MEMS sensor packaging structure

Abstract

An MEMS sensor packaging structure comprises a first chip and a second chip, and the second chip is stacked on the first chip; the plurality of bonding pads are arranged on the first chip and the second chip, the plurality of bonding pads comprise corresponding auxiliary bonding pads and first functional bonding pads, the auxiliary bonding pads are connected with one end of an auxiliary bonding wire, the other end of the auxiliary bonding wire is open-circuited or coupled with a grounding end, the first functional bonding pads are connected with a first functional bonding wire, and the first functional bonding wire is connected with a second functional bonding wire. The other ends of the first function key leads are in contact with the metal wiring layer, and the auxiliary bonding leads are in one-to-one correspondence with the first function key leads. According to the MEMS sensor packaging structure, the space can be saved, and the degree of freedom of an electric connection mode between the MEMS sensor chip and the corresponding ASIC chip is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to sensor integration technical field especially relates to a MEMS sensor packaging structure. BACKGROUND

[0002] Devices manufactured based on micro-electro-mechanical system (MEMS) are referred to as MEMS devices, and using MEMS devices as sensors is one of the application directions. A MEMS sensor generally comprises a MEMS sensor chip and a corresponding application specific integrated circuit (ASIC), wherein the MEMS sensor chip is designed as a sensing structure for generating an electrical quantity in response to a detected quantity (for example: acceleration, angular velocity or pressure, etc.), and the ASIC chip integrates corresponding circuit elements and is coupled with the MEMS to process (for example: amplify and filter) the electrical quantity generated by the sensing structure and supply an output signal (for example: a voltage indicating the detected quantity).

[0003] In the prior art, a conversion board is provided, and the MEMS sensor chip and the corresponding ASIC chip are connected to the conversion board by means of wire bondings, etc. to realize the coupling between the MEMS sensor chip and the corresponding ASIC chip. However, this method results in a large space occupied by the packaging structure of the MEMS sensor, and the electrical connection mode between the MEMS sensor chip and the corresponding ASIC chip is relatively single. SUMMARY

[0004] The technical problem solved by the utility model is to provide a MEMS sensor packaging structure to save the space occupied by the packaging structure of the MEMS sensor and improve the degree of freedom of the electrical connection mode between the MEMS sensor chip and the corresponding ASIC chip.

[0005] To solve the above technical problem, the technical scheme of the utility model provides a MEMS sensor packaging structure comprising: a first chip and a second chip, wherein the second chip is stacked on the first chip; a plurality of pads arranged on the first chip and the second chip, and the plurality of pads comprise corresponding auxiliary pads and first functional pads, one end of the auxiliary pad is connected to an auxiliary wire bonding, the other end of the auxiliary wire bonding is open or coupled with a ground terminal, the first functional pad is connected to a first functional wire bonding, the other end of the first functional wire bonding is in contact with a metal wiring layer, and the auxiliary wire bonding and the first functional wire bonding correspond to each other.

[0006] Optionally, the surface of the first chip is provided with a plastic sealing layer, and the plastic sealing layer covers the second chip, the plurality of pads, the auxiliary bonding wire and the first functional bonding wire are located in the plastic sealing layer, and the surface of the plastic sealing layer exposes the other end of the auxiliary bonding wire and the other end of the first functional bonding wire.

[0007] Optionally, the corresponding auxiliary bonding wire is adjacent to the first functional bonding wire and is inclined towards the first functional bonding wire.

[0008] Optionally, the plurality of pads further include a corresponding second functional pad and a third functional pad, the second functional pad is arranged on the first chip, the third functional pad is arranged on the second chip, and the two ends of a second functional bonding wire are respectively connected to the corresponding second functional pad and the third functional pad, and the second functional bonding wire is covered by the plastic sealing layer.

[0009] Optionally, the surface of the plastic sealing layer is provided with an insulating layer, and the insulating layer covers the other end of the auxiliary bonding wire.

[0010] Optionally, the metal wiring layer is arranged on the surface of the plastic sealing layer and located in the insulating layer, and the other end of the first functional bonding wire is in contact with the bottom surface of the metal wiring layer.

[0011] Optionally, the insulating layer includes a first insulating layer and a second insulating layer, the first insulating layer is located on the surface of the plastic sealing layer, the metal wiring layer is also located on the surface of the first insulating layer, the second insulating layer is located on the surfaces of the first insulating layer and the metal wiring layer, a plurality of solder balls are further arranged above the insulating layer, and a solder ball lower metallization layer is connected between the solder balls and the metal wiring layer.

[0012] Optionally, the plurality of pads further include a corresponding fourth functional pad and a fifth functional pad, the fourth functional pad is arranged on the first chip, the fifth functional pad is arranged on the second chip, the fourth functional pad is connected to one end of a third functional bonding wire, the fifth functional pad is connected to one end of a fourth functional bonding wire, the other end of the third functional bonding wire and the other end of the fourth functional bonding wire are in contact with the metal wiring layer, and the third functional bonding wire and the fourth functional bonding wire are electrically interconnected based on the metal wiring layer.

[0013] Optionally, each pad arranged on the first chip surrounds the second chip, and the two pads having a corresponding relationship are adjacent to each other in the two orthographic projections on the surface of the first chip.

[0014] Optionally, the first chip is an ASIC chip, the second chip is a MEMS sensor chip, and the first chip is bonded to the second chip.

[0015] Compared with the prior art, the technical scheme of the utility model has the following beneficial effects:

[0016] In the MEMS sensor packaging structure provided by the technical scheme, the plurality of pads include the corresponding auxiliary pads and the first function pads, that is, each pad in the plurality of pads corresponds to at least one remaining pad by arranging the auxiliary pads in the plurality of pads, so that the formation of the bonding wires on all pads of the first chip and all pads of the second chip can be directly completed when the chip-level packaging of the first chip and the second chip is performed, and the bonding wires connected between the auxiliary pads and the first function pads can be disconnected through a grinding process or the like. On this basis, since one end of the auxiliary bonding wire is connected to the auxiliary pad, and the other end of the auxiliary bonding wire is open or coupled to the ground terminal, the auxiliary pad is insulated or grounded. At the same time, since the first function pad is connected to the first function bonding wire, and the other end of the first function bonding wire is in contact with the metal wiring layer, the various electrical connection requirements of the first function pad (for example, electrical connection with other pads through the metal wiring layer, external lead through the metal wiring layer, etc.) can be met. In summary, the MEMS sensor packaging structure occupies a small space, not only can the formation of the bonding wires connected to all pads be completed in the chip-level packaging process, but also takes into account the high degree of freedom of the electrical connection mode of the first chip and the second chip. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a top view structural schematic diagram of the MEMS sensor packaging structure of the utility model embodiment one;

[0018] Figure 2 is Figure 1 a cross-sectional structural schematic diagram along A1-A2 in the

[0019] Figure 3 is a top view structural schematic diagram of the MEMS sensor packaging structure of the utility model embodiment two;

[0020] Figure 4 is Figure 3 a cross-sectional structural schematic diagram along B1-B2 in the

[0021] Figure 5 is a top view structural schematic diagram of the MEMS sensor packaging structure of the utility model embodiment three;

[0022] Figure 6 is Figure 5 a cross-sectional structural schematic diagram along C1-C2 in the

[0023] Figure 7 is a top view structural schematic diagram of the MEMS sensor packaging structure of the fourth embodiment of the present application;

[0024] Figure 8 is Figure 7 is a cross-sectional structural schematic diagram along D1-D2 in the middle of the MEMS sensor packaging structure;

[0025] Figures 9 to 20 is a process schematic diagram of each step of the forming method of the MEMS sensor packaging structure of an embodiment of the present application.

[0026] Reference signs:

[0027] 11-first wafer; 10-first chip; 20-second chip;

[0028] 100-pad; 101, 102-assistant pad; 111, 112-first functional pad; 120-second functional pad;

[0029] 130-third functional pad; 140-fourth functional pad; 150-fifth functional pad;

[0030] 200-initial bonding lead; 201, 202-assistant bonding lead; 211, 212-first functional bonding lead;

[0031] 220-second functional bonding lead; 230-third functional bonding lead; 240-fourth functional bonding lead;

[0032] 301-initial plastic sealing layer; 300-plastic sealing layer;

[0033] 400-metal wiring layer;

[0034] 500-insulating layer; 510-first insulating layer; 520-second insulating layer; 511, 521-opening;

[0035] 610-soldering ball; 620-soldering ball lower metallization layer;

[0036] 700-glue layer. DETAILED DESCRIPTION

[0037] As described in the background, the existing packaging structure of the MEMS sensor occupies a large space, and the electrical connection mode between the MEMS sensor chip and the corresponding ASIC chip is also relatively single.

[0038] The technical scheme of the utility model provides a packaging structure of MEMS sensor, through setting up auxiliary soldering pad, and making one end of auxiliary soldering pad connect auxiliary bonding lead, the other end of auxiliary bonding lead is open circuit or is coupled with ground terminal, make MEMS sensor packaging structure realize the space occupied is small, can complete the formation of bonding lead connected with all soldering pads in the chip level packaging process, and give consideration to the high degree of freedom electrical connection mode of first chip and second chip.

[0039] In order to make the above-mentioned purpose, features and beneficial effects of the utility model more obvious and easy to understand, the specific embodiments of the utility model will be described in detail below with reference to the drawings.

[0040] Embodiment one

[0041] Please refer to Figure 1 And Figure 2 The packaging structure of MEMS sensor includes: first chip 10, second chip 20, a plurality of soldering pads 100 and metal wiring layer 400.

[0042] Second chip 20 is stacked on first chip 10.

[0043] In some embodiments, first chip 10 is ASIC chip, second chip 20 is MEMS sensor chip, and first chip 10 is bonded with second chip 20.

[0044] Specifically, second chip 20 is attached to first chip 10 through adhesive layer 700.

[0045] A plurality of soldering pads 100 are arranged on first chip 10 and second chip 20, and a plurality of soldering pads 100 include corresponding auxiliary soldering pad 101 and first functional soldering pad 112. That is to say, auxiliary soldering pad 101 and first functional soldering pad 112 are both specific soldering pad 100 in a plurality of soldering pads 100.

[0046] In the embodiment, auxiliary soldering pad 101 is arranged on first chip 10, first functional soldering pad 112 is arranged on second chip 20, and the number of auxiliary soldering pad 101 is more than one, and the number of first functional soldering pad 112 is more than one. That is to say, the number of auxiliary soldering pad 101 can be one, two or more.

[0047] For the convenience of description, Figure 1 One auxiliary soldering pad 101 is schematically represented in the figure.

[0048] In addition, the corresponding relationship between auxiliary soldering pad 101 and first functional soldering pad 112 can be as Figure 1The one-to-one correspondence can also be that one auxiliary pad 101 corresponds to two or more first function pads 112, or that one first function pad 112 corresponds to two or more auxiliary pads 101.

[0049] The auxiliary pad 101 is connected to one end of the auxiliary bonding wire 201, and the other end of the auxiliary bonding wire 201 is open.

[0050] In some embodiments, the other end of the auxiliary bonding wire 201 is coupled to a ground terminal.

[0051] The first function pad 112 is connected to the first function bonding wire 212, and the other end of the first function bonding wire 212 is in contact with the metal wiring layer 400.

[0052] The auxiliary bonding wire 201 and the first function bonding wire 212 are in one-to-one correspondence.

[0053] Since the plurality of pads 100 include the corresponding auxiliary pad 101 and the first function pad 112, that is, by providing the auxiliary pad 101 in the plurality of pads 100, each pad 100 in the plurality of pads 100 corresponds to at least one remaining pad 100, when the chip-level packaging of the first chip 10 and the second chip 20 is performed, the formation of the bonding wire can be directly completed on all pads 100 of the first chip 10 and all pads 100 of the second chip 20, and the bonding wire connected between the auxiliary pad 101 and the first function pad 112 can be disconnected by a grinding process or the like. On this basis, since the auxiliary pad 101 is connected to one end of the auxiliary bonding wire 201, and the other end of the auxiliary bonding wire 201 is open or coupled to a ground terminal, the auxiliary pad 101 is insulated or grounded. At the same time, since the first function pad 112 is connected to the first function bonding wire 212, and the other end of the first function bonding wire 212 is in contact with the metal wiring layer 400, the various electrical connection requirements of the first function pad 112 (for example, electrical connection with other pads 100 through the metal wiring layer 400, external lead through the metal wiring layer 400, etc.) can be met. Thus, the MEMS sensor packaging structure occupies a small space and has small signal loss, and not only the formation of the bonding wire connected to all pads 100 can be completed in the chip-level packaging process, but also the high degree of freedom of the electrical connection mode of the first chip 10 and the second chip 20 is taken into account.

[0054] The material of the auxiliary bonding wire 201 and the material of the first function bonding wire 212 are the same, and both include gold, aluminum, or copper, etc.

[0055] Since the auxiliary bonding wire 201 and the first functional bonding wire 212 are formed by breaking the same bonding wire after grinding, in some embodiments, the corresponding auxiliary bonding wire 201 and the first functional bonding wire 212 not only are adjacent, but also are obliquely opposite.

[0056] In some embodiments, the plurality of pads 100 on the first chip 10 are distributed around the second chip 20, and the two pads 100 having the corresponding relationship are adjacent to each other on the two orthographic projections of the surface of the first chip 10. That is, between the two orthographic projections of the two pads 100 having the corresponding relationship on the surface of the first chip 10, there is no projection of other pads 100.

[0057] In the present embodiment, the MEMS sensor packaging structure further comprises a plastic encapsulation layer 300.

[0058] The plastic encapsulation layer 300 is arranged on the surface of the first chip 10, and the plastic encapsulation layer 300 covers the second chip 20.

[0059] The plurality of pads 100, the auxiliary bonding wire 201 and the first functional bonding wire 212 are all located in the plastic encapsulation layer 300, and the other end of the auxiliary bonding wire 201 and the other end of the first functional bonding wire 212 are exposed on the surface of the plastic encapsulation layer 300.

[0060] Since the auxiliary bonding wire 201 and the first functional bonding wire 212 are formed by breaking the same bonding wire after grinding, the other ends of the two are exposed on the surface of the plastic encapsulation layer 300.

[0061] In the present embodiment, the MEMS sensor packaging structure further comprises an insulating layer 500.

[0062] The insulating layer 500 is arranged on the surface of the plastic encapsulation layer 300, and covers the other end of the auxiliary bonding wire 201. Thus, the other end of the auxiliary bonding wire 201 is open.

[0063] In addition, the metal wiring layer 400 is arranged on the surface of the plastic encapsulation layer 300 and located in the insulating layer 500, and the other end of the first functional bonding wire 212 is exposed on the surface of the plastic encapsulation layer 300 and contacts the bottom surface of the metal wiring layer 400.

[0064] The material of the metal wiring layer 400 includes a laminated metal of titanium and copper, or a laminated metal of titanium and gold.

[0065] In some embodiments, the insulating layer 500 includes a first insulating layer 510 and a second insulating layer 520.

[0066] The first insulating layer 510 is located on the surface of the plastic sealing layer 300, the metal wiring layer 400 is located on the surface of the plastic sealing layer 300 and the surface of the first insulating layer 510, and the second insulating layer 520 is located on the surface of the first insulating layer 510 and the surface of the metal wiring layer 400.

[0067] The material of the first insulating layer 510 is an organic material.

[0068] Specifically, the material of the first insulating layer 510 is a polyimide material.

[0069] The material of the second insulating layer 520 is an organic material.

[0070] Specifically, the material of the second insulating layer 520 is a polyimide material.

[0071] In the embodiment, a plurality of solder balls 610 are further arranged above the insulating layer 500, and a solder ball lower metallization layer 620 is connected between the solder balls 610 and the metal wiring layer 400.

[0072] In the embodiment, the first functional bonding lead 212 is electrically connected to other electrical components through the metal wiring layer 400, the solder ball lower metallization layer 620, and the solder balls 610.

[0073] In other embodiments, the first functional bonding lead 212 can be electrically connected to the bonding lead connected to the pad 100 other than the auxiliary pad 101 through the metal wiring layer 400, so as to realize the electrical interconnection between the first chip 10 and the second chip 20.

[0074] The material of the solder ball lower metallization layer 620 includes a laminated metal of titanium, copper, and nickel, or a laminated metal of titanium, nickel, and gold, or a laminated metal of titanium, copper, and nickel.

[0075] The solder balls 610 include a silver-tin alloy.

[0076] It should be noted that, Figure 1 In order to facilitate understanding, the plastic sealing layer 300, the metal wiring layer 400, the insulating layer 500, the solder balls 610, the solder ball lower metallization layer 620, and the adhesive layer 700 are not shown.

[0077]

Embodiment Two

[0078] Please refer to Figure 3 and Figure 4 The difference between the embodiment and the embodiment one is that the auxiliary pad 102 arranged on the second chip 20 is arranged instead of the auxiliary pad 101 arranged on the first chip 10, and the first functional pad 111 arranged on the first chip 10 is arranged instead of the first functional pad 112 arranged on the second chip 20.

[0079] Correspondingly, the number of the auxiliary pads 102 can be one, two or more.

[0080] For the convenience of description, Figure 3 One auxiliary pad 102 is schematically represented in FIG. 1.

[0081] In addition, the correspondence between the auxiliary pad 102 and the first functional pad 111 can be one-to-one as shown in FIG. 1, or one auxiliary pad 102 can correspond to two or more first functional pads 111, or one first functional pad 111 can correspond to two or more auxiliary pads 102. Figure 3

[0082] Correspondingly, one end of the auxiliary bonding wire 202 is connected to the auxiliary pad 102, and the other end of the auxiliary bonding wire 202 is open. In other embodiments, the other end of the auxiliary bonding wire 202 is coupled to a ground terminal.

[0083] Correspondingly, the first functional pad 111 is connected to the first functional bonding wire 211, and the other end of the first functional bonding wire 211 is in contact with the metal wiring layer 400.

[0084] Thus, a more free and rich electrical connection structure mode is provided for the MEMS sensor packaging structure.

[0085] Of course, in other embodiments, the auxiliary pad 101 provided on the first chip 10, the auxiliary pad 102 provided on the second chip 20, the first functional pad 111 provided on the first chip 10, and the first functional pad 112 provided on the second chip 20 can be simultaneously provided. Correspondingly, the auxiliary bonding wire 201, the auxiliary bonding wire 202, the first functional bonding wire 211 and the first functional bonding wire 212 can also be simultaneously provided.

[0086] It should be noted that, similar to Figure 1 , Figure 3 For the convenience of understanding, the plastic encapsulation layer 300, the metal wiring layer 400, the insulating layer 500, the solder ball 610, the solder ball lower metallization layer 620 and the adhesive layer 700 are not shown in FIG. 1.

[0087]

Embodiment Three

[0088] Please refer to FIG. 5 and Figure 6 The difference between the present embodiment and the second embodiment is that the plurality of pads further include a corresponding second functional pad 120 and a third functional pad 130, and the corresponding second functional pad 120 and the third functional pad 130 are respectively connected to two ends of the second functional bonding wire 220.

[0089] ​The second functional bonding wire 220 is covered by the plastic encapsulation layer 300.

[0090] The second functional bonding wire 220 is covered by the plastic encapsulation layer 300.

[0091] That is to say, in the present embodiment, the MEMS sensor packaging structure not only has the auxiliary bonding wire 201 and the first functional bonding wire 212, but also has the second functional bonding wire 220 below the top of the auxiliary bonding wire 201 and the first functional bonding wire 212, and the electrical interconnection between the first chip 10 and the second chip 20 can be directly realized through the second functional bonding wire 220 in the plastic encapsulation layer 300. Therefore, a more free and rich electrical connection structure mode is provided for the MEMS sensor packaging structure.

[0092] It should be noted that, similar to Figure 1 , Figure 5 In order to facilitate understanding, the case of three auxiliary pads 102 is schematically represented, and the plastic encapsulation layer 300, the metal wiring layer 400, the insulating layer 500, the solder ball 610, the solder ball lower metallization layer 620 and the adhesive layer 700 are not schematically represented.

[0093]

Embodiment Four

[0094] Please refer to Figure 7 and Figure 8 The difference between the present embodiment and the embodiment two is that the plurality of pads further include a corresponding fourth functional pad 140 and a fifth functional pad 150, the fourth functional pad 140 is connected to one end of the third functional bonding wire 230, the fifth functional pad 150 is connected to one end of the fourth functional bonding wire 240, and the other end of the third functional bonding wire 230 and the other end of the fourth functional bonding wire 240 are both in contact with the metal wiring layer 400, so that the third functional bonding wire 230 and the fourth functional bonding wire 240 are electrically interconnected based on the metal wiring layer 400.

[0095] The fourth functional pad 140 is arranged on the first chip 10, and the fifth functional pad 150 is arranged on the second chip 20.

[0096] That is to say, in the present embodiment, the electrical interconnection between the first chip 10 and the second chip 20 can be directly realized through the metal wiring layer 400. Therefore, a more free and rich electrical connection structure mode is provided for the MEMS sensor packaging structure.

[0097] It should be noted that, Figure 7For the convenience of understanding, the case that one auxiliary pad 102 corresponds to two or more first function pads 111 is schematically represented, and the plastic encapsulation layer 300, the insulating layer 500, the soldering ball 610, the metalization layer 620 under the soldering ball, and the adhesive layer 700 are not schematically represented, and only the part of the metal wiring layer 400 connecting the third function bonding lead 230 and the fourth function bonding lead 240 is schematically represented.

[0098] Figures 9 to 20 The utility model discloses a forming method of the MEMS sensor package structure, and the utility model discloses a forming method of the MEMS sensor package structure.

[0099] Please refer to Figure 9 And Figure 10 , Figure 9 It is the overhead structure schematic diagram of first wafer 11, Figure 10 It is Figure 9 The cross section schematic diagram of 11 is provided with first chip 10 in matrix arrangement on first wafer 11, and first chip 10 is provided with pad 100.

[0100] In some embodiments, the first chip 10 is an ASIC chip.

[0101] Please refer to Figure 11 A plurality of second chips 20 are provided, and the second chip 20 is provided with pad 100.

[0102] The second chip 20 is a single chip formed based on cutting and separating the second wafer.

[0103] In some embodiments, the second chip 20 is a MEMS sensor chip.

[0104] Please refer to Figure 12 One second chip 20 is stacked on each first chip 10.

[0105] The first chip 10 and the second chip 20 are bonded.

[0106] Specifically, the second chip 20 is attached to the first chip 10 through the adhesive layer 700.

[0107] In addition, the pad 100 arranged on the first chip 10 and the pad 100 arranged on the second chip 20 constitute a plurality of pads 100 of the MEMS sensor package structure. And the plurality of pads 100 include corresponding auxiliary pads 101 and first function pads 112, that is to say, the auxiliary pad 101 and the first function pad 112 are both specific pads 100 in the plurality of pads 100.

[0108] By arranging the auxiliary pads 101 in the plurality of pads 100, each pad 100 in the plurality of pads 100 corresponds to at least one of the remaining pads 100, and thus, when the chip-level package is formed by stacking the first chip 10 and the second chip 20, the formation of the bonding wires can be directly completed on all pads 100 of the first chip 10 and all pads 100 of the second chip 20.

[0109] In the present embodiment, the auxiliary pads 101 are arranged on the first chip 10, the first functional pads 112 are arranged on the second chip 20, and the number of the auxiliary pads 101 is more than one, and the number of the first functional pads 112 is more than one.

[0110] Please refer to Figure 13 and Figure 14 , by the bonding wire process, the initial bonding wires 200 are formed between the pads 100 having the corresponding relationship.

[0111] Need to be explained, Figure 14 schematically shows some forms of the initial bonding wires 200 different from Figure 13 . For the convenience of explanation, the subsequent steps are described based on the form of the initial bonding wires 200 shown in Figure 13 .

[0112] In other embodiments, according to actual design requirements, the second functional bonding wires 220 (as shown in Figure 6 ) having a height lower than that of the initial bonding wires 200 can also be formed. Since the height of the second functional bonding wires 220 is lower than that of the initial bonding wires 200, when the initial bonding wires 200 are truncated by the subsequent grinding process, the second functional bonding wires 220 are not truncated.

[0113] At the same time, for the convenience of distinguishing and understanding, the two pads 100 in the plurality of pads 100 connected to the two ends of the second functional bonding wires 220 are defined as the second functional pads 120 and the third functional pads 130. That is to say, the plurality of pads further include the plurality of second functional pads 120 and the plurality of third functional pads 130, and the two ends of the second functional bonding wires 220 are respectively connected to the corresponding second functional pads 120 and the third functional pads 130.

[0114] The material of the initial bonding wires 200 includes gold, aluminum, copper, etc.

[0115] Please refer to Figure 15 , the initial plastic encapsulation layer 301 is formed on the surfaces of the first wafer 11, the second chip 20, the plurality of pads 100 and the plurality of initial bonding wires 200, and the top surface of the initial plastic encapsulation layer 301 is higher than the top end of the initial bonding wires 200, so as to cover the initial bonding wires 200.

[0116] Please refer to Figure 16 The initial plastic encapsulation layer 301 and the initial bonding lead 200 are ground until the initial bonding lead 200 is cut off, forming the plastic encapsulation layer 300.

[0117] By cutting off the initial bonding lead 200, a one-to-one correspondence between the auxiliary bonding lead 201 and the first functional bonding lead 212 is formed.

[0118] In some embodiments, since the auxiliary bonding lead 201 and the first functional bonding lead 212 are formed by cutting off the same initial bonding lead 200 after grinding, the corresponding auxiliary bonding lead 201 and the first functional bonding lead 212 are not only adjacent, but also inclined towards each other.

[0119] The auxiliary pad 101 is connected to one end of the auxiliary bonding lead 201, and the other end of the auxiliary bonding lead 201 is exposed on the surface of the plastic encapsulation layer 300.

[0120] The first functional pad 112 is connected to one end of the first functional bonding lead 212, and the other end of the first functional bonding lead 212 is exposed on the surface of the plastic encapsulation layer 300.

[0121] In other embodiments, the second functional bonding lead 220 (as shown in Figure 6 ) is not exposed by the plastic encapsulation layer 300.

[0122] Please refer to Figure 17 , a first insulating layer 510 is formed on the surface of the plastic encapsulation layer 300.

[0123] The first insulating layer 510 is patterned based on a photolithography process.

[0124] The first insulating layer 510 covers the other end of the auxiliary bonding lead 201, thereby opening the other end of the auxiliary bonding lead 201.

[0125] In addition, the first insulating layer 510 has an opening 511 therein, and the opening 511 exposes the other end of the first functional bonding lead 212.

[0126] In other embodiments, the first insulating layer also exposes the other end of the auxiliary bonding lead 201, so as to couple the other end of the auxiliary bonding lead 201 with a ground terminal.

[0127] The material of the first insulating layer 510 is an organic material.

[0128] Specifically, the material of the first insulating layer 510 is a polyimide material.

[0129] Please refer to Figure 18A metal wiring layer 400 is formed on the surface of the molding compound 300 and within the opening 511. This allows the other end of the first functional bonding lead 212 to be exposed on the surface of the molding compound 300 and then contact the bottom surface of the metal wiring layer 400.

[0130] The material of the metal wiring layer 400 includes a multilayer metal of titanium and copper, or a multilayer metal of titanium and gold.

[0131] Please refer to Figure 19 A second insulating layer 520 is formed on the surface of the first insulating layer 510 and the surface of the metal wiring layer 400.

[0132] The first insulating layer 510 and the second insulating layer 520 constitute the insulating layer 500.

[0133] The second insulating layer 520 is patterned using processes such as photolithography.

[0134] The second insulating layer 520 has an opening 521 that exposes part of the surface of the metal wiring layer 400.

[0135] The material of the second insulating layer 520 is an organic material.

[0136] Specifically, the material of the second insulating layer 520 is a polyimide-based material.

[0137] Please refer to Figure 20 A solder ball under-metallization layer 620 is formed inside the opening 521 and on the surface of the second insulating layer 520, and a solder ball 610 is formed on the surface of the solder ball under-metallization layer 620.

[0138] The material of the metallization layer 620 under the solder ball includes a multilayer metal of titanium, copper, nickel and gold, or a multilayer metal of titanium, nickel and gold, or a multilayer metal of titanium, copper and nickel.

[0139] Solder ball 610 includes a silver-tin alloy.

[0140] Next, after forming the solder balls 610, a wafer dicing process is performed to form... Figure 1 The MEMS sensor package structure shown includes a first chip 10 and a second chip 20 thereon.

[0141] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A MEMS sensor package structure, characterized by, The application relates to a chip structure and a manufacturing method thereof. The chip structure comprises a first chip and a second chip stacked on the first chip; a plurality of pads arranged on the first chip and the second chip, wherein the pads comprise corresponding auxiliary pads and first functional pads, the auxiliary pads are connected to one end of auxiliary bonding wires, the other end of the auxiliary bonding wires is open or coupled to a ground terminal, the first functional pads are connected to first functional bonding wires, the other end of the first functional bonding wires is in contact with a metal wiring layer, and the auxiliary bonding wires and the first functional bonding wires are in one-to-one correspondence. The surface of the first chip is provided with a plastic sealing layer, the plastic sealing layer covers the second chip, the plurality of pads, the auxiliary bonding wires and the first functional bonding wires are located in the plastic sealing layer, and the surface of the plastic sealing layer exposes the other end of the auxiliary bonding wires and the other end of the first functional bonding wires.

2. The MEMS sensor package structure of claim 1, wherein, The corresponding auxiliary bonding wires are adjacent to the first functional bonding wires and are inclined towards each other.

3. The MEMS sensor package structure of claim 2, wherein, The plurality of pads further comprise corresponding second functional pads and third functional pads, the second functional pads are arranged on the first chip, the third functional pads are arranged on the second chip, and the corresponding second functional pads and third functional pads are respectively connected to two ends of second functional bonding wires, and the second functional bonding wires are covered by the plastic sealing layer.

4. The MEMS sensor package structure of claim 2, wherein, The surface of the plastic sealing layer is provided with an insulating layer, and the insulating layer covers the other end of the auxiliary bonding wires.

5. The MEMS sensor package structure of claim 2, wherein, The metal wiring layer is arranged on the surface of the plastic sealing layer and located in the insulating layer, and the other end of the first functional bonding wires is in contact with the bottom surface of the metal wiring layer.

6. The MEMS sensor package structure of claim 5, wherein, The insulating layer comprises a first insulating layer and a second insulating layer, the first insulating layer is located on the surface of the plastic sealing layer, the metal wiring layer is also located on the surface of the first insulating layer, the second insulating layer is located on the surfaces of the first insulating layer and the metal wiring layer, a plurality of solder balls are further arranged above the insulating layer, and a solder ball lower metallization layer is connected between the solder balls and the metal wiring layer.

7. The MEMS sensor package structure of claim 6, wherein, The plurality of pads further comprise corresponding fourth functional pads and fifth functional pads, the fourth functional pads are arranged on the first chip, the fifth functional pads are arranged on the second chip, the fourth functional pads are connected to one end of third functional bonding wires, the fifth functional pads are connected to one end of fourth functional bonding wires, the other end of the third functional bonding wires and the other end of the fourth functional bonding wires are both in contact with the metal wiring layer, and the third functional bonding wires and the fourth functional bonding wires are electrically interconnected based on the metal wiring layer.

8. The MEMS sensor package structure of claim 1, wherein, The pads arranged on the first chip are distributed around the second chip, and two pads with a corresponding relationship are adjacent to two orthographic projections on the surface of the first chip.

9. The MEMS sensor package structure of claim 1, wherein, The first chip is an ASIC chip, the second chip is a MEMS sensor chip, and the first chip and the second chip are bonded.

10. The MEMS sensor package structure according to any one of claims 1-9, wherein, ​

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