WO2016086769A1 - Csp type mems packaging piece based on customised lead frame and production method therefor - Google Patents

Abstract

A CSP type MEMS packaging piece based on a customised lead frame and a production method therefor. An MEMS chip (1) with protrusions is mounted on an upper surface (6) of an inner pin of a packaging piece in an inverted mode, and the MEMS chip (1) is connected to a bonding pad (15) on a back face of the inner pin; a first VGA amplifier chip (8) is pasted on the MEMS chip (1), and the first VGA amplifier chip (8) is connected to the upper surface (6) of the inner pin; a bottom face pin metal layer (14) is arranged on a bottom face of a bottom face pin (12); and a first plastic packaging body (10) is arranged on the lead frame in a plastic packaging mode, all devices are arranged in the first plastic packaging body (10) in a plastic packaging mode, and only the bottom face pin metal layer (14) is exposed out of the first plastic packaging body (10). The CSP type MEMS packaging piece based on the customised lead frame is manufactured through the procedures of manufacturing a lead frame, thinning and scribing a wafer, pasting a chip, welding wires, carrying out plastic packaging and the like. The packaging piece can eliminate interference, ensure the signal detection precision of the MEMS chip, reduce the influence of additional and parasitic inductance, capacitance and resistance of the packaging piece itself and environmental interference on signals, and prevent output signals from being intercepted, distorted or gained.

Description

CSP type MEMS package based on custom lead frame and production method thereof Technical field

The invention belongs to the technical field of semiconductor manufacturing, and relates to a CSP type MEMS package based on a customized lead frame, and to a method for producing the package.

Background technique

CSP (Chip Scale Package, the same below), chip-scale package, this package is a thin, micro package developed on the basis of TSOP and BGA. CSP can realize a package with a ratio of chip area to package area exceeding 1..1.14, and its package area is about 1/3 of that of ordinary BGA, which is only 1/6 of the package area of TSOP memory chip. CSP is not only small in size, but also thinner. The most effective heat dissipation path from the substrate to the heating element is only 0.2mm, which greatly improves the reliability of the memory chip for a long time running, the line impedance is significantly reduced, and the chip speed is also greatly increased. The range is increased.

In MEMS packages such as DIP and SOP, the main problem is how to eliminate interference and ensure the detection accuracy and gain of the MEMS chip. Although the MEMS chip has a strong signal detection function, in actual use, it is affected by the additional inductance, capacitance, resistance and environmental dry deflection signal of the package itself, causing the output signal to be cut off or distorted.

Summary of the invention

The object of the present invention is to provide a CSP type MEMS package based on a custom lead frame, which is not affected by the additional inductance, capacitance, resistance and environmental dry deflection signals of the package itself, and avoids the output signal being cut off or distorted.

Another object of the present invention is to provide a method of producing the above MEMS package.

In order to achieve the above object, the technical solution adopted by the present invention is: a CSP type MEMS package based on a custom lead frame, including a lead frame, wherein the inner pin of the lead frame is connected to the bottom surface pin, and the upper surface of the inner pin is inverted. Mounted with a bumped MEMS chip, the bump on the MEMS chip is connected to the back pad of the inner pin through the second bonding wire; the first VGA amplifier chip is pasted on the MEMS chip, and the first VGA amplifier chip passes the first The bonding wire is connected to the upper surface of the inner pin; the first groove and the second groove are arranged in parallel along a direction perpendicular to the line connecting the bottom rows of the two rows, and the bottom pin is away from the opposite ends of the upper surface of the inner pin. The bottom surface of the bottom surface of the bottom pin is provided with a metal layer of the bottom surface; the first plastic body is molded on the lead frame, and all the components are molded in the first plastic body, and only the metal layer of the bottom surface is exposed to the first plastic body.

Another technical solution adopted by the present invention is: a production method of the above-mentioned custom lead frame-based CSP type MEMS package, which is specifically carried out according to the following steps:

Step 1: Make a multi-row matrix carrierless wing gull-type internal CSP lead frame with the front and back sides of the inner leads in addition to electroplated copper, silver or nickel-plated palladium-plated pads, or flip-chip according to plating The package needs to be plated with a UBM metal layer;

The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

Step 2: On the adhesive sheet bonding machine, first place the first adhesive sheet on the front end surface of the lead pin on the lead frame, and then place the MEMS chip in reverse on the multi-row matrix of the first adhesive sheet. The front side of the inner lead of the CSP lead frame is lifted, and all the MEMS chip 1 is baked, and then baked in a section, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and then heated for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 ° minutes to remove the temperature to 70 ° C; the anti-separation process is used in the segment baking process; on the ball welder, the semi-finished multi-row matrix CSP after baking The lead frame is reversely fed, and the back pad of the upturned inner pin of the multi-row matrix CSP lead frame wing gull type is reversed to the second radiant wire of the pad on the MEMS chip; the film is stuck in the film On the chip machine, the semi-assembled multi-row matrix CSP lead frame with the second bonding wire is fed, and the second adhesive sheet is drawn on the back of the MEMS chip, and the first VGA amplifier chip automatically picked up by the device is accurately placed in the film. The back side of the MEMS chip that has been glued, bonding the entire first VGA amplifier After the chip, the same segmental baking is used, and the anti-separation layer process is adopted in the segment baking process; on the ball bonding machine, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip is bonded is forwarded. The first bonding wire is drawn from the pad on the first VGA amplifier chip to the front pad of the multi-row matrix CSP lead frame wing gull type upturned inner lead; after the bonding wire, the expansion coefficient is selected Α1≤1, water absorption rate ≤0.30%, plastic packaging material plastic seal, the punching rate is controlled at 5%, no void and separation layer, post-curing at 150 °C for 5 hours; if the bottom pin is not plated in the frame production Nickel palladium gold or pure gold, plating blunt tin, blunt tin layer thickness 7.62 ~ 15.24μm, and baking at 175 ° C, 1 hour to prevent whisker growth; after laser marking, cutting separation, testing, tape, A CSP type MEMS package based on a custom lead frame is prepared; if the bottom surface of the bottom pin is plated with nickel palladium gold or pure gold, no pure tin plating, direct laser marking, shear separation, testing, tape making, A CSP type MEMS package based on a custom lead frame;

The MEMS package of the invention can eliminate the dry deflection, ensure the detection precision of the MEMS chip signal, reduce the additional and parasitic inductance of the package itself, the influence of the capacitance, the resistance and the dry deflection of the environment on the signal, and prevent the output signal from being cut off and distorted. Or gain. In addition to the MEMS chip, this package incorporates a wide-band, low-noise, low-distortion, high-gain-precision voltage-controlled VGA amplifier (Variable Gain Amplifire, VGA amplifier) chip with a variable attenuation. The device, the gain control interface and a fixed gain amplifier are three parts, which can automatically adjust the frequency and attenuate and amplify the signal detected by the MEMS device, but without distortion. It is often used in RF automatic gain amplifier, video gain control, A/D. Converter range extension and signal detection system.

DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view showing a first embodiment of a MEMS package of the present invention.

2 is a cross-sectional view showing a second embodiment of the MEMS package of the present invention.

3 is a cross-sectional view showing a third embodiment of the MEMS package of the present invention.

4 is a cross-sectional view showing a fourth embodiment of the MEMS package of the present invention.

Figure 5 is a cross-sectional view showing a fifth embodiment of the MEMS package of the present invention.

In the figure: 1. MEMS chip, 2. first adhesive sheet, 3. inner pin lower surface, 4. first groove, 5. inner pin, 6. inner pin upper surface, 7. first key Alignment, 8. First VGA amplifier chip, 9. Second adhesive sheet, 10. First plastic package, 11. Front pad, 12. Back surface pin, 13. Second groove, 14. Bottom pin Metal layer, 15. back pad, 16. second bond wire, 17. MEMS cover, 18. second plastic body, 19. MEMS cover opening, 20. first film, 21. second VGA amplifier chip, 22. chip bump, 23. first UBM, 24. MEMS partition, 25. second film, 26. second UBM, 27. third VGA amplifier chip.

detailed description

The invention will be described in detail below with reference to the drawings and specific embodiments.

The structure of all embodiments of the MEMS package of the present invention adopts the same multi-row matrix leadless CSP custom lead frame suitable for CSP package, and the custom lead frame has an external dimension of 259.00 mm×79.00 mm, and according to the package The optimal size of the design frame (8 to 12 rows) and the number of package units (120 to 240), the inner leads in the custom lead frame are lifted up into a gull-wing shape, and the upper lead surface of the inner pin And the lower surface of the pin are parallel to the horizontal plane, and the front and back surfaces of the upper lead surface are plated with a metal layer for the bonding wire; the bottom surface of the lower pin in the custom lead frame is provided with a groove for the plastic sealing The material is embedded so that the plastic body is firmly bonded to the lead frame, and a tin layer or a copper layer or a gold layer is plated on the bottom surface of the lower pin as the lead-in end of the signal and power source.

As shown in FIG. 1 , a first embodiment of the MEMS package of the present invention is a MEMS package structure without a cap plate, including a custom lead frame, and an inner pin 5 and a bottom pin 12 in the custom lead frame. Connected, the upper surface 6 of the inner pin is bonded to the MEMS chip 1 through the first adhesive sheet 2, and the MEMS chip 1 is a bumped chip. The MEMS chip 1 is flipped on the upper surface 6 of the inner lead, on the MEMS chip 1. The bump is connected to the back pad 15 of the inner lead through the second bonding wire 16; the first VGA amplifier chip 8 is pasted on the MEMS chip 1 through the second adhesive sheet 9, and the soldering on the first VGA amplifier chip 8 The disk is connected to the front pad 11 on the upper surface 6 of the inner lead through the first bonding wire 7; in the direction perpendicular to the line connecting the pins 12 of the bottom row of the two rows, the bottom pin 12 is away from the upper surface 6 of the inner pin. The sides are arranged in parallel The first groove 4 and the second groove 13, the first groove 4 on the bottom row of pins 12 faces the other row of bottom pins 12, and the bottom surface of the bottom surface of the bottom pin 12 is provided with a bottom pin metal layer 14; First VGA amplifier chip 8, second adhesive sheet 9, second bonding wire 16, front pad 11, inner pin upper surface 6, MEMS chip 1, first adhesive sheet 2, inner pin lower surface 3 The first bonding wire 7, the back surface pad 15, the first recess 4, the second recess 13, the inner lead 5, the upper surface of the bottom surface pin 12, and the bottom surface pin metal layer 14 constitute the entire circuit. The MEMS chip 1, the first bonding wire 7, the first VGA amplifier chip 8, the second bonding wire 16, the inner lead 5, the front pad 11, the back surface pad 15, and the bottom pin metal layer 14 constitute a power supply for the circuit. And signal channels. The lead frame is molded with a first molding body 10, a bottom surface pin 12, an inner lead 5, a first bonding wire 7, a second bonding wire 16, a MEMS chip 1, a first VGA amplifier chip 8, and a first groove. 4 and the second recess 13 are both located in the first molding body 10, and only the bottom surface pin metal layer 14 is exposed outside the first molding body 10.

As shown in FIG. 2, a second embodiment of the MEMS package of the present invention is a MEMS chip and VGA amplifier chip stacked package structure with a bottom cover plate, and the structure and the MEMS package in the first embodiment. The structure of the components is basically the same, and the difference between the two is that in the second embodiment, the MEMS cover plate 17 is disposed between the two rows of the bottom surface pins 12, and one side of the MEMS cover plate 17 and one row of the bottom surface pins 12 are provided. The first recess 4 is fixed, and the MEMS cover 17 is provided with a MEMS cover opening 19; the MEMS cover 17, the inner lead 5 and the MEMS chip 1 are integrally molded with a transparent second plastic body 18 ;

The first molding body 10, the second bonding wire 15, the first VGA amplifier chip 8, the second adhesive sheet 9, the inner lead upper surface 6, the front surface pad 11, the inner lead 5, and the bottom surface pin 12 Surface, first groove 4, second molding body 18, MEMS chip 1, first adhesive sheet 2, first bonding wire 7, back surface pad 15, inner pin lower surface 3, second groove 13, The MEMS cover plate 17 and the MEMS cover opening 19 constitute the entire circuit. The MEMS chip 1, the first VGA amplifier chip 8, the second bonding wire 16, the inner lead 5, the front pad 11, the back pad 15 and the bottom pin metal layer 14 constitute a power supply and signal path of the circuit.

As shown in FIG. 3, a third embodiment of the MEMS package of the present invention includes a custom lead frame in which the inner lead 5 is connected to the bottom surface pin 12, and the inner lead upper surface 6 passes through the first adhesive. The diaphragm 20 is pasted with the MEMS chip 1. The pads on the MEMS chip 1 are connected to the front pads 11 on the upper surface 6 of the inner leads through the first bonding wires 7, and the upper surface 6 of the inner leads is provided with a MEMS partition. 24, the top end of the MEMS partition wall 24 of the two rows of inner pins 5 are connected by the MEMS cover plate 17, and the MEMS cover plate 17 is provided with the MEMS cover opening 19, the MEMS partition wall 24, the MEMS cover plate 17, and the inner lead pins. The upper surface 6 and the MEMS chip 1 enclose a cavity. The first bonding wire 7 and the front surface pad 11 are both located in the cavity, and the cavity is molded with a transparent second molding body 18; the inner pin lower surface 3 passes through The first UBM 23 is bonded to the second VGA amplifier chip 21, and the first UBM 23 is bonded to the chip bump 22 on the second VGA amplifier chip 21, that is, the chip bump 22 on the second VGA amplifier chip 21 faces upward. a first groove 4 is disposed in parallel along a direction perpendicular to the line connecting the two rows of the bottom surface pins 12, and a side of the bottom surface pin 12 away from the end of the upper surface 6 of the inner lead The second recess 13 has a first recess 4 on the bottom surface of the row of pins 12 facing the other row of bottom pins 12, and a bottom surface of the bottom surface of the bottom pin 12 is provided with a bottom metal layer 14; the custom lead frame is molded with a plastic The first molding body 10, except for the cavity, the MEMS cover plate 17, and the bottom pin metal layer 14, is molded in the first molding body 10.

First molding body 10, MEMS cover plate 17, cover opening 19, MEMS partition wall 24, lead upper surface 6, second VGA amplifier chip 21, chip bump 22, first UBM 23, front pad 11, The upper surfaces of the inner lead lower surface 3, the inner lead 5, the first recess 4, the second recess 13, and the bottom surface lead 12 constitute the package circuit as a whole. The MEMS chip 1, the first bonding wire 7, the front pad 11, the second VGA amplifier chip 21, the chip bump 22, the first UBM 23, the inner lead 5, and the bottom pin metal layer 14 constitute a power supply and signal of the circuit. The channel and the output end are firmly connected, and the high frequency performance is good.

As shown in FIG. 4 , a fourth embodiment of the MEMS package of the present invention is a bottom cover with a MEMS chip and a VGA amplifier chip package on both sides of the inner lead, and the structure and the second The structure of the embodiment is basically the same, and the difference between the two is: in the fourth embodiment, the MEMS chip 1 is pasted on the inner pin lower surface 3 through the first adhesive film 20, and the pad on the MEMS chip 1 passes. The second bonding wire 16 and the back on the lower surface 3 of the inner pin The surface pads 15 are connected; the first VGA amplifier chip 8 is pasted on the upper surface 6 of the inner lead via the second adhesive film 25, and the pads on the first VGA amplifier chip 8 are soldered to the front surface through the first bonding wires 7. The disks 11 are connected; the custom lead frame uses a multi-row matrix CSP nickel-palladium gold plating frame.

First molding body 10, second bonding wire 16, first VGA amplifier chip 8, second adhesive film 25, front surface pad 11, inner pin upper surface 6, inner lead 5, first adhesive film 20 The MEMS chip 1, the back surface pad 15, the first bonding wire 7, the upper surface of the bottom surface pin 12, the second molding body 18, the first recess 4, and the second recess 13 constitute the entire circuit. The MEMS chip 1, the first bonding wire 7, the first VGA amplifier chip 8, the front surface pad 11, the back surface pad 15, the inner lead 5, and the bottom metal layer 14 constitute a power supply and signal path of the circuit, and the output end is firmly contacted. .

As shown in FIG. 5, a fifth embodiment of the CSP package of the present invention is a package of a two-sided flip-chip VGA amplifier chip and a front-side stacked MEMS chip, including a custom lead frame, and the custom lead frame is adopted. A multi-row matrix CSP nickel-palladium gold electroplating frame in which the inner lead 5 is tilted up to form a gull-wing type, and the upper surface 6 of the inner lead is mounted with a third VGA amplifier chip 27, that is, a third VGA amplifier chip 27 The chip bump is bonded to the inner lead upper surface 6 through the second UBM 26, and the upper surface of the third VGA amplifier chip 27 is bonded to the MEMS chip 1 through the second adhesive film 25, and the pad on the MEMS chip 1 passes. The first bonding wire 7 is connected to the front surface pad 11 on the upper surface 6 of the inner lead; the second VGA amplifier chip 21 is mounted on the lower surface 3 of the inner pin, that is, the chip bump on the second VGA amplifier chip 21. Point 22 is bonded to the lower surface 3 of the inner lead by the first UBM 23; parallel to the sides perpendicular to the line connecting the pins 12 of the bottom row, and the sides of the bottom pin 12 away from the end of the upper surface 6 of the inner lead are arranged in parallel The first groove 4 and the second groove 13 are oriented toward the first groove 4 on the bottom surface of the pin 12 A row of bottom surface pins 12, a bottom surface pin layer 12 is provided on the bottom surface of the bottom surface pins 12; a MEMS chip 1, a first bonding wire 7, a second VGA amplifier chip 21, an inner pin 5, and a front pad 11 The back pad 15 and the bottom pin metal layer 14 form the power and signal path of the circuit. The lead frame is molded with a first molding body 10, a bottom surface pin 12, an inner lead 5, a first bonding wire 7, a MEMS chip 1, a second VGA amplifier chip 21, a third VGA amplifier chip 27, and a first groove. 4 and the second recess 13 are both located in the first molding body 10, and only the bottom surface pin metal layer 14 is exposed outside the first molding body 10.

First molding body 10, first bonding wire 7, MEMS chip 1, second film 25, second VGA amplifier chip 21, chip bump 22, inner pin upper surface 6, inner pin lower surface 3, The inner lead 5, the third VGA amplifier chip 27, the first UBM 23, the second UBM 26, the bottom surface lead upper surface 6, the first recess 4, the second recess 13, and the bottom lead metal layer 14 constitute the entire circuit. Metal coating by MEMS chip 1, first bonding wire 7, first VGA amplifier chip 8, first UBM 23, chip bump 22, second VGA amplifier chip 21, second UBM 26, inner pin 5, and bottom pin 14 constitutes the power supply and signal channel of the circuit, the output end is firmly contacted, and the high frequency performance is good.

The second VGA amplifier chip 21 and the third VGA amplifier chip 27 are bumped chips.

In the design process of the CSP type MEMS package based on the customized lead frame, the main problems to be solved include how to eliminate the dry deflection, ensure the detection precision of the MEMS chip signal, and reduce the body inductance, bulk capacitance, body resistance of the package and The effects of parasitic inductance, capacitance, resistance, and environmental strain on the signal prevent the output signal from being cut off, distorted, or gained. In addition to the MEMS chip, this package incorporates a wide-band, low-noise, low-distortion, high-gain-precision voltage-controlled VGA amplifier (Variable Gain Amplifire, VGA amplifier) chip with a variable attenuation. The device, the gain control interface and a fixed gain amplifier are three parts, which can automatically adjust the frequency and attenuate and amplify the signal detected by the MEMS device, but without distortion. It is often used in RF automatic gain amplifier, video gain control, A/D. Converter range extension and signal detection system.

Since the package includes at least one MEMS chip and one voltage-controlled VGA chip, the voltage-controlled VGA chip is internally composed of a variable attenuator composed of a seven-stage R-2R ladder network and a fixed gain amplifier, and the attenuation of each stage is 6.02dB, which provides 0~-42.14dB attenuation to the input signal, eliminating the effects of distributed capacitance, inductance, resistance and parasitic capacitance, inductance, and resistance on frequency and signal. An important advantage of this architecture is its superior noise characteristics, with an output signal-to-noise ratio of 86.6dB at 1MHz wideband and a maximum undistorted output of 1Vrms. Moreover, the MEMS chip and the wide-band, low-noise, low-distortion, high-gain precision voltage-controlled VGA amplifier chip are stacked or flip-down, so the package thickness is less than 1mm. It is much smaller than the TO-263 and SOP packages of the same chip.

The manufacturing method of the above MEMS package provided by the present invention is specifically carried out according to the following steps:

Step 1: According to the needs of the chip and the customer, design a multi-row matrix CSP lead frame drawing with different structures and specifications, and make a multi-row (8-16 rows) matrix type carrierless wing-gull type internal lead CSP custom lead frame. The front and back sides of the inner leads are plated with silver or nickel-plated palladium-plated pads, or the UBM metal layer is plated according to the plated flip-chip package. And the back is generally only plated with copper, and the lead frame when grinding is required to be plated with a layer of gold to increase the reliability and wear resistance of the bottom pin contact;

The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

Step 2: For packages without a cover and cavity (as in the first embodiment shown in Figure 1):

On the adhesive sheet bonding machine, the first adhesive sheet 2 is first placed on the front end surface of the lead pin on the lead frame, and then the MEMS chip 1 is reversely placed on the multi-row matrix of the first adhesive sheet 2 The front side of the inner lead of the CSP lead frame is lifted, and all the MEMS chip 1 is baked, and then baked in a section, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and then heated for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 ° minutes to remove the temperature to 70 ° C; the anti-separation process is used in the segment baking process; on the ball welder, the semi-finished multi-row matrix CSP after baking The lead frame is reversely fed, and the second bonding wire 16 is reversed from the back pad 15 of the upturned inner pin of the multi-row matrix CSP lead frame wing gull type to the pad on the MEMS chip 1; On the film sticking machine, the half-packed multi-row matrix CSP lead frame of the second bonding wire 16 is fed, and the second adhesive sheet 9 is marked on the back of the MEMS chip 1, and the first VGA automatically sucked by the device The amplifier chip 8 is accurately placed on the back side of the diced MEMS chip 1, and after bonding the entire first VGA amplifier chip 8 The same stepwise baking is adopted, and the anti-separation layer process is adopted in the segment baking process; on the ball bonding machine, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip 8 is bonded is fed forward. The first bonding wire 7 is driven from the pad on the first VGA amplifier chip 8 to the front pad 11 of the multi-row matrix CSP lead frame wing gull type upturned inner lead; after the bonding wire, the expansion is selected The environmental protection plastic sealing material with coefficient α1≤1, water absorption rate≤0.30%, the punching rate is controlled at 5%, no void and separation layer, post-curing at 150 °C for 5 hours; if the bottom pin is not plated in the frame production Nickel-plated palladium or pure gold, electroplated blunt tin, blunt tin layer thickness 7.62 ~ 15.24μm, and baked at 175 ° C, 1 hour to prevent whisker growth; after laser marking, cutting separation, testing, tape A CSP type MEMS package based on a custom lead frame is prepared; if the bottom surface of the bottom pin is plated with nickel palladium gold or pure gold, no pure tin plating, direct laser marking, shear separation, testing, tape, Making a CSP type MEMS package based on a custom lead frame;

For the package with the cover at the bottom (the second embodiment shown in Figure 2):

On the adhesive sheet bonding machine, the first adhesive sheet 2 is first placed on the front end surface of the lead pin on the lead frame, and then the MEMS chip 1 is reversely placed on the multi-row matrix of the first adhesive sheet 2 The front side of the inner lead of the CSP lead frame is lifted, and all the MEMS chip 1 is baked, and then baked in a section, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and then heated for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 ° minutes to remove the temperature to 70 ° C; the anti-separation process is used in the segment baking process; on the ball welder, the semi-finished multi-row matrix CSP after baking The lead frame is reversely fed, and the second bonding wire 16 is reversed from the back pad 15 of the upturned inner pin of the multi-row matrix CSP lead frame wing gull type to the pad on the MEMS chip 1; On the film sticking machine, the half-packed multi-row matrix CSP lead frame of the second bonding wire 16 is fed, and the second adhesive sheet 9 is marked on the back of the MEMS chip 1, and the first VGA automatically sucked by the device The amplifier chip 8 is accurately placed on the back side of the diced MEMS chip 1, and after bonding the entire first VGA amplifier chip 8 The stepwise baking of the anti-separation layer process is performed; on the ball welder, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip 8 has been bonded is forwardly fed, from the first VGA amplifier chip 8 The pad on the top row of the matrix CSP lead frame wing gull type upturned inner pin of the front pad 11 high and low arc hit first Bonding wire 7; environmentally-friendly transparent plastic sealing material package with expansion coefficient α1≤1, water absorption rate ≤0.25%, CSP semi-finished lead frame after fully automatic encapsulation system and lower cavity transparent plastic sealing mold and MEMS chip bonding wire The punching rate is controlled at 5%, no void and separation layer, and post-curing at 150 ° C for 1 hour; on the adhesive sheeting machine, the post-cured CSP semi-finished lead frame is reversely fed, first in the first A fast curing glue is placed on a groove 4, and the device automatically picks up the MEMS cover plate 17 and places it on the first groove 4 which has been dispensed; then, it is stacked on the back surface of the MEMS chip 1 with an insulating glue or an insulating film. The first voltage-controlled VGA amplifier chip 8 for bonding broadband, low noise, low distortion, and high gain precision is baked at a temperature of 150 ° C to 175 ° C for 3 hours using an anti-off layer process, and then the first VGA amplifier chip 8 is performed. The welding line with low curvature (arc height is controlled at 120μm) on the front side of the upturned pin; after the welding line, the environment-friendly transparent plastic sealing material with expansion coefficient α1 ≤1, water absorption rate ≤0.30% is used, and the automatic encapsulation system and the upper mold are used. Cavity plastic sealing mold for the first VGA amplifier chip 8 after bonding wire C SP semi-finished lead frame is packaged, the punching rate is controlled at 5%, no void and separation layer, and post-cured at 175 ° C for 4 hours; if the bottom surface of the bottom pin is plated with nickel palladium gold or pure gold, then No need to plate pure tin, direct laser marking, cutting and separating, testing, braiding, and making CSP type MEMS package based on custom lead frame; if the bottom surface of the bottom pin is not plated with nickel palladium gold or pure gold, then Pure tin is electroplated on the bottom surface of the bottom pin, and then laser marking, rib separation, testing, braiding, and manufacturing a CSP type MEMS package based on a custom lead frame;

For a package with a cover at the top of the cavity (the third embodiment shown in Figure 3):

The MEMS partition wall 24 is first disposed in parallel on the inner surface 6 of the inner pins 5 of the two rows of oppositely disposed inner pins 5. The two MEMS partition walls 24 and the inner leads 5 form a cavity, that is, a plastic sealing system and a MEMS cavity are used. Mold, using fast curing liquid epoxy molding compound, DOE optimized MEMS cavity process parameters, mold temperature 180 ° C, clamping pressure 90kgf / cm ² , injection pressure 35Kg f / cm ² , injection time 3s, curing time 120s; Then, the MEMS chip with the membrane is pasted in the cavity and subjected to segment baking, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and the temperature is raised to 150 ° C for 5 minutes. Bake for 35 minutes, cool down for 10 minutes and drop the temperature to 70 °C. In the segment baking process, use the anti-separation layer process, wire the wire from the pad on the MEMS chip to the upper surface of the inner pin in the cavity, and then The MEMS cover plate is bonded to the top of the two MEMS partition walls 24 and baked at 150 ° C for 0.5 hours. Then, on the flip-chip bonding machine, the semi-finished lead frame of the bonded cover plate is reverse fed, and the tape is taken. The bumped VGA amplifier chip is flipped on the back of the upturned pin and reflowed It adopts environmentally friendly plastic packaging material with expansion coefficient α1≤1 and water absorption rate≤0.30%. The punching rate is controlled at 5%, no void and separation layer, and post-curing at 175°C for 4 hours; if the bottom surface is on the bottom surface When nickel-palladium gold or pure gold has been plated, it is not necessary to electroplating pure tin, direct laser marking, cutting and separating, testing, braiding, and making a CSP type MEMS package based on a custom lead frame; If there is no electroplated nickel, palladium or pure gold, pure tin is electroplated on the bottom surface of the bottom surface pin, and then laser marking, cutting and separating, testing and braiding are performed to obtain a CSP type MEMS package based on a custom lead frame;

For the package of the MEMS chip on the back side of the upturned pin (the fourth embodiment shown in FIG. 4), the lead frame is reversely fed, and the MEMS chip with the adhesive film is pasted using a film-bonding machine. On the bottom surface of the upturned pin, perform segmental baking, that is, in an oven, heat up for 15 minutes, raise the temperature to 100 ° C for 25 minutes, then heat up for 5 minutes, raise the temperature to 150 ° C for 35 minutes, cool down 10 Minute the temperature to 70 ° C to take out; use the anti-separation process in the segment baking process, from the MEMS chip pad up the back of the pad on the back pad 15 low-radius bonding wire, select the expansion coefficient α1 ≤ 1, water absorption ≤0.25% environmentally-friendly transparent plastic sealing material package, the punching rate is controlled at 5%, no void and separation layer, post-curing at 150 ° C for 0.5 hours; bonding the MEMS cover to the first groove 4, and then On the adhesive film sticking machine, the front side of the semi-finished lead frame of the bonded MEMS cover is fed, and another VGA amplifier chip with the adhesive film is pasted on the front side of the upturned pin, and then subjected to segment baking, that is, In an oven, heat up for 15 minutes, raise the temperature to 100 ° C for 25 minutes, and then heat for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 ° C to remove the temperature to 70 ° C; in the segment baking process using the anti-separation process, the pad on the other VGA amplifier chip up the top of the pad The low-radius welding wire is packaged in an environmentally-friendly molding compound with an expansion coefficient α1 ≤1 and a water absorption rate ≤0.30%, and is post-cured at 175 ° C for 4 hours; if the bottom surface of the bottom pin is plated with nickel-palladium gold or pure gold , instead of electroplating pure tin, direct laser marking, cutting and separating, testing, braiding, and making CSP type MEMS package based on custom lead frame; if the bottom surface of the bottom pin is not Electroplated nickel-palladium gold or pure gold, electroplating pure tin on the bottom surface of the bottom pin, then laser marking, cutting and separating, testing, braiding, and making a CSP-type MEMS package based on a custom lead frame;

For the package of the fifth embodiment shown in FIG. 5, on the flip-chip bonding machine, the lead frame is reversely fed, and the second VGA amplifier chip is reversed on the bottom surface of the upturned pin, that is, the second VGA amplifier. The bump on the chip 21 is connected to the lower surface 3 of the inner lead and is subjected to the first reflow soldering; then, on the flip chip bonding machine, the front side of the semi-finished lead frame to which the second VGA amplifier chip is bonded is fed. The third VGA amplifier chip is reversed on the front side of the upturned pin, that is, the bump on the third VGA amplifier chip 27 is connected to the upper surface 6 of the inner lead, and the second reflow is performed; then, in the film On the sheet bonding machine, the front side of the semi-finished lead frame to which the third VGA amplifier chip is bonded is fed, and the MEMS chip 1 with the adhesive film is stacked on the back side of the third VGA amplifier chip for segment baking, that is, in an oven. After raising the temperature for 15 minutes, the temperature was raised to 100 ° C for 25 minutes, and then the temperature was raised for 5 minutes. The temperature was raised to 150 ° C for 35 minutes, and the temperature was lowered to 70 ° C for 10 minutes; the anti-separation was used during the segmentation baking process. Layer process, positively tilting the pins from the pads on the MEMS chip Low arc welding wire of the pad; the punching rate is controlled at 5%, no void and separation layer, and the environment is packaged with an environmentally-friendly molding compound with expansion coefficient α1≤1 and water absorption rate≤0.30%, and post-cured at 175 °C for 4 hours; If the bottom surface of the bottom surface pin has been plated with nickel-palladium gold or pure gold, then the pure tin is not plated, the laser marking, the rib separation, the test, and the braiding are performed, and the CSP type MEMS package based on the custom lead frame is obtained. If there is no nickel-palladium gold or pure gold on the bottom surface of the bottom pin, pure tin is plated on the bottom surface of the bottom pin, then laser marking, cutting and separating, testing, braiding, and making a custom lead frame based on CSP type MEMS package.

The package generally includes a MEMS chip and a wide-band, low-noise, low-distortion, high-gain precision voltage-controlled VGA amplifier chip. The MEMS chip is back-bonded to the front side of the upturned pin by an insulating glue, and the low-radius line is reversed from the pad of the MEMS chip to the back of the winged gull-shaped inner pin, and the VGA amplifier chip is insulated or insulated. The film is bonded to the back side of the MEMS chip, and the high-low arc welding line is formed from the pad on the VGA amplifier chip to the front surface of the wing-gull type upturned inner pin.

Example 1

According to customer needs, design multi-row matrix CSP lead frame drawings with different structures and specifications, and make 8 rows of matrix-type carrierless wing-gull inner lead CSP custom lead frame. The front and back of the inner lead are except for electroplated copper. It is also silver plated; the wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150 μm, and the wafer without bumps is thinned to 130 μm; The rough grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating; on the adhesive sheeting machine, the lead frame is first tilted. The first adhesive sheet is placed on the front end of the inner lead, and then the MEMS chip is placed in the opposite direction on the front side of the multi-row matrix CSP lead frame of the first adhesive sheet, and all the MEMS chips are stuck. After that, the section baking is carried out, that is, in an oven, the temperature is raised to 100 ° C for 15 minutes. After 25 minutes, the temperature is raised for another 5 minutes, the temperature is raised to 150 ° C for 35 minutes, and the temperature is lowered to 70 ° C for 10 minutes. The anti-separation process is used in the step-by-step baking process. After the semi-finished multi-row matrix CSP lead frame is reverse fed, the back pad of the upturned inner pin of the multi-row matrix CSP lead frame wing gull type is reversed to the lower arc of the MEMS chip. In the film-bonding machine, the semi-finished multi-row matrix CSP lead frame with the second bonding wire is fed, and the second adhesive sheet is drawn on the back of the MEMS chip, and the device automatically picks up the first A VGA amplifier chip is accurately placed on the back side of the diced MEMS chip, and after bonding the first VGA amplifier chip, the same segmented baking is used, and the anti-separation layer process is adopted in the segment baking process; On the welder, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip 8 has been bonded is fed forward, from the pad on the first VGA amplifier chip 8 to the multi-row matrix CSP lead frame wing gull type The top pad of the upturned inner pin 11 is high and low arc to hit the first bond wire 7; After the welding line, the plastic sealing material with expansion coefficient α1≤1, water absorption rate≤0.30% is selected, the punching rate is controlled at 5%, no void and separation layer, and post-curing at 150 °C for 5 hours; bottom introduction The foot is plated with blunt tin, the thickness of the blunt tin layer is 7.62~15.24μm, and it is baked at 175 °C for 1 hour to prevent the growth of tin whiskers; then laser marking and cutting Separating, testing, braiding, and making CSP-type MEMS packages based on custom lead frames.

Example 2

According to the needs of the chip and the customer, design multi-row matrix CSP lead frame drawings with different structures and specifications, and make 16-row matrix carrierless wing-gull inner lead CSP custom lead frame, front and back of the inner lead except plating In addition to copper, nickel-plated palladium-plated pads are also required; wafers are thinned by a 8 吋 to 12 减 thinner, bumped wafers are thinned to 200 μm, and wafers without bumps are thinned to 155μm; rough grinding speed 6μm/s during the thinning process, refining speed 0.15μm/s, polishing speed 0.05μm/s; at the same time adopting anti-warping process: then, using A-WD-300TXB dicing machine to thin The wafer is diced, and the dicing process is performed by a double-knife process for preventing chipping. The dicing feed speed is ≤10 mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating; On the machine, first place the first adhesive on the front end of the lead on the lead frame, and then place the MEMS chip in the opposite direction on the multi-row matrix CSP lead frame of the first adhesive. On the front side, after all the MEMS chips are glued, they are subjected to segment baking, that is, in the oven, the temperature rises 15 In the minute, the temperature is raised to 100 ° C for 25 minutes, and then heated for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 minutes to remove the temperature to 70 ° C; the anti-separation process is used in the segment baking process; On the ball welder, the baked semi-finished multi-row matrix CSP lead frame is reverse fed, from the back pad of the multi-row matrix CSP lead frame wing gull type upturned inner pin to the MEMS chip The pad is reversed to the second arc of the lower arc; on the film sticking machine, the semi-assembled multi-row matrix CSP lead frame of the second bonding wire is fed, and the second side of the MEMS chip is marked. Adhesive glue, the first VGA amplifier chip automatically picked up by the device, accurately placed on the back side of the MEMS chip that has been glued, after bonding the first VGA amplifier chip, using the same segmental baking, in the segment baking The anti-separation layer process is adopted in the process; on the ball welder, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip is bonded is forwardly fed, from the pad on the first VGA amplifier chip to the multi-row Matrix CSP lead frame wing gull type upturned inner lead front pad The first bonding wire is used in low arc; the environmentally-friendly transparent plastic sealing material package with expansion coefficient α1≤1 and water absorption rate≤0.25% is used, and the automatic encapsulation system and the lower cavity transparent plastic sealing mold and the MEMS chip bonding wire are used. CSP semi-finished lead frame, the punching rate is controlled at 5%, no void and separation layer, and post-curing at 150 ° C for 1 hour; on the adhesive sheeting machine, the post-cured CSP semi-finished lead frame is reversely fed First, the fast curing glue is spotted on the first groove, and the device automatically picks up the MEMS cover plate and places it on the first groove of the glue; then stacks the back surface of the MEMS chip with an insulating glue or an insulating film. Bonding a wide-band, low-noise, low-distortion, high-gain precision first voltage-controlled VGA amplifier chip, baked at a temperature of 150 ° C ~ 175 ° C using a separation layer process for 3 hours, and then the first VGA amplifier chip and The arc of the front side of the tilting pin is low arc (the arc height is controlled at 120μm); after the wire is welded, the environmentally-friendly transparent plastic sealing material with the expansion coefficient α1≤1 and the water absorption rate ≤0.30% is used, and the automatic encapsulation system and the upper cavity cavity plastic seal are used. Mold to the first VGA amplifier chip After-line CSP semi-finished lead frame is packaged, the punching rate is controlled at 5%, no void and separation layer, and post-cured at 175 °C for 4 hours; laser marking, cutting separation, testing, braiding, based on Customized lead frame CSP type MEMS package.

Example 3

According to the needs of the chip and the customer, design multi-row matrix CSP lead frame drawings with different structures and specifications, and make 12-row matrix carrierless wing-gull type internal lead CSP custom lead frame, front and back of the inner lead except plating In addition to copper, the UBM metal layer required for flip-chip packaging is also required; the wafer is thinned by a 8 吋 to 12 减 thinner, and the bumped wafer is thinned to 175 μm, without bumps. Thinning to 180μm; rough grinding speed of 6μm/s during the thinning process, refining speed of 0.15μm/s, polishing speed of 0.05μm/s; and anti-warping process: then, using A-WD-300TXB dicing machine The diced wafer is diced, and the dicing process is performed by a double-knife process for preventing sharding. The dicing feed speed is ≤10 mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating; MEMS partition walls are arranged in parallel on the upper surface of the inner pins of the oppositely disposed inner pins, and the two MEMS partition walls and inner leads form a cavity, that is, using a plastic sealing system and a MEMS cavity mold, using a fast curing liquid epoxy Molding material, MEMS cavity process parameters are optimized by DOE, mold temperature 1 80°C, clamping pressure 90kgf/cm ² , injection pressure 35Kg f/cm ² , injection time 3s, curing time 120s; then, the MEMS chip with diaphragm is stuck in the cavity for segment baking, ie in the oven In the temperature rise for 15 minutes, the temperature is raised to 100 ° C for 25 minutes, and then the temperature is raised for 5 minutes, the temperature is raised to 150 ° C for 35 minutes, the temperature is lowered for 10 minutes, the temperature is lowered to 70 ° C to take out; The separation process, from the pad on the MEMS chip to the inner surface of the inner lead in the cavity, and then bonding the MEMS cover on the top of the two MEMS partitions, baking at 150 ° C for 0.5 hours; On the flip-chip bonding machine, the semi-finished lead frame of the bonded cover plate is reversely fed, and the bumped VGA amplifier chip is buckled on the back side of the upturned pin and reflowed; the expansion coefficient α1≤ is selected. 1. The environmental protection plastic packaging material with water absorption rate ≤0.30%, the punching rate is controlled at 5%, no void and separation layer, and post-curing at 175 °C for 4 hours; if there is no electroplated nickel-palladium on the bottom surface of the bottom pin, Plating pure tin on the bottom surface of the bottom pin, then laser marking and cutting Separating, testing, taping, obtained based on customized leadframe CSP type MEMS package.

Example 4

According to the chip and customer needs, design multi-row matrix CSP lead frame drawings with different structures and specifications, make 10 rows of matrix carrierless wing gull type internal lead CSP custom lead frame, front and back of the inner lead except plating In addition to copper, the UBM metal layer required for flip-chip packaging is also required; the wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 160 μm, and the bumpless wafer Thinning to 140μm; rough grinding speed of 6μm/s during thinning, fine grinding speed of 0.15μm/s, polishing speed of 0.05μm/s; simultaneous anti-warping process: then, using A-WD-300TXB dicing machine The diced wafer is diced, and the dicing process is performed by a double-knife process for preventing sharding. The dicing feed speed is ≤10 mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating; the lead frame is reversed. To feed, the MEMS chip with the adhesive film is pasted on the bottom surface of the upturned pin by means of a rubber film sticking machine, and is subjected to segment baking, that is, in an oven, the temperature is raised to 100 ° C for 15 minutes. Bake for 25 minutes, heat for another 5 minutes, raise the temperature to 150 ° C for 35 minutes, cool down 10 Minutes the temperature to 70 ° C to take out; in the segment baking process using the anti-separation layer process, from the MEMS chip pad up the back of the pad on the back pad low arc welding wire, the choice of expansion coefficient α1 ≤ 1, water absorption rate ≤ 0.25% environmentally-friendly transparent plastic sealing material package, the punching rate is controlled at 5%, no void and separation layer, post-curing at 150 °C for 0.5 hour; the MEMS cover is bonded to the first groove, then, in the glue On the film sticking machine, the front side of the semi-finished lead frame of the bonded MEMS cover is fed, and another VGA amplifier chip with the adhesive film is pasted on the front side of the upturned pin, and then the same segment baking is performed. In the segment baking process, the anti-separation layer process is adopted, and the low-radiation bonding wire of the front pad of the upturned pin from the pad on the other VGA amplifier chip is packaged in an environmentally-friendly plastic package with an expansion coefficient α1≤1 and a water absorption rate≤0.30%. After curing at 175 ° C for 4 hours; the bottom surface of the bottom pin is not plated with pure gold, then pure tin is plated on the bottom surface of the bottom pin, then laser marking, cutting and separating, testing, braiding, and CSP type MEMS package based on custom lead frame .

Example 5

According to the needs of the chip and the customer, design multi-row matrix CSP lead frame drawings with different structures and specifications, and make 14 rows of matrix-type carrierless wing-gull inner lead CSP custom lead frame, front and back of the inner lead except plating In addition to copper, the UBM metal layer required for flip-chip packaging is also required; the wafer is thinned by a 8 吋 to 12 减 thinner, and the bumped wafer is thinned to 180 μm, without bumps. Thinning to 170μm; rough grinding speed of 6μm/s during the thinning process, refining speed of 0.15μm/s, polishing speed of 0.05μm/s; and anti-warping process: then, using A-WD-300TXB dicing machine Dividing the thinned wafer, using the anti-fragment double-knife process dicing during the dicing process, the dicing feed speed is ≤10mm/s, cutting and separating to form the required MEMS IC chip and VGA amplifier chip; On the bonding machine, the lead frame is reversely fed, and the second VGA amplifier chip is reversed on the bottom surface of the upturned pin, that is, the bump on the second VGA amplifier chip is connected to the lower surface of the inner pin, and is first Secondary reflow soldering; then, on the flip-chip bonding machine, the second VGA will be bonded The semi-finished lead frame of the large chip is fed in front, and the third VGA amplifier chip is reversed on the front side of the upturned pin, that is, the bump on the third VGA amplifier chip is connected to the upper surface of the inner pin, and the second is performed. Sub-reflow soldering; then, on the film-bonding machine, the front side of the semi-finished lead frame to which the third VGA amplifier chip is bonded is fed, and the MEMS chip with the adhesive film is stacked on the back side of the third VGA amplifier chip for division Segment baking, that is, in an oven, the temperature is raised to 100 ° C for 15 minutes, and the temperature is raised to 150 ° C for 35 minutes. After cooling for 10 minutes, the temperature is lowered to 70 ° C. The anti-separation process is used in the segment baking process, and the pad on the front surface of the MEMS chip is tilted up to the lower arc of the lead wire; the punch rate is controlled at 5%. No voids and separation layer, packaged with environmentally friendly plastic sealing material with expansion coefficient α1≤1, water absorption rate≤0.30%, post-curing at 175°C for 4 hours; no nickel-palladium plating on the bottom surface of the bottom surface pin, bottom surface Pure tin is electroplated on the bottom surface of the pin, and then laser marking, rib separation, testing, and tape-making are performed to produce a CSP type MEMS package based on a custom lead frame.

While the invention has been shown and described with reference to the preferred embodiments embodiments

Claims (9)

1. A CSP type MEMS package based on a custom lead frame, characterized in that it comprises a lead frame, the inner pin (5) in the lead frame is connected to the bottom surface pin (12), and the inner pin upper surface (6) is flipped There is a bumped MEMS chip (1), and the bump on the MEMS chip (1) is connected to the back pad (15) of the inner lead through the second bonding wire (16); the MEMS chip (1) is pasted thereon a first VGA amplifier chip (8), the first VGA amplifier chip (8) is connected to the upper surface (6) of the inner pin through the first bonding wire (7); and is connected to the pin (12) perpendicular to the bottom surface of the two rows The first groove (4) and the second groove (13) are disposed in parallel with the direction of the bottom surface pin (12) away from the inner surface of the upper surface (6) of the inner pin, and the bottom surface of the bottom pin (12) The bottom lead metal layer (14) is provided; the lead frame is molded with a first molding body (10), and all the devices are molded in the first molding body (10), and only the bottom surface pin metal layer (14) is exposed first. Outside the plastic body (10).
2. The custom lead frame-based CSP type MEMS package according to claim 1, wherein a MEMS cover plate (17) and a MEMS cover plate (17) are disposed between the two rows of bottom surface pins (12). One side is fixed to the first recess (4) on a row of bottom surface pins (12), and the MEMS cover (17) is provided with a MEMS cover opening (19); the MEMS cover (17), the inner A second plastic body (18) is molded in the cavity surrounded by the pin (5) and the MEMS chip (1).
3. A CSP type MEMS package based on a custom lead frame, comprising a lead frame, wherein an inner pin (5) in the lead frame is connected to a bottom surface pin (12), and an inner pin upper surface (6) is pasted There is a MEMS chip (1), the MEMS chip (1) is connected to the upper surface (6) of the inner pin through the first bonding wire (7), and the MEMS partition wall (24) is provided on the upper surface (6) of the inner pin, two The top of the MEMS partition wall (24) is connected by a MEMS cover plate (17), and the MEMS cover plate (17) is provided with a MEMS cover opening (19), a MEMS partition wall (24), a MEMS cover plate (17), The inner pin upper surface (6) and the MEMS chip (1) enclose a cavity in which a second molding body (18) is molded, and the first bonding wire (7) is located in the second molding body (18). The inner pin lower surface (3) is bonded to the second VGA amplifier chip (21) through the first UBM (23), and the chip bumps on the first UBM (23) and the second VGA amplifier chip (21) (22) The phase is bonded; the first groove (4) is disposed in parallel with the direction perpendicular to the line connecting the bottom row pins (12) of the two rows, and the bottom surface pin (12) is parallel to the sides of the upper surface (6) of the inner lead. And a second recess (13), the bottom surface of the bottom surface pin (12) is provided with a bottom pin metal layer (14); on the lead frame The first molding body (10) is molded, except for the cavity, the MEMS cover plate 17) and the bottom pin metal layer (14), and all the other devices are molded in the first molding body (10).
4. A CSP type MEMS package based on a custom lead frame, characterized in that it comprises a lead frame, the inner pin (5) in the lead frame is connected to the bottom surface pin (12), and the MEMS chip (1) is attached to the inner lead On the lower surface (3), the MEMS chip (1) is connected to the lower surface (3) of the inner pin through the second bonding wire (16); the first VGA amplifier chip is pasted on the upper surface (6) of the inner pin ( 8), the first VGA amplifier chip (8) is connected to the upper surface (6) of the inner pin through the first bonding wire (7); the direction and the bottom surface pin are perpendicular to the line connecting the pins (12) of the bottom row of the two rows (12) A first groove (4) and a second groove (13) are disposed in parallel on both sides of one end of the upper surface (6) of the inner lead, and the bottom surface of the bottom pin (12) is provided with a bottom metal a layer (14); the lead frame is molded with a first molding body (10), except for the cavity, the MEMS cover plate 17) and the bottom pin metal layer (14), all the other devices are molded on the first molding body ( 10) inside; two rows of bottom surface pins (12) are provided with a MEMS cover plate (17), one side of the MEMS cover plate (17) and a row of bottom surface pins (12) on the first groove (4) Fixed, MEMS cover (17) is provided with MEMS cover opening (19); MEMS cover (17) The pin (5) and the MEMS chip (1) a cavity surrounded by the second plastic molding material (18).
5. A CSP type MEMS package based on a custom lead frame, characterized in that it comprises a lead frame using a plurality of rows of matrix CSP nickel-palladium gold electroplated frames, wherein the inner leads (5) are tilted upward to form a gull wing The third VGA amplifier chip (27) is mounted on the upper surface (6) of the inner pin, and the MEMS chip (1) is bonded to the upper surface of the third VGA amplifier chip (27), and the MEMS chip (1) passes the first The bonding wire (7) is connected to the upper surface (6) of the inner pin; the second VGA amplifier chip (21) is mounted on the lower surface (3) of the inner pin; and the pin (12) is perpendicular to the bottom of the two rows. The direction of the line and the bottom surface pin (12) are disposed away from the two sides of the upper surface of the inner lead (6) in parallel with the first recess (4) and the second recess (13), and the bottom surface of the bottom pin (12) There is a bottom pin metal layer (14); the lead frame is molded with The first molding body (10), the bottom pin metal layer (14) exposes the first molding body (10), and all other components are located in the first molding body (10).
6. A method for manufacturing a custom lead frame-based CSP type MEMS package according to claim 1, wherein the method is specifically as follows:

   Step 1: Make a multi-row matrix carrierless wing gull-type internal CSP lead frame with the front and back sides of the inner leads in addition to electroplated copper, silver or nickel-plated palladium-plated pads, or flip-chip according to plating The package needs to be plated with a UBM metal layer;

   The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

   Step 2: On the adhesive sheet bonding machine, first place the first adhesive sheet on the front end surface of the lead pin on the lead frame, and then place the MEMS chip in reverse on the multi-row matrix of the first adhesive sheet. The front side of the inner lead of the CSP lead frame is lifted, and all the MEMS chip 1 is baked, and then baked in a section, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and then heated for 5 minutes. The temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 ° minutes to remove the temperature to 70 ° C; the anti-separation process is used in the segment baking process; on the ball welder, the semi-finished multi-row matrix CSP after baking The lead frame is reversely fed, and the back pad of the upturned inner pin of the multi-row matrix CSP lead frame wing gull type is reversed to the second radiant wire of the pad on the MEMS chip; the film is stuck in the film On the chip machine, the semi-assembled multi-row matrix CSP lead frame with the second bonding wire is fed, and the second adhesive sheet is drawn on the back of the MEMS chip, and the first VGA amplifier chip automatically picked up by the device is accurately placed in the film. The back side of the MEMS chip that has been glued, after bonding the first VGA amplifier chip The same as the segmented baking, the anti-separation process is used in the segment baking process; on the ball welder, the semi-finished multi-row matrix CSP lead frame to which the first VGA amplifier chip is bonded is fed forward, from the first The pad on a VGA amplifier chip is applied to the front pad of the multi-row matrix CSP lead frame wing gull type upturned inner pin, and the first bonding wire is used; after the bonding wire, the expansion coefficient α1 ≤ 1, Plastic packaging material with water absorption rate ≤0.30%, the punching rate is controlled at 5%, no void and separation layer, post-curing at 150 °C for 5 hours; if the bottom pin is not plated with nickel-plated palladium in frame production or Pure gold, electroplated blunt tin, blunt tin layer thickness 7.62 ~ 15.24μm, and baked at 175 ° C, 1 hour to prevent tin whisker growth; after laser marking, cutting rib separation, testing, braiding, based on custom CSP type MEMS package of lead frame; if nickel, palladium gold or pure gold is plated on the bottom surface of the bottom pin, no pure tin plating, direct laser marking, separation of ribs, testing, braiding, and manufacturing based on custom leads Framed CSP type MEMS package.
7. A method for manufacturing a custom lead frame-based CSP type MEMS package according to claim 3, characterized in that the following steps are specifically performed:

   Step 1: Make a multi-row matrix carrierless wing gull-type internal CSP lead frame with the front and back sides of the inner leads in addition to electroplated copper, silver or nickel-plated palladium-plated pads, or flip-chip according to plating The package needs to be plated with a UBM metal layer;

   The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

   Step 2: First, MEMS partition walls are arranged in parallel on the upper surface of the inner pins of the two rows of oppositely disposed inner pins, and the two MEMS partition walls and the inner leads form a cavity; then, the MEMS chip with the diaphragm is pasted In the cavity, the section baking is carried out, that is, in the oven, the temperature is raised to 100 ° C for 15 minutes, the temperature is raised to 5 ° C for 25 minutes, the temperature is raised to 150 ° C for 35 minutes, and the temperature is lowered by 10 minutes. Take out to 70 ° C; use the anti-separation process in the segment baking process, from the pad on the MEMS chip to the inner surface of the inner lead in the cavity, and then bond the MEMS cover on the top of the two MEMS partitions. , baking at 150 ° C for 0.5 hours; then on the flip-chip machine, the half of the bonded cover The lead frame of the product adopts a reverse feeding mode, and the bumped VGA amplifier chip is buckled on the back side of the upturned pin and reflowed; the environmentally friendly plastic sealing material with the expansion coefficient α1≤1 and the water absorption rate≤0.30% is selected. The punching rate is controlled at 5%, void-free and separated, and post-cured at 175 °C for 4 hours. If the bottom surface of the bottom pin is plated with nickel-palladium gold or pure gold, then no pure tin plating, direct laser Marking, cutting, separating, testing, tape-making, making CSP-type MEMS package based on custom lead frame; if the bottom surface of the bottom pin is not plated with nickel-palladium gold or pure gold, plating on the bottom surface of the bottom pin Pure tin, then laser marking, cutting and separating, testing, braiding, and making CSP-type MEMS packages based on custom lead frames.
8. A method for manufacturing a custom lead frame-based CSP type MEMS package according to claim 4, wherein the method is specifically as follows:

   Step 1: Make a multi-row matrix carrierless wing gull-type internal CSP lead frame with the front and back sides of the inner leads in addition to electroplated copper, silver or nickel-plated palladium-plated pads, or flip-chip according to plating The package needs to be plated with a UBM metal layer;

   The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

   Step 2: Reverse feeding of the lead frame, using a film-bonding machine, pasting the MEMS chip with the adhesive film on the bottom surface of the upturned pin for segmental baking, that is, heating in the oven for 15 minutes The temperature is raised to 100 ° C for 25 minutes, the temperature is raised for 5 minutes, the temperature is raised to 150 ° C for 35 minutes, the temperature is lowered to 10 minutes to remove the temperature to 70 ° C; the segmentation baking process uses the anti-separation process, from the MEMS The low-radius bonding wire on the back pad of the pad on the chip is used for the low-radius bonding wire with the expansion coefficient α1≤1 and the water absorption rate ≤0.25%. The punching rate is controlled at 5%, no void and separation layer. After curing at 150 ° C for 0.5 hour; bonding the MEMS cover to the first groove, and then feeding the front surface of the semi-finished lead frame of the bonded MEMS cover on the film-bonding machine, the other A VGA amplifier chip with a film is attached to the front side of the upturned pin, and then baked in sections, that is, in an oven, the temperature is raised to 100 ° C for 25 minutes, and the temperature is raised by 5 minutes. Bake at 150 ° C for 35 minutes, cool down for 10 minutes and remove the temperature to 70 ° C; In the segment baking process, the anti-separation layer process is adopted, and the low-radiation bonding wire of the front pad of the upturned pin from the pad on the other VGA amplifier chip is packaged in an environmentally-friendly plastic package with an expansion coefficient α1≤1 and a water absorption rate≤0.30%. After curing at 175 ° C for 4 hours; if the bottom surface of the bottom pin has been plated with nickel palladium gold or pure gold, then no plating of pure tin, direct laser marking, cutting separation, testing, braiding, system CSP type MEMS package based on custom lead frame; if there is no nickel-palladium gold or pure gold on the bottom surface of the bottom pin, pure tin is plated on the bottom surface of the bottom pin, then laser marking, cutting separation, testing , tape, and make CSP type MEMS package based on custom lead frame.
9. A method for manufacturing a custom lead frame-based CSP type MEMS package according to claim 5, wherein the method is specifically as follows:

   Step 1: Make a multi-row matrix carrierless wing gull-type internal CSP lead frame with the front and back sides of the inner leads in addition to electroplated copper, silver or nickel-plated palladium-plated pads, or flip-chip according to plating The package needs to be plated with a UBM metal layer;

   The wafer is thinned by a 8 吋 to 12 减 thinner, the bumped wafer is thinned to 150-200 μm, and the wafer without bumps is thinned to 130-180 μm; the thinning process is thick The grinding speed is 6μm/s, the finishing speed is 0.15μm/s, and the polishing speed is 0.05μm/s. At the same time, the anti-warping process is adopted: Then, the thinned wafer is diced and drawn by A-WD-300TXB dicing machine. In the process of film, the anti-fragment double-knife process dicing is adopted, and the dicing feed speed is ≤10mm/s, and the MEMS IC chip and the VGA amplifier chip are formed by cutting and separating;

   Step 2: On the flip-chip bonding machine, the lead frame is reversely fed, and the second VGA amplifier chip is reversed on the bottom surface of the upturned pin, that is, the bump on the second VGA amplifier chip is opposite to the lower surface of the inner pin. Connecting and performing the first reflow soldering; then, on the flip chip bonding machine, the front side of the semi-finished lead frame to which the second VGA amplifier chip is bonded is fed, and the third VGA amplifier chip is reversed on the upturned pin The front side, that is, the bump on the third VGA amplifier chip and the internal pin on the table The surface is connected and subjected to a second reflow soldering; then, on the film bonding machine, the front side of the semi-finished lead frame to which the third VGA amplifier chip is bonded is fed, and the MEMS chip with the adhesive film is stacked in the third The back side of the VGA amplifier chip is baked in sections, that is, in an oven, the temperature is raised to 100 ° C for 15 minutes, and the temperature is raised to 150 ° C for 35 minutes, and the temperature is raised to 150 ° C for 35 minutes. Take out to 70 ° C to take out; use the anti-separation layer process in the segment baking process, from the pad on the MEMS chip up the pad on the front side of the pad low arc bonding wire; the line rate is controlled at 5%, no voids and away The layer is made of environmentally-friendly molding compound with expansion coefficient α1≤1 and water absorption rate≤0.30%, and is post-cured at 175°C for 4 hours. If the bottom surface of the bottom surface has been plated with nickel-palladium gold or pure gold, then it is not used. Electroplating pure tin, direct laser marking, cutting and separating, testing, braiding, and making CSP type MEMS package based on custom lead frame; if the bottom surface of the bottom pin is not plated with nickel palladium gold or pure gold, then the bottom surface Plating pure tin on the underside of the pin, then Marking light, cut tendons separation, testing, taping, obtained based on customized leadframe CSP type MEMS package.

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