2nd DBC copper layer piece and the 3rd DBC copper layer piece; Described the 2nd DBC copper layer piece is through the center of described magnetic switch, the two ends of described electric capacity are welded on respectively on a described DBC copper layer piece and described the 2nd DBC copper layer piece, the anodic bonding of described semiconductor pulse power switch chip is connected on described the 2nd DBC copper layer piece, its negative electrode is welded on described the 3rd DBC copper layer piece by Copper Foil, and described magnetic switch is between described semiconductor pulse power switch chip and described electric capacity.

Preferably, described semiconductor pulse power switch chip is gate level turn-off thyristor or reverse switch transistor.

In general, the above technical scheme of conceiving by the present invention compared with prior art, has following beneficial effect:

1, by semiconductor pulse power switch together with the loop device integration packagings such as capacitor, magnetic switch, by structure and the position relationship of each element of appropriate design, make the annexation between each element more firm, wire length is minimum, encapsulating structure is compacter, thereby make the distribution of stray parameter also be optimized and reduce, promoted the characteristics such as its di/dt, make loop under low voltage condition, obtain the current-rising-rate of more increasing than conventional circuit.

2, adopt solder reflow process and Copper Foil to carry out bonding, reduced conventional semiconductors pulse power switch and adopted the problems such as the electric current that aluminum wire bonding technology is brought distributes inequality, and stray inductance is excessive.

3, by integration packaging, reduced the volume of whole device, simplified circuit connecting mode, reduced the difficulty that user uses semiconductor pulse power switch.

Accompanying drawing explanation

Fig. 1 is the pulse power switch circuit encapsulating structure schematic diagram of the embodiment of the present invention 1;

Fig. 2 is the stereogram of the pulse power switch circuit encapsulating structure of the embodiment of the present invention 1;

Fig. 3 is the pulse power switch circuit encapsulating structure schematic diagram of the embodiment of the present invention 2;

Fig. 4 is the stereogram of the pulse power switch circuit encapsulating structure of the embodiment of the present invention 2;

Fig. 5 is the circuit theory diagrams of the pulse power switch circuit encapsulating structure of the embodiment of the present invention.

In institute's drawings attached, identical Reference numeral is used for representing identical element or structure, wherein: 1-the first Copper Foil, 2-semiconductor pulse power switch chip, 3-electric capacity, 4-the second Copper Foil, 5-copper post, 6-magnetic switch, 7-the 3rd Copper Foil, 8-the one DBC copper layer piece, 9-the 2nd DBC copper layer piece, 10-Copper Foil, 11-the 3rd DBC copper layer piece.

Embodiment

In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.In addition,, in each execution mode of described the present invention, involved technical characterictic just can not combine mutually as long as do not form each other conflict.

Integrated circuit technique the application success of microelectronics technology changed All Around The World, the present invention is applied to pulse power field by the thinking of development of integrated circuit technique, pass through integrated technology, the technical barrier of the aspects such as components and parts, circuit, control, electromagnetism, material, heat transfer and main design work are solved at integration module inner, volume and the wiring length of whole device have been reduced, effectively reduce the stray parameter that circuit itself brings, thereby reduced the impact that stray parameter brings.

Embodiment 1

As depicted in figs. 1 and 2, pulse power switch circuit encapsulating structure comprises: the first Copper Foil 1, semiconductor pulse power switch chip 2, electric capacity 3, the second Copper Foil 4, copper post 5, magnetic switch 6 and the 3rd Copper Foil 7.Magnetic switch 6 is circular ring structure.One end welding the 3rd Copper Foil 7 of electric capacity 3, one end of other end soldering copper post 5, copper post 5 is vertical with the central shaft of electric capacity 3, the other end of copper post 5 is soldered to one end of the second Copper Foil 4 through the center of magnetic switch 6, the central axes of the second Copper Foil 4 and electric capacity 3, its other end welds the anode of semiconductor pulse power switch chip 2 near the one side of electric capacity 3, one end of cathode weld first Copper Foil 1 of semiconductor pulse power switch chip 2, and the other end bending of the first Copper Foil 1 is to form electrode.The first Copper Foil 1 and the 3rd Copper Foil 7 are for external load.

Embodiment 2

As shown in Figure 3 and Figure 4, pulse power switch circuit encapsulating structure comprises: semiconductor pulse power switch chip 2, electric capacity 3, magnetic switch 6, a DBC copper layer piece 8, the 2nd DBC copper layer piece 9, Copper Foil 10 and the 3rd DBC copper layer piece 11.Copper (Direct Bonding Copper, DBC) layer is directly covered in design in advance, obtains a DBC copper layer piece 8, the 2nd DBC copper layer piece 9 and the 3rd DBC copper layer piece 11.Magnetic switch 6 is circular ring structure, the 2nd DBC copper layer piece 9 is through the center of magnetic switch 6, the two ends of electric capacity 3 are welded on respectively on a DBC copper layer piece 8 and the 2nd DBC copper layer piece 9, the anodic bonding of semiconductor pulse power switch chip 2 is connected on the 2nd DBC copper layer piece 9, and negative electrode is welded on the 3rd DBC copper layer piece 11 by Copper Foil 10.Magnetic switch 6 is between semiconductor pulse power switch chip 2 and electric capacity 3.The one DBC copper layer piece 8 and the 3rd DBC copper layer piece 11 are for external load.

In above-described embodiment, the welding of semiconductor pulse power switch chip and copper adopts solder reflow process, and scolding tin adopts leaded class scolder, and material is softer, is conducive to reduce thermal stress; Copper thickness determines according to circuit parameter; Electric capacity adopts common solder technology with being connected of copper.Semiconductor pulse power switch is Si main pulse thyristor, GTO or RSD, can be also SiC base semiconductor power device.

The circuit theory diagrams of pulse power switch circuit encapsulating structure as shown in Figure 5, the anode of semiconductor pulse power switch T connects one end of magnetic switch SL by the stray inductance L in circuit (not having concrete inductance coil in encapsulating structure inside), the other end of magnetic switch SL connects one end of capacitor C, the negative electrode external load Z of the other end of capacitor C and semiconductor pulse power switch T.The two ends external power supply of capacitor C, the external preliminary filling circuits for triggering in two ends of semiconductor pulse power switch.

For RSD device, there is following relation with the di/dt flowing through in its preliminary filling electric current:

$Q_c={\∫}_0^{t_c}{I}_c\mathrm{dt}\≥A\·\mathrm{di}/\mathrm{dt}$

In formula, I _cfor preliminary filling electric current, t _cfor pre-charging time, A is the structural parameters of RSD device, is about 0.5 * 10 ^-12～1.5 * 10 ^-12s ², di/dt is that the current-rising-rate that flows through RSD is main circuit current climbing.For preliminary filling circuits for triggering, under identical pre-charging time, the di/dt of major loop increase increases preliminary filling electric current, and precharge flow need to become greatly, even likely has influence on major loop.

Extend pre-charging time and can reduce the requirement to precharging circuit, but can cause like this switching losses to increase, even if do not consider switching losses, magnetic switch voltage one regularly, extending pre-charging time is generally to rely on the magnetic core area that increases magnetic switch to realize, and in engineering reality often to magnetic switch finite volume system.

For magnetic switch, its role is at preliminary filling circuits for triggering during to RSD preliminary filling electric current, blocking-up main circuit current, its Xining t _smeet following relation:

${\mathrm{\ΔBN}}_k{A}_k={\∫}_0^{t_s}{V}_k\mathrm{dt}$

Wherein, Δ B is magnetic switch coil flux variable quantity, N _kfor coil turn, A _kfor magnetic core area, V _kfor magnetic switch voltage.

When design module internal components parameter, need to consider inner parameter and external parameter, preferentially according to stray induced voltages V=Ldi/dt, calculate major loop maximum current slew rate, according to it, calculate preliminary filling electric current and pre-charging time again, need to consider Xining and the magnetic switch volume of magnetic switch simultaneously, thereby determine final pre-charging time, and further determine the relevant parameter of precharging circuit.

Those skilled in the art will readily understand; the foregoing is only preferred embodiment of the present invention; not in order to limit the present invention, all any modifications of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.

Claims (3)

1. a pulse power switch circuit encapsulating structure, it is characterized in that, comprise the first Copper Foil (1), semiconductor pulse power switch chip (2), electric capacity (3), the second Copper Foil (4), copper post (5), magnetic switch (6) and the 3rd Copper Foil (7);

Described the 3rd Copper Foil (7) is welded in one end of described electric capacity (3), the other end welds one end of described copper post (5), described copper post (5) is vertical with the central shaft of described electric capacity (3), the other end of described copper post (5) is soldered to one end of described the second Copper Foil (4) through the center of described magnetic switch (6), the central axes of described the second Copper Foil (4) and described electric capacity (3), its other end welds the anode of described semiconductor pulse power switch chip (2) near the one side of described electric capacity (3), the first Copper Foil (1) described in the cathode weld of described semiconductor pulse power switch chip (2).

2. a pulse power switch circuit encapsulating structure, it is characterized in that, comprise semiconductor pulse power switch chip (2), electric capacity (3), magnetic switch (6), a DBC copper layer piece (8), the 2nd DBC copper layer piece (9) and the 3rd DBC copper layer piece (11);

Described the 2nd DBC copper layer piece (9) is through the center of described magnetic switch (6), the two ends of described electric capacity (3) are welded on respectively on a described DBC copper layer piece (8) and described the 2nd DBC copper layer piece (9), the anodic bonding of described semiconductor pulse power switch chip (2) is connected on described the 2nd DBC copper layer piece (9), it is upper that its negative electrode is welded on described the 3rd DBC copper layer piece (11) by Copper Foil (10), and described magnetic switch (6) is positioned between described semiconductor pulse power switch chip (2) and described electric capacity (3).

3. pulse power switch circuit encapsulating structure as claimed in claim 1 or 2, is characterized in that, described semiconductor pulse power switch chip is gate level turn-off thyristor or reverse switch transistor.