CN-122028766-A - Wire bonding method and system for chip package integrated with stacked suspension structure

CN122028766ACN 122028766 ACN122028766 ACN 122028766ACN-122028766-A

Abstract

The invention discloses a wire bonding method and a wire bonding system for chip packaging of an integrated stacked suspended structure, and relates to the technical field of semiconductor packaging; the method comprises the steps of obtaining deformation data corresponding to all welding spots, wherein the deformation data are obtained by respectively collecting displacement responses of a reference point and the corresponding welding spot under a plurality of preset contact forces to obtain discrete data pairs formed by the contact force and the deformation, establishing a mapping relation between the contact force and the deformation of each welding spot through a fitting algorithm based on the discrete data pairs corresponding to each welding spot to obtain a position compensation factor, calculating a position compensation value according to the target contact force of the current welding spot and the corresponding position compensation factor in the wire bonding process, and carrying out compensation motion according to the position compensation value before executing arc pulling action to adjust the initial height of a wire arc, so that the problem of unstable welding quality caused by material suspension deformation is solved, and the robustness and the production efficiency of the wire arc motion are improved.

Inventors

YAN YIJUN
HE YUNBO
Ji Haizhong
YE WENTAO
LIU JUNJIE

Assignees

广东阿达半导体设备股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (10)

1. A wire bonding method for chip packages integrated with stacked suspension structures, comprising: Acquiring deformation data corresponding to all welding spots, wherein the deformation data is obtained by respectively acquiring displacement responses of a datum point and the corresponding welding spot under a plurality of preset contact forces to obtain discrete data pairs consisting of the contact forces and the deformation; Based on each welding spot, establishing a mapping relation between the contact force and the deformation of the welding spot through a fitting algorithm according to the corresponding discrete data pair to obtain a position compensation factor; in the wire bonding process, calculating a position compensation value according to the target contact force of the current welding spot and a corresponding position compensation factor, and controlling the bonding head to perform compensation movement according to the position compensation value before performing arc discharge action so as to adjust the initial height of the wire arc.
2. The method for wire bonding of a chip package integrated with a stacked suspension structure of claim 1, wherein the obtaining deformation data corresponding to all solder joints comprises: defining deformation quantity, namely respectively acquiring the positions of a datum point and the positions of corresponding welding spots under the preset contact force, calculating a displacement difference value between the datum point and the corresponding welding spots, and taking the displacement difference value as the deformation quantity of the welding spots under the contact force; The method comprises the steps of collecting a data set under single contact force, namely controlling a bonding head to sequentially contact each welding spot with a first preset contact force, obtaining the deformation quantity of each welding spot under the first preset contact force, and summarizing to obtain a first discrete data set, wherein the first discrete data set comprises the first preset contact force and deformation quantity sets of all corresponding welding spots; and acquiring data sets under multiple contact forces, namely sequentially changing preset contact forces, controlling the bonding head to repeatedly execute the step of acquiring the data sets under single contact force by using a plurality of different preset contact forces to obtain a plurality of discrete data sets, wherein each discrete data set corresponds to one preset contact force and comprises the preset contact force and deformation amount sets of all corresponding welding spots.
3. The wire bonding method for integrated stacked floating structure chip package of claim 2 wherein said fitting algorithm is a least squares or higher order polynomial fitting method.
4. The method of claim 2, wherein the mapping between the contact force and the deformation is characterized by a first order linear function, wherein the deformation is equal to the contact force multiplied by the slope of the fitting curve and added to the offset.
5. The wire bonding method for integrated stacked floating structure chip package of claim 2, wherein the mapping relationship between the contact force and the deformation amount is characterized by a higher order polynomial function, i.e. the deformation amount is expressed as a higher order polynomial function of the contact force.
6. The method of claim 1, further comprising visually locating each solder joint by visual template matching before obtaining deformation data corresponding to all solder joints.
7. The wire bonding method for integrated stacked suspension chip package of claim 1, wherein a displacement difference between the fiducial and the corresponding bond pad is obtained by measuring an actual position of the bond head with a displacement sensor.
8. The wire bonding method for chip packages integrated with stacked suspension of claim 1, wherein the compensation motion is a displacement adjustment along the Z-axis for counteracting variation in deformation due to the chip stacked suspension.
9. A wire bonding system for integrated stacked floating structure chip packages for implementing a wire bonding method for integrated stacked floating structure chip packages according to any one of claims 1 to 8, comprising: The upper computer is used for sending out a control instruction, and executing the processing of deformation data, the establishment of a mapping relation, the calculation of a position compensation value and the application of the compensation value; The motion control card is in communication connection with the upper computer and is used for sending a position instruction according to the control instruction of the upper computer and controlling the bonding head to move according to a preset track; the bonding head is in communication connection with the motion control card and is used for executing wire bonding operation and compensating motion according to the position instruction; And the displacement sensor is arranged on the bonding head and is used for measuring the actual position of the bonding head in the contact process and feeding back measurement data to the upper computer.
10. The system of claim 9, further comprising a vision positioning module communicatively coupled to the host computer for visually positioning each solder joint via template matching and transmitting the positioning result to the host computer for generating a motion profile.

Description

Wire bonding method and system for chip package integrated with stacked suspension structure Technical Field The invention relates to the technical field of semiconductor packaging, in particular to a wire bonding method and a wire bonding system for chip packaging of an integrated stacked suspended structure. Background As semiconductor chips continue to develop toward higher density and higher performance, stacking multiple semiconductor chips or multiple semiconductor packages in a single semiconductor package has become a dominant technological path for increasing integration density. In the three-dimensional stacked packaging structure, chips are integrated in a suspended stacking mode, and a plurality of chips are sequentially stacked in the vertical direction to form a complex space interconnection structure. However, in conventional wire bonding processes, the bonding head is typically bonded with a constant depth of depression or constant contact force as the contact pads are bonded. For the chip package of the integrated stacked suspension structure, as the chips of each layer are in a suspension state, the mechanical supporting rigidity of the chips is obviously different, so that the welding spots at different positions can generate deformation amounts of different degrees under the action of the same contact force. Such variation can directly affect the accuracy of the wire-arc initiation height, and thus the uniformity of the bonding quality. In the prior art, no effective solution has been proposed for this problem. Part of the process compensates for the variation in deformation by increasing the contact force or extending the welding time, but this approach tends to result in solder joint overpressure damage or reduced bond quality. Therefore, how to perform personalized compensation for the deformation characteristics of different solder joints in the chip package with integrated stacked suspension structure becomes a technical problem to be solved in the field. Disclosure of Invention Aiming at solving the technical problems of unstable bonding quality caused by abnormal wire arc track due to elastic deformation at a material welding spot caused by a suspension structure when a chip with an integrated stacked suspension structure is prepared by a wire bonding process in the prior art, the invention provides a wire bonding method and a system for chip packaging with the integrated stacked suspension structure, the method comprises the steps of establishing a mapping relation between contact force and deformation quantity by measuring deformation characteristics of each welding spot in advance, and performing personalized position compensation according to target contact force in the bonding process so as to eliminate deformation quantity difference caused by a chip suspension structure; therefore, the bonding stability of the device to the chips of the integrated stacked suspended structure is obviously improved while the production efficiency is not affected. The technical proposal is as follows: In one aspect, a wire bonding method for chip packages integrated with stacked suspension structures is provided, comprising: Acquiring deformation data corresponding to all welding spots, wherein the deformation data is obtained by respectively acquiring displacement responses of a datum point and the corresponding welding spot under a plurality of preset contact forces to obtain discrete data pairs consisting of the contact forces and the deformation; Based on each welding spot, establishing a mapping relation between the contact force and the deformation of the welding spot through a fitting algorithm according to the corresponding discrete data pair to obtain a position compensation factor; in the wire bonding process, calculating a position compensation value according to the target contact force of the current welding spot and a corresponding position compensation factor, and controlling the bonding head to perform compensation movement according to the position compensation value before performing arc discharge action so as to adjust the initial height of the wire arc. According to a further technical scheme, the obtaining of deformation data corresponding to all welding spots comprises the following steps: defining deformation quantity, namely respectively acquiring the positions of a datum point and the positions of corresponding welding spots under the preset contact force, calculating a displacement difference value between the datum point and the corresponding welding spots, and taking the displacement difference value as the deformation quantity of the welding spots under the contact force; The method comprises the steps of collecting a data set under single contact force, namely controlling a bonding head to sequentially contact each welding spot with a first preset contact force, obtaining the deformation quantity of each welding spot under the first preset contact force, and summa