CN-122017214-A - Device and method for testing curing shrinkage of component polymer packaging material

CN122017214ACN 122017214 ACN122017214 ACN 122017214ACN-122017214-A

Abstract

The invention relates to a device and a method for testing solidification shrinkage of a component polymer packaging material, wherein the device comprises a front template, a rear template, screws and a sensing system, wherein the front template and the rear template are in butt joint through a concave-convex step embedded structure and form a die with an injection channel, a testing cavity and an exhaust channel, the screws are arranged at two outer sides and lower parts of the testing cavity, the screws sequentially penetrate through corresponding positions of a circular gasket, a spring gasket, the front die and the rear die horizontally and then are fastened with nuts, and the sensing system is connected with a polymer to be tested in the testing cavity and obtains an original signal of the whole period from liquid encapsulation, gelation and hardening molding of the polymer. The invention has the beneficial effects that the leakage problem of the low-viscosity packaging material in the initial stage of high-temperature curing is effectively solved. The applicable scene of the device is greatly expanded. And provides complete data support for optimizing the packaging process. The physical intrinsic shrinkage of the material is obtained.

Inventors

YANG DAOGUO
Zhan Zhuangchao
Liang Miaoqi
WANG YUPENG
QIN HONGBO
CAI MIAO
WEI QIQIN
WANG XIYOU

Assignees

桂林电子科技大学

Dates

Publication Date: 20260512
Application Date: 20260210

Claims (9)

1. The device for testing the solidification shrinkage of the component polymer packaging material is characterized by comprising a front template (1), a rear template (2), a screw (7) and a sensing system, wherein the front template (1) and the rear template (2) are in butt joint through a concave-convex step embedded structure and form a die with an injection channel, a testing cavity and an exhaust channel, the injection channel is communicated with the top of the testing cavity and is used for injecting a polymer (4) to be tested into the testing cavity, the exhaust channel is communicated with the bottom of the testing cavity and is used for exhausting gas outwards when the polymer (4) to be tested is injected, the screw (7) is provided with a plurality of screws (7) which are arranged at two outer sides and the lower part of the testing cavity, and the screw (7) sequentially horizontally penetrates through a circular gasket (6), a spring gasket (5), the front die (1) and the rear die (2) in corresponding positions and is fastened with a nut (8); The sensing system is connected with the polymer (4) to be tested in the testing cavity, and obtains an original signal of the whole period from liquid encapsulation, gelation to hardening and molding of the polymer.
2. The device for testing the solidification shrinkage of the component polymer packaging material according to claim 1, wherein the sensing system comprises an optical fiber, a thermocouple, a multichannel fiber bragg grating demodulator and a multichannel temperature tester, wherein the bragg grating is written in advance, the optical fiber and the thermocouple are vertically inserted into the center of the testing cavity, the tail end of the optical fiber is connected to the multichannel fiber bragg grating demodulator, a signal wire of the thermocouple is connected to the multichannel temperature tester, and the multichannel fiber bragg grating demodulator and the multichannel temperature tester are connected with a computer through serial port connecting wires.
3. The device for testing the solidification shrinkage of the polymer packaging material of the component according to claim 1, wherein the die is provided with two sets, and the sensing system comprises an optical fiber with the Bragg grating written in advance, a multichannel fiber bragg grating demodulator and a fused quartz capillary glass tube (3), wherein the optical fiber is provided with two sets; vertically inserting the fused silica capillary glass tube (3) in the center of a test cavity of a first set of the die, wherein a first optical fiber passes through the fused silica capillary glass tube (3), and the tail end of the first optical fiber is connected to the multichannel fiber bragg grating demodulator; A second optical fiber is vertically inserted into the center of the testing cavity of the second set of the die, and the tail end of the second optical fiber is connected to the multichannel fiber bragg grating demodulator.
4. A curing shrinkage testing device for polymer packaging materials of components according to any one of claims 1 to 3, wherein the inner wall of the testing cavity is made of polytetrafluoroethylene or is coated with polytetrafluoroethylene coating.
5. A method for testing the cure shrinkage of a polymer encapsulating material for a component, which is used in the cure shrinkage testing apparatus for a polymer encapsulating material for a component according to any one of claims 1 to 3, comprising the steps of: step 1, constructing a high-tightness precise forming environment to obtain a stable test cavity without leakage; Step2, based on the stable test cavity obtained in the step 1, integrating and arranging a temperature and pressure synchronous sensing system or a dual-module contrast compensation sensing system according to the hardware conditions of a laboratory, so as to adapt to different hardware environments; Step 3, synchronously collecting full-period data of the polymer from liquid filling and sealing, gelation to hardening molding based on the non-leakage cavity in the step 1 and the sensing system corresponding to the step 2, and obtaining an original signal; And 4, based on the original signal in the step 3, decoupling and calculating the physical intrinsic shrinkage of the polymer to be detected, and obtaining a precise result.
6. The device for curing shrinkage testing of the component polymer packaging material according to claim 5 is characterized in that step 1 is specifically that a front template (1) and a rear template (2) are butted through a concave-convex step embedded structure to form a die with an injection channel, a testing cavity and an exhaust channel, a plurality of screws (7) arranged at the two outer sides and the lower part of the testing cavity are adopted, the screws (7) sequentially penetrate through a circular gasket (6), a spring gasket (5) and the corresponding positions of the front template (1) and the rear template (2) horizontally, nuts (8) are fastened, and meanwhile, polytetrafluoroethylene materials or polytetrafluoroethylene coating is sprayed on the inner wall of the testing cavity.
7. The device for testing the curing shrinkage of the polymer packaging material of the component according to claim 6, wherein the temperature and pressure synchronous sensing system integrated and arranged in the step 2 is specifically: Vertically inserting an optical fiber with a Bragg grating written in advance into the center of the test cavity together with a thermocouple, wherein the optical fiber is in direct contact with a polymer, and the thermocouple is used for acquiring temperature data in real time; the tail end of the optical fiber is connected with a multi-channel fiber bragg grating demodulator, a signal wire of the thermocouple is connected with a multi-channel temperature tester, and the multi-channel fiber bragg grating demodulator and the multi-channel temperature tester are connected with a computer through serial port connecting wires to form a temperature and pressure synchronous acquisition channel; in the step2, the integrated and laid dual-module contrast compensation sensing system specifically comprises: And starting two sets of dies, wherein a fused quartz capillary glass tube (3) is arranged at the center of a test cavity of one set of die, a first optical fiber passes through the fused quartz capillary glass tube (3), and a second optical fiber is vertically inserted into the center of the test cavity of the other set of die, so that the second optical fiber directly contacts with the polymer, and the optical fibers of the two sets of dies are connected to an optical fiber grating demodulator to form a dual-sensing control channel.
8. The device for curing shrinkage testing of polymer packaging material for components of claim 7, wherein step 3 comprises: Step 3.1, glue solution treatment and pouring, namely placing the prepared polymer glue solution into a vacuum drying oven for defoaming, and then pouring the polymer glue solution into a test cavity through a pouring channel at the top of the die, wherein an exhaust channel is exhausted in the pouring process until the test cavity is filled with the polymer glue solution; And 3.2, solidifying and data acquisition, namely placing the die in a vacuum drying oven with controlled environment, starting solidifying according to a preset process, starting a computer end acquisition program, capturing the change of the central wavelength of the optical fiber in real time through a fiber grating demodulator under a temperature and pressure synchronous sensing system, simultaneously recording real-time temperature data of a thermocouple, synchronously acquiring the change data of the central wavelength of the optical fiber of two sets of die under a dual-die contrast compensation sensing system, and finally obtaining an original signal of the whole period from liquid encapsulation, gelation to hardening and forming of the polymer.
9. The device for curing shrinkage testing of polymer packaging material for components of claim 7, wherein step 4 comprises: under the temperature and pressure synchronous sensing system, the center wavelength lambda of the fiber grating is influenced by chemical shrinkage and temperature T, and the calculation formula of the changed center wavelength delta lambda is as follows: ; Wherein Deltalambda c is the central wavelength change caused by curing shrinkage, deltalambda T is the central wavelength change caused by temperature, k c is the curing shrinkage sensitivity coefficient, epsilon c is the curing shrinkage rate of the polymer to be tested, k T is the temperature sensitivity coefficient, deltaT is the temperature change measured by a thermocouple, computer software calibrates the temperature sensitivity coefficient of the optical fiber by constant-rate temperature rise according to the temperature change fed back by the thermocouple, or deducts the thermal expansion central wavelength drift of the optical fiber caused by temperature rise in real time according to the central wavelength change fed back by the optical fiber, calculates the central wavelength drift purely caused by curing shrinkage of the polymer by compensation, and the curing shrinkage rate of the polymer to be tested can be calculated by the following formula: ; ; ; ; Wherein lambda B is Bragg wavelength, P k is the special optical constant of the fiber Bragg grating, n eff is effective refractive index, lambda is the distance between Bragg gratings, P 12 and P 11 are strain optical constants, and v f is the Poisson's ratio of the fiber; Under the dual-mold contrast compensation sensing system, the wavelength variation delta lambda T of a mold with the fused quartz capillary glass tube (3) is extracted by utilizing the strain shielding principle of the fused quartz capillary glass tube (3), the delta lambda T in the mold wavelength variation of the non-fused quartz capillary glass tube (3) is contrasted and subtracted to obtain the central wavelength variation delta lambda c caused by curing shrinkage, and finally the linear curing shrinkage epsilon c ：ε c =Δλ c /k c of the polymer to be tested is calculated by combining the curing shrinkage sensitivity coefficient k c through the following formula.

Description

Device and method for testing curing shrinkage of component polymer packaging material Technical Field The invention belongs to the field of polymer curing shrinkage test, and particularly relates to a device and a method for testing curing shrinkage of a component polymer packaging material. Background With the evolution of High Performance Computing (HPC) and heterogeneous integration technologies, component packaging is moving towards an era of extremely high interconnect density and extremely narrow gap. In this process, the polymer encapsulating material (e.g., epoxy, adhesive, etc.) acts as a medium for stress transfer, and its volumetric behavior during the curing stage directly determines the yield. This irreversible volume reduction is the initiator of cracking of the inner layers of the chip, solder ball migration and interfacial debonding due to chemical shrinkage associated with molecular chain polycondensation as the polymer transitions from liquid monomer to the curing network. Thus, accurately capturing the real-time cure shrinkage characteristics of the encapsulation material within the micrometer scale has become a key cornerstone for evaluating the residual strain distribution during the chip design stage. The existing curing shrinkage monitoring means show serious systematic blind areas under a complex process environment, and the quantitative requirement of precise packaging on the evolution characteristics of materials is difficult to meet. First, capture of the "flow-standing" critical state at the early phase transition is missing. The conventional specific volume method or pressure-volume-temperature test method is mostly dependent on a closed pressure cavity, and when the polymer is in a low-viscosity fluid in the initial curing stage, the contact pressure between the sealing logic of the die cavity and a sensor often interferes with the natural flow of the glue solution, so that characteristic data near a gel point is shielded by system noise. Second, the "pseudo strain" decoupling problem induced by the curing exotherm. The curing of polymers is a severe exothermic process and localized temperature increases can lead to instantaneous thermal expansion of the material. The current mainstream optical sensing scheme has high sensitivity, but often superposes positive displacement generated by thermal expansion and negative displacement generated by curing shrinkage, if a very severe and synchronous temperature compensation mechanism is lacking, the measured shrinkage curve contains a large amount of thermal distortion components, and the chemical intrinsic shrinkage rule of the material cannot be reduced. Finally, "boundary leakage" and test failure in process adaptations. In order to pursue a thinner package thickness, the new glue solution has extremely strong permeability. The existing test dies are connected by adopting simple planes, and when the dies are heated and heated to cause uneven thermal expansion, micro leakage can be inevitably generated in the butt joint gaps. The loss of the trace glue solution not only can cause fluctuation of pressure in the cavity, but also can cause position deviation of the sensing optical fiber, so that an experimental result is completely invalid due to instability of boundary conditions. In summary, the existing monitoring device suffers from thermal strain interference generated by curing exotherm and is limited by boundary sealing bottleneck of low viscosity stage, and lacks a robust test system capable of realizing full period signal decoupling and adapting to various hardware configurations. Aiming at the problems, a curing shrinkage testing device for the component polymer packaging material is developed, and the device has profound industrial application value for establishing a digital prediction system from material molding to packaging failure by constructing a dynamic self-sealing environment and combining a multi-purpose compensation mechanism. Disclosure of Invention The invention aims to overcome the defects of the prior polymer curing shrinkage test technology that the traditional method (such as densitometry) only can measure the final shrinkage rate and can not observe the dynamic peak and evolution rule in the curing process in real time. Secondly, the glue solution leaks risk, the viscosity of the packaging material is extremely low in the initial curing stage, and the common die is easy to leak under the heating condition, so that spline defects or inaccurate volume metering are caused. Third, the deep coupling of temperature and strain, polymer curing is accompanied by intense exotherm, the center wavelength of the fiber is doubly modulated by temperature and shrinkage strain, and in the absence of high precision temperature compensation means, the test data is severely distorted. Fourth, the hardware dependence is high, and the prior art generally depends on a multichannel temperature monitor strongly, so that high-preci