阅读说明：本技术 一种GaN基射频器件及其封装方法 (A kind of GaN base radio-frequency devices and its packaging method ) 是由 王洪 周泉斌 姚若河 陈家乐 于 2019-08-13 设计创作，主要内容包括：本发明公开了一种GaN基射频器件及封装方法。所述器件包括DFN框架,所述DFN框架包括基岛、引脚栅极、引脚漏极和引脚源极,在电极方向上,引脚漏极位于基岛正面的左上方,引脚源极位于基岛正面的左下方,引脚栅极位于右下方,源极和栅极在同一水平线上；所述器件还包括GaN基射频芯片,GaN基射频芯片通过导电银浆固定在基岛上,GaN基射频芯片的内漏极、内源极和内栅极分别通过引线和DFN框架的引脚漏极、引脚源极和引脚栅极相应连接,分别作为器件漏极、器件源极和器件栅极；DFN框架外包裹有塑封料。所述封装方法选择小型化的DFN框架,通过塑料封装,使得生产成本降低、轻薄、加工简单、适合自动化生产,应用范围广泛。(The invention discloses a kind of GaN base radio-frequency devices and packaging methods.The device includes DFN frame, the DFN frame includes Ji Dao, pin grid, pin drain electrode and pin source electrode, in electrode direction, pin drain electrode is located at the positive upper left side in base island, pin source electrode is located at the positive lower left in base island, pin grid is located at lower right, and source electrode and grid are in the same horizontal line；The device further includes GaN base radio frequency chip, GaN base radio frequency chip is fixed on Ji Dao by conductive silver paste, interior drain electrode, interior source electrode and the inner grid of GaN base radio frequency chip pass through lead respectively and pin drain electrode, pin source electrode and the pin grid of DFN frame accordingly connect, respectively as device drain, device source electrode and device grids；DFN frame is wrapped with plastic packaging material.The DFN frame of the packaging method selection miniaturization, so that production cost reduces, frivolous, the processing is simple, is suitble to automated production, is had wide range of applications by Plastic Package.)

1. a kind of GaN base radio-frequency devices, which is characterized in that including DFN frame, the DFN frame include Ji Dao, pin grid, Pin drain electrode and pin source electrode, in electrode direction, pin drain electrode is located at the positive upper left side in base island, and pin source electrode is located at Ji Dao Positive lower left, pin grid are located at the positive lower right in base island, and pin source electrode and pin grid are in the same horizontal line；Institute Stating device further includes GaN base radio frequency chip, and GaN base radio frequency chip is fixed on Ji Dao by conductive silver paste, GaN base radio frequency chip Interior drain electrode, interior source electrode and inner grid pass through respectively lead and DFN frame pin drain electrode, pin source electrode and pin grid it is corresponding Connection, respectively as device drain, device source electrode and device grids；DFN frame is wrapped with plastic packaging material.

2. GaN base radio-frequency devices according to claim 1, which is characterized in that the Ji Dao is pentagonal Metal Substrate island； GaN base radio frequency chip is located at the middle of Ji Dao.

3. GaN base radio-frequency devices according to claim 1, which is characterized in that the lead is in 0.8mil ~ 2mil is golden Lead；It drains in connection and the radical of the lead of pin drain electrode is 1 ~ 8, the radical for connecting the lead of interior source electrode and pin source electrode is 2 ~ 8, the radical for connecting the lead of inner grid and pin grid is 1 ~ 4.

4. GaN base radio-frequency devices according to claim 1, which is characterized in that the GaN base radio frequency chip is lateral junction Structure, the area size of GaN base radio frequency chip are 800 μm of 1200 μ m, 800 μm ~ 2200 μ m, and interior drain electrode is located at GaN base radio frequency On the upside of chip, interior source electrode and inner grid are located on the downside of GaN base radio frequency chip, the cross arrangement in same level, of interior drain electrode Number is 1, and the number of interior source electrode is 2 ~ 5, and the number of inner grid is 1 ~ 4, and the area size of the interior source electrode of left and right ends is 145 μ ms 210 μm ~ 350 210 μm of μ ms, the area size of intermediate interior source electrode are 210 μm of 270 μ m, 210 μm ~ 410 μ m, inner grid Area size be 110 μm of 120 μ m, 110 μm ~ 160 μ m, the area size of interior drain electrode is 1200 μ m, 800 μm ~ 2200 μ m×800μm。

5. GaN base radio-frequency devices according to claim 1, which is characterized in that the region area of DFN frame is greater than GaN base The area of radio frequency chip, the size of DFN frame are 3mm × 3mm ~ 5mm × 5mm, the area of Ji Dao be 2.2mm × 2.6mm ~ 4.2mm×4.6mm。

6. GaN base radio-frequency devices according to claim 1, which is characterized in that DFN frame with a thickness of 150 ~ 200 μm, lead Electric silver paste with a thickness of 20 μm -40 μm, GaN base radio frequency chip with a thickness of 200 ~ 400 μm, lead bends to arc in connection Line, the height of the camber line are 90 μm ~ 100 μm, DFN frame thickness, conductive silver paste thickness, GaN base radio frequency chip thickness and are drawn The sum of line height is no more than 750 μm.

7. GaN base radio-frequency devices according to claim 1, which is characterized in that the interior source electrode of GaN base radio frequency chip, interior leakage Pole, inner grid include the aluminium layer arranged from top to bottom and layer gold, aluminium layer with a thickness of 200 ~ 500nm, layer gold with a thickness of 1 ~ 3 μm, the interior source electrode of GaN base radio frequency chip, interior drain electrode, inner grid are bonded with lead respectively.

8. GaN base radio-frequency devices according to claim 1, which is characterized in that the plastic packaging material is Halogen plastic packaging material.

9. the method for encapsulating the GaN base radio-frequency devices as described in any one of claim 1 to 8, which is characterized in that including walking as follows It is rapid:

(1) scribing: by scribing machine, selecting suitable blade and machine parameter according to chip road plan width and chip thickness, will The wafer of whole piece is divided into discrete single chip i.e. GaN base radio frequency chip；

(2) bonding die: by ink dot mode, using suitable silver paste head, suction nozzle, thimble, with conductive silver paste GaN base radio frequency chip Fixed on DFN frame Ji Dao；

(3) it toasts: putting dedicated baking oven into after completing bonding die, baking time 3 ~ 4 hours, temperature set 170 DEG C ~ 180 DEG C, in baking oven After vacuumizing, nitrogen is filled with as protective gas, it is ensured that the oxygen content in baking oven is maintained at 100ppm or less；Baking is completed Afterwards, chip need to be taken out when the temperature curve in case is reduced to room temperature, prevents chip residual temperature excessively high, be exposed to after taking out too early It will be easily oxidized in air；

(4) pressure welding: it is sent into press welder material track after the completion of baking, sets pressure, power, time-critical parameter, debugs Image recognition, according to pre-set cabling scenario, i.e. the inner grid of GaN base radio frequency chip is drawn out to pin grid by lead Pole, as the grid of device, interior drain electrode is drawn out to pin drain electrode by lead, and as the drain electrode of device, source electrode is drawn by lead Pin source electrode is arrived out, as the source electrode of device, obtains sample；

(5) pressure welding detects: by the test equipment of profession, testing GaN base radio frequency chip thrust, whether lead strain, which can reach, is wanted The range asked；Taking sample does crater test again, and sample is put into and is boiled into 75 ~ 85 DEG C of NaOH solution, pH range 8 ~ 9, to GaN After the metal layer on base radio frequency chip surface is dissolved, taking-up is rinsed well, observes GaN base radio frequency chip under an electron microscope The solder joint whether inside leaves after weighing wounded takes out cleaning, discovery does not have that is, by after the dissolution of GaN base radio frequency chip surface metal-layer Impression；

(6) plastic packaging: the specific clear mould of DFN injection molding machine is put into DFN note after 2 ~ 3 hours, the DFN frame where GaN base radio frequency chip Molding machine selects plastic packaging material compatible with DFN frame, and grinding tool is injected after hot melt, is taken out after fixed-type, by external high temperature membrane It tears, is put into specified DFN heat ageing baking oven and toasts 9 ~ 10 hours, the intracorporal residual steam of plastic packaging is discharged；

(7) be electroplated: by electrolysis oiling, cleaning, then high-pressure spraying, deoxidation, cleaning, preimpregnation, and then upper tin, cleaning, neutralization, Thermal cleaning, drying, are finally dried, and are taken out blanking bench, are carried out strip to steel band；(8) separation: floating screed is separated by dedicated DFN The frame of the DFN injection formed of entire row is cut using suitable width blade, then is separated into single finished product by type equipment.

10. the method for encapsulation GaN base radio-frequency devices according to claim 9, which is characterized in that in advance will with wafer lapping machine GaN base radio frequency chip is thinned to 200 ~ 400um.

Technical field

The invention belongs to microelectronics technologies, are related to semiconductor devices, specifically a kind of GaN base radio-frequency devices and Its packaging method.

Background technique

With the development of modern weapons equipment and aerospace, nuclear energy, the communication technology, automotive electronics, Switching Power Supply, half-and-half More stringent requirements are proposed for the performance of conductor device.As the Typical Representative of semiconductor material with wide forbidden band, GaN base material, which has, to be prohibited Bandwidth is big, electronics saturation drift velocity is high, critical breakdown strength is high, thermal conductivity is high, stability is good, corrosion-resistant, anti-radiation etc. Feature can be used for making high temperature, high frequency and high-power electronic device.In addition, GaN also has excellent characteristic electron, Ke Yihe AlGaN forms the AlGaN/GaN heterojunction structure of modulation doping, which can obtain the electricity higher than 1500cm2/Vs at room temperature Transport factor, and up to 3 × 107cm/s peak electron speed and 2 × 107cm/s saturated electrons speed, and obtain ratio The higher two-dimensional electron gas density of second generation compound semiconductor heterostructure is known as being the ideal for developing microwave power device Material.Therefore, the microwave power device based on AlGaN/GaN hetero-junctions is led in high-frequency, high-power wireless communication, radar etc. Domain has extraordinary application prospect.

GaN is the Typical Representative of third generation semiconductor material, has broad stopband, high breakdown electric field, high frequency, efficient etc. excellent Property, GaN base material and device are the directions of power electronics industry development, and cermet encapsulation is very common on the market at present Broadband GaN HEMT RF power device packing forms, only chip need to be welded on to shell heat sink surface, both by device source Pole is got up with flange electrical connection, while being gone out by the heat transfer that the flange of low thermal resistance can generate at work chip again It goes, is maintained at device within the scope of normal junction temperature and works, have the advantages that high reliablity.But this packing forms have it is following several A disadvantage:

(1) compared with Plastic Package, its processing temperature is high, cost performance is low etc.；

(2) automation of technique and slimming encapsulation ability are not as good as Plastic Package；

(3) brittleness is higher, is easy to cause stress damage.

Summary of the invention

It is an object of the invention to overcome the defect of above-mentioned prior art, the DFN frame of miniaturization is selected, plastic seal is passed through Dress so that production cost reduces, frivolous, the processing is simple, is suitble to automated production, and has wide range of applications, is current microelectronics More typical packaging method is used in industry.

The purpose of the present invention is realized at least through one of following technical solution.

The present invention provides a kind of GaN base radio-frequency devices, including DFN frame, the DFN frame includes Ji Dao, pin grid Pole, pin drain electrode and pin source electrode, in electrode direction, pin drain electrode is located at the positive upper left side in base island, and pin source electrode is located at The positive lower left in base island, pin grid are located at the positive lower right in base island, and source electrode and grid are in the same horizontal line；The device Part further includes GaN base radio frequency chip, and GaN base radio frequency chip is fixed on Ji Dao by conductive silver paste, GaN base radio frequency chip it is interior Drain electrode, interior source electrode and inner grid pass through lead respectively and pin drain electrode, pin source electrode and the pin grid of DFN frame accordingly connect It connects, respectively as device drain, device source electrode and device grids；DFN frame is wrapped with plastic packaging material.

Preferably, the Ji Dao is pentagonal Metal Substrate island；GaN base radio frequency chip is located at the middle of Ji Dao.

Preferably, the lead is the golden lead of 0.8mil~2mil；The lead of drain electrode and pin drain electrode in connection Radical is 1~8, and the radical for connecting the lead of interior source electrode and pin source electrode is 2~8, connects the lead of inner grid and pin grid Radical be 1~4.

Preferably, the GaN base radio frequency chip is transverse structure, and the area size of GaN base radio frequency chip is 1200 μ ms 800 μm~2,200 800 μm of μ ms, interior drain electrode are located on the upside of GaN base radio frequency chip, and interior source electrode and inner grid are located at GaN base radio frequency Chip underside, the cross arrangement in same level, the number of interior drain electrode are 1, and the number of interior source electrode is 2~5, the number of inner grid It is 1~4, the area size of the interior source electrode of left and right ends is 210 μm of 145 μ m, 210 μm~350 μ m, intermediate interior source electrode Area size is 210 μm of 270 μ m, 210 μm~410 μ m, and the area size of inner grid is 120 μ m, 110 μm~160 μ m 110 μm, the area size of interior drain electrode is 800 μm of 1200 μ m, 800 μm~2200 μ m.

Preferably, the region area of DFN frame is greater than the area of GaN base radio frequency chip, the size of DFN frame be 3mm × The area of 3mm~5mm × 5mm, Ji Dao are 2.2mm × 2.6mm~4.2mm × 4.6mm.

Preferably, DFN frame with a thickness of 150~200 μm, conductive silver paste with a thickness of 20 μm -40 μm, GaN base radio frequency Chip with a thickness of 200~400 μm, lead bends to camber line in connection, and the height of the camber line is 90 μm~100 μm, DFN The sum of frame thickness, conductive silver paste thickness, GaN base radio frequency chip thickness and lead height are no more than 750 μm.

Preferably, the interior source electrode of GaN base radio frequency chip, it is interior drain electrode, inner grid include the aluminium layer arranged from top to bottom and Layer gold, aluminium layer with a thickness of 200~500nm, layer gold with a thickness of 1~3 μm, the interior source electrode of GaN base radio frequency chip, interior drain electrode, Inner grid is bonded with golden lead respectively.

Preferably, the plastic packaging material is Halogen plastic packaging material.

The present invention also provides a kind of methods for encapsulating GaN base radio-frequency devices as described above, include the following steps:

(1) scribing: by scribing machine, suitable blade and machine is selected to join according to chip road plan width and chip thickness Number, is divided into discrete single chip i.e. GaN base radio frequency chip for the wafer of whole piece；

(2) bonding die: by ink dot mode, using suitable silver paste head, suction nozzle, thimble, with conductive silver paste GaN base radio frequency Chip is fixed on DFN frame Ji Dao；

(3) it toasting: putting dedicated baking oven into after completing bonding die, baking time 3~4 hours, temperature set 170 DEG C~180 DEG C,

After vacuumizing in baking oven, nitrogen is filled with as protective gas, it is ensured that the oxygen content in baking oven is maintained at 100ppm Below；After the completion of baking, chip need to be taken out when the temperature curve in case is reduced to room temperature, prevent chip residual temperature excessively high, mistake Exposure will be easily oxidized in air after early taking-up；

(4) pressure welding: being sent into press welder material track, set pressure, power, time-critical parameter after the completion of baking, adjusts Image recognition is tried, according to pre-set cabling scenario, i.e. the inner grid of GaN base radio frequency chip is drawn out to by lead to be drawn Foot grid, as the grid of device, interior drain electrode is drawn out to pin drain electrode by lead, and as the drain electrode of device, source electrode is by drawing Line is drawn out to pin source electrode, as the source electrode of device, obtains sample；

(5) pressure welding detects: by the test equipment of profession, testing GaN base radio frequency chip thrust, whether lead strain can reach To the range of requirement；Taking sample does crater test again, and sample is put into and is boiled into 75~85 DEG C of NaOH solution, and pH range 8~ 9, after the metal layer on GaN base radio frequency chip surface is dissolved, taking-up is rinsed well, observes GaN base under an electron microscope The solder joint left after whether weighing wounded inside radio frequency chip takes out cleaning that is, by after the dissolution of GaN base radio frequency chip surface metal-layer, It was found that no impression；

(6) plastic packaging: the specific clear mould of DFN injection molding machine was put into the DFN frame where GaN base radio frequency chip after 2~3 hours DFN injection molding machine selects plastic packaging material compatible with DFN frame, and grinding tool is injected after hot melt, is taken out after fixed-type, will be external High temperature membrane is torn, and is put into specified DFN heat ageing baking oven and is toasted 9~10 hours, the intracorporal residual steam of plastic packaging is discharged；

(7) be electroplated: by electrolysis oiling, cleaning, then high-pressure spraying, deoxidation, cleaning, preimpregnation, and then upper tin, cleaning, Neutralization, thermal cleaning, drying, are finally dried, and are taken out blanking bench, are carried out strip to steel band；(8) separation: floating screed passes through dedicated DFN The frame of the DFN injection formed of entire row is cut using suitable width blade, then is separated into single finished product by discretely-formed equipment.

Preferably, GaN base radio frequency chip is thinned to 200~400um with wafer lapping machine in advance.

Compared to the prior art, the invention has the advantages that and advantage:

(1) the GaN base radio-frequency devices of encapsulated moulding provided by the invention, by using advanced bilateral unleaded flat package DFN have low-down impedance, self-induction, the application of microwave or communication can be met, in addition light weight, it is thin, set without pin It counts and is suitble to portable use；

(2) simple process of the encapsulation of device provided by the invention, it is reproducible；

(3) present invention is that DFN used widely in the art encapsulates series, the easily scalable replacement using ground raw material.

Detailed description of the invention

Fig. 1 is a kind of schematic top plan view for GaN base radio-frequency devices that embodiment provides；

Fig. 2 a~Fig. 2 d is a kind of encapsulation preparation process schematic diagram for GaN base radio-frequency devices that embodiment provides；

In attached drawing: 1-GaN base radio frequency chip；2-DFN frame；201- Ji Dao；3- conductive silver paste；4- lead；The modeling of 5- Halogen Envelope material；Drain electrode in D1-；The drain electrode of D- pin；Source electrode in S1-；S- pin source electrode；G1- inner grid；G- pin grid.

Specific embodiment

Specific implementation of the invention is described further below in conjunction with attached drawing and example, but implementation and protection of the invention It is without being limited thereto, if it is noted that the following process or technological parameter for having not special detailed description, is those skilled in the art Member can visit prior art realization.