JP2011103373A - Method and apparatus for evaluating releasability - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and apparatus for evaluating releasability in consideration of a release rate. <P>SOLUTION: When releasability is evaluated when an adherend is released from an adhesive sheet bonded to the adherend, an evaluation release rate used for evaluating releasability between the adherend and the adhesive sheet is calculated to evaluate releasability. For example, a release force is measured when the adhesive sheet is released at different release rates from a measurement member, which is bonded to the adhesive sheet, or the adherend, and an evaluation release rate is calculated based on the measured release force and the release rate in the measurement when the adherend is released from the adhesive sheet by a release apparatus different from that in the measurement. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a peelability evaluation method and a peelability evaluation apparatus for peeling off the adherend from an adhesive sheet affixed to the adherend.

  A semiconductor device manufacturing process includes a dicing process for separating a wafer into semiconductor elements in a state where an adhesive sheet is attached to a semiconductor wafer (hereinafter simply referred to as a wafer), and a separation device for separating the separated semiconductor elements. There are a pick-up process in which the semiconductor elements are separated and taken out one by one, and a die-bonding process in which the taken-out semiconductor elements are joined to a support member for mounting the semiconductor elements.

  Of these, the adhesive sheet used in the dicing step needs to have a characteristic that the semiconductor element can be held during dicing and the semiconductor element can be easily peeled off during pick-up. Conventionally, whether or not an adhesive sheet has these characteristics has been evaluated by measuring an actual peeling force in a peeling device used in a production line.

  On the other hand, in recent years, a simple evaluation method that does not use a peeling device for a production line is also known (for example, see Patent Document 1). In the evaluation method of Patent Document 1, the surface of the adhesive sheet opposite to the wafer application surface is pressed, and the indentation force when the semiconductor element is peeled is measured to evaluate the peelability at the time of pickup.

JP 2009-124120 A

  In all of the conventional peelability evaluation methods including those described in Patent Document 1, the peel strength at the time of peeling is determined, and the evaluation in consideration of the peeling speed has not been performed. However, since the success or failure of the peeling process is determined by whether or not the peeling is completed within a predetermined time, it is necessary to consider the peeling speed when evaluating the peelability.

  The objective of this invention is providing the peelability evaluation method and peelability evaluation apparatus which can consider peeling speed.

  In order to achieve the above object, the peelability evaluation method of the present invention is a peelability evaluation method for evaluating peelability when peeling the adherend from an adhesive sheet affixed to the adherend. It is characterized in that the peelability is evaluated by calculating a peel rate for evaluation used for evaluating the peelability between the adherend and the adhesive sheet.

  In the peelability evaluation method of the present invention, the peel force when the adhesive sheet is peeled off at a plurality of different peeling speeds from the measurement member to which the adhesive sheet is attached or the adherend is measured, and the measured peel Based on the force and the peeling speed at the time of measurement, it is preferable to calculate the peeling speed for evaluation when the adherend is peeled from the adhesive sheet by a peeling device different from that at the time of measurement.

  In the peelability evaluation method of the present invention, in calculating the peeling speed for evaluation, based on the measured peeling force, a fracture mechanics parameter at the time of peeling is calculated for each measured peeling force, and the measured peeling Based on a calculation model in which the calculated value of the fracture mechanics parameter is made to correspond to the peeling speed at the time of measurement via force and the state at the time of peeling at the other peeling device is modeled, the other peeling device The fracture mechanics parameter at the time of peeling at the time is calculated, based on the correspondence between the calculated value of the peeling speed and the fracture mechanics parameter at the time of measurement, and the calculation model at the time of peeling by the other peeling device It is preferable to calculate the peeling rate for evaluation using the calculated value of the fracture mechanics parameter.

  In the peelability evaluation method of the present invention, the fracture mechanics parameter at the time of peeling with the separate peeling device is calculated for each peeled area ratio that is a ratio of the peeled area to the sticking area, and the evaluation is performed for each peeled area ratio. It is preferable to calculate the peeling rate for evaluation, and set the minimum peeling rate for evaluation among the calculated peeling rates for evaluation as the final peeling rate for evaluation.

  In the peelability evaluation method of the present invention, the fracture mechanics parameter is preferably an energy release rate.

  In the peelability evaluation method of the present invention, each calculated value is preferably calculated by finite element analysis.

  In the peelability evaluation method of the present invention, the adherend is a semiconductor element in which the semiconductor wafer is diced in a state where the semiconductor wafer is adhered to the adhesive sheet, and the peelability evaluation method is performed on the adhesive sheet. It is preferable that the semiconductor element is applied when the semiconductor element is peeled from the adhesive sheet by pushing up the surface of the semiconductor element opposite to the sticking surface with a needle tip.

  On the other hand, the peelability evaluation apparatus of the present invention is a peelability evaluation apparatus for peeling off the adherend from an adhesive sheet attached to an adherend, wherein the measurement member to which the adhesive sheet is attached or the Data acquisition means for acquiring a peeling force measured by peeling the adhesive sheet from the adherend at a plurality of different peeling speeds, and a fracture mechanics at the time of peeling for each measured peeling force based on the measured peeling force A parameter calculation unit for measurement that calculates a parameter, a parameter association unit for measurement that associates the calculated value of the fracture mechanics parameter with the peeling speed at the time of measurement via the measured peeling force, and the separate peeling A model-corresponding parameter calculating means for calculating the fracture mechanics parameter at the time of peeling with the other peeling device, based on an arithmetic model that models the state at the time of peeling with the device; Using the correspondence relationship between the calculated values of the peeling speed and the fracture mechanics parameter at the time of measurement and the calculated value of the fracture mechanics parameter based on the calculation model at the time of peeling with the other peeling device, A peeling rate calculating means for calculating an evaluation peeling rate used for evaluation of the property.

  Further, the peelability evaluation apparatus of the present invention is a peelability evaluation apparatus for peeling the adherend from the adhesive sheet affixed to the adherend, wherein the measurement member to which the adhesive sheet is affixed or the A peeling force measuring device that peels off the adhesive sheet from the adherend at a plurality of different peeling speeds, and measures a peeling force at the time of peeling, and a data acquisition unit that acquires the measured peeling force in the peeling force measuring device; Based on the measured peeling force, a measurement parameter calculation means for calculating a fracture mechanics parameter at the time of peeling for each measured peeling force, and the peeling speed at the time of measurement via the measured peeling force. Based on the calculation parameter modeling unit that associates the calculated value of the fracture mechanics parameter with the measurement-time parameter associating unit and the state at the time of peeling with the separate peeling device, the separate peeling Model-corresponding parameter calculating means for calculating the fracture mechanics parameter at the time of peeling at a position; a correspondence relationship between the peeling speed at the time of measurement and the calculated value of the fracture mechanics parameter; and peeling by the separate peeling device And a peeling rate calculation means for calculating an evaluation peeling rate used for the evaluation of the peelability using the calculated value of the fracture mechanics parameter based on the calculation model of the time.

  In the peelability evaluation apparatus of the present invention, the model corresponding parameter calculation means calculates the fracture mechanics parameter at the time of peeling with the separate peeling apparatus for each peeling area ratio that is a ratio of the peeling area to the sticking area, The peeling rate calculation means calculates the peeling rate for evaluation for each peeling area ratio, and sets the minimum peeling rate for evaluation among the calculated peeling rates for evaluation as the final peeling rate for evaluation. It is preferable.

  According to the present invention as described above, the peeling rate for evaluation used for the evaluation of the peelability between the adherend and the adhesive sheet is calculated, so that the peel rate can be taken into account in the peelability evaluation. Therefore, in the peeling process, it can be determined whether or not the peeling is completed within a predetermined time.

  Further, the evaluation peeling speed when peeling the adherend from the adhesive sheet with a peeling device different from the measurement time is calculated based on the measured peeling force and the peeling speed at the time of measurement. In calculating the peeling speed, it is only necessary to perform simple peeling force measurement using a measuring peeling device. Therefore, it is not necessary to perform a peeling test with an actual peeling apparatus, and the peeling force can be evaluated efficiently.

  Furthermore, since the measurement results obtained by the measuring peeling device are highly versatile, the peeling force measured by peeling with the measuring peeling device regardless of the type of the actual peeling device is measured by the evaluation peeling speed. It can be used for calculation. Therefore, a peelability evaluation method having versatility can be obtained.

  In calculating the peeling speed for evaluation in the present invention, the calculated value of the fracture mechanics parameter is made to correspond to the peeling speed at the time of measurement through the measured peeling force, and the state at the time of peeling with an actual peeling apparatus is modeled. Based on the calculated calculation model, the fracture mechanics parameter at the time of peeling with the other peeling device is calculated, the correspondence between the peeling speed at the time of measurement and the calculated value of the fracture mechanics parameter, and the other peeling device with If the evaluation peeling speed is calculated using the calculated value of the fracture mechanics parameter based on the calculation model at the time of peeling, a highly accurate peeling speed for evaluation can be calculated.

  That is, the fracture mechanics parameter is a physical quantity indicating the state of the end portion of the peeling interface, and does not depend on the state of other parts of the adhesive sheet and the adherend or the type of the peeling device. Therefore, by calculating the peel rate for evaluation via the fracture mechanics parameter, it is possible to eliminate as much as possible various effects in the process of calculating the peel rate for evaluation from the peel force measurement value and the peel rate at the time of peel force measurement. Therefore, the peeling rate for evaluation can be calculated with high accuracy.

  Further, in calculating the peeling rate in the present invention, the fracture mechanics parameter at the time of peeling with an actual peeling device is calculated for each peeling area ratio that is the ratio of the peeling area to the application area, and the peeling for evaluation is performed for each peeling area ratio. If the speed is calculated and the minimum evaluation peeling speed is calculated as the final evaluation peeling speed, the peelability will be evaluated at the most severe evaluation peeling speed. Sexual evaluation can be reliably performed.

  Further, in calculating the peeling speed for evaluation in the present invention, if the peeling speed is calculated by finite element analysis, the material characteristics of the adhesive sheet and the adherend and the characteristics of the peeled state may be nonlinear, or the peeling device Even in a situation where it is difficult to calculate the peeling speed using a general equation, as in the case where the mechanism is complicated, the peeling speed for evaluation can be easily calculated without requiring a complicated procedure. Therefore, the versatility and efficiency of peel force evaluation can be improved.

The figure for demonstrating the dicing process of the wafer which concerns on 1st Embodiment of this invention. The figure for demonstrating the pick-up process of the wafer which concerns on the said 1st Embodiment. The side view which shows the peeling force measuring apparatus which concerns on the said 1st Embodiment. The perspective view which shows the holding | maintenance apparatus of the peeling force measuring apparatus which concerns on the said 1st Embodiment. The perspective view which shows the tension | pulling apparatus of the peeling force measuring apparatus which concerns on the said 1st Embodiment. The block diagram which shows the structure of the peelability evaluation apparatus which concerns on 2nd Embodiment of this invention. The flowchart for demonstrating the effect | action of the peelability evaluation apparatus which concerns on the said 2nd Embodiment. The figure which shows the relationship between peeling speed and peeling force. The figure which shows the relationship between the peeling force and the calculated value of an energy release rate. The figure which shows the relationship between the peeling speed and the calculated value of an energy release rate. The figure which shows the relationship between a peeling area rate and an energy release rate. The figure which shows the relationship between peeling area ratio and peeling speed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the second embodiment to be described later, the same components as those of the first embodiment described below are denoted by the same reference numerals as those of the first embodiment, and the description thereof is omitted or simplified.

[First Embodiment]
This embodiment demonstrates the peelability evaluation method when peeling a to-be-adhered body from the adhesive sheet affixed on the to-be-adhered body. Specifically, an application example in the case where a semiconductor element obtained by dicing a wafer is peeled from an adhesive sheet attached to a wafer as an adherend in a pick-up process of a semiconductor device will be described.

First, a semiconductor element peeling method in the pick-up process will be described.
As shown in FIG. 1, the wafer W is diced in a state of being attached to the adhesive sheet S in a dicing process that is a pre-process of the pickup process, and is singulated into semiconductor elements D. Here, as the adhesive sheet S, a dicing / die-bonding sheet having a wafer fixing function and a die bonding function is used. The dicing / die-bonding sheet is a sheet in which an adhesive layer S2 is laminated on one surface of the base material sheet S1, and when the semiconductor element D is peeled off, the adhesive layer S2 is separated from the base material sheet S1 together with the semiconductor element D. Peel off.

  As shown in FIG. 2A and FIG. 2B, after the wafer W is diced into the semiconductor element D in the dicing process, in the pick-up process, a peeling apparatus different from the one used at the time of measuring the peeling force described later. 10 is peeled off. The peeling apparatus 10 includes a steel holder 11 and a pedestal 13 to which a needle 12 is attached and accommodated inside the holder 11.

  In the pickup process, the wafer W is attracted and fixed onto the holder 11. While the wafer W is attracted and fixed on the holder 11, the pedestal 13 in the holder 11 is raised, so that the needle 12 passes through the hole in the surface of the holder 11, and the attachment surface of the wafer W of the base sheet S1 Push up the opposite side. Thereby, the semiconductor element D is peeled from the base material sheet S1 together with the adhesive layer S2.

In the evaluation of the peelability of the semiconductor element D in such a pickup process, the calculated peeling speed for evaluation is used. In this embodiment, the peeling rate for evaluation is calculated through the following steps (A) to (E).
(A) Step for obtaining the relationship between the peeling speed and the peeling force of the adhesive sheet S by the peeling force measurement described later (B) Step for obtaining the relationship between the peeling force and the fracture mechanics parameter at the time of peeling force measurement (C) Step (A ) A step for obtaining the relationship between the peeling speed and the fracture mechanics parameter from the result of (B) (D) A step for obtaining the relationship between the peel area ratio and the fracture mechanics parameter (E) For evaluation from the results of the steps (C) and (D) Process for obtaining peeling speed

Hereinafter, each step will be described in detail.
(A) The process of calculating | requiring the relationship between the peeling speed and peeling force of the adhesive sheet S by peeling force measurement As shown in FIG. The peeling force when it was made to measure is measured, and the relationship between the peeling speed of the adhesive sheet S and the peeling force is obtained. For the measurement member M, for example, a glass plate is used. The peeling force of the adhesive sheet S from the wafer W may be measured by using the wafer W instead of the measurement member M.

  If the adhesive sheet S is a dicing / die-bonding sheet, the adhesive layer S2 is peeled off together with the semiconductor element D in the pick-up step, and therefore the peeling interface is between the adhesive layer S2 and the base sheet S1. On the other hand, if the adhesive sheet S is a conventional dicing tape, the peeling interface is between the measurement member M and the adhesive layer S2.

  In any case of the adhesive sheet S, in order to obtain a stable numerical value in the peeling force measurement, the peeling angle θ formed by the sticking surface of the measurement member M and the pulling direction Y of the pulling device 3 can be kept constant. desirable. For this reason, in measuring the peeling force, for example, it is desirable to use a peeling force measuring device 1 that can move the measurement member M side at the same speed as the base sheet S1 side as shown in FIG.

  In FIG. 3, the peeling force measuring device 1 is a device that measures the peeling force of the adhesive sheet S, and includes a holding device 2 and a tension device 3. Note that overall control of the peeling force measuring apparatus 1 is performed by a control unit (not shown).

As shown in FIG. 4, the holding device 2 includes a base 21, a shaft motor 22, a mounting member 23, a linear encoder mounting base 24, a linear encoder 25, and a guide rail 26.
The base 21 is a table for fixing the shaft motor 22. At both ends of the base 21, mounting bases 21A are provided, and shaft motors 22 are attached to the mounting bases 21A.

  The shaft motor 22 which is a linear motion motor includes a shaft 22A whose both ends are fixed to the mounting base 21A, and a slider 22B which is movably provided along the shaft 22A. Although not shown, the shaft 22A is provided with a magnet, and the slider 22B is provided with a coil. By applying a current to the coil of the slider 22B, electromagnetic force is applied to the slider 22B, and the slider 22B moves. .

  The attachment member 23 is attached to the slider 22B of the shaft motor 22, and is configured to reciprocate on the base 21 together with the slider 22B. At the time of measuring the peeling force, the measurement piece P in a state where the adhesive sheet S is attached to the measurement member M is attached and held on the attachment member 23. A linear encoder mounting base 24 is attached to such an attachment member 23.

  The linear encoder 25 includes a linear scale 25A that is attached to the base 21 and records magnetically or optically readable position information, and a detection head 25B that is attached to the linear encoder mounting base 24 and reads the linear scale 25A. ing. A signal from the detection head 25B is sent to a control unit (not shown).

  The guide rail 26 extends on the base 21 in parallel with the shaft 22 </ b> A of the shaft motor 22. The guide rail 26 engages with a guide groove (not shown) of the linear encoder mounting base 24 that moves together with the slider 22B, thereby restricting the movement of the slider 22B to a reciprocating motion along the axial direction of the shaft 22A.

  As shown in FIG. 5, the tension device 3 includes a clamping unit 31, a peeling angle adjusting unit 32 that rotatably supports the clamping unit 31 with respect to the attachment member 23, and a measuring unit that measures the peeling force of the adhesive sheet S. Except for 33, the holding device 2 has the same structure. For this reason, only a difference from the holding device 2 will be described here, and the same components will be denoted by the same reference numerals and detailed description thereof will be omitted.

The clamping unit 31 is configured to be able to clamp the adhesive sheet S. As such a clamping part 31, a crocodile clip is mentioned, for example.
The peeling angle adjusting unit 32 is rotatably provided on the mounting member 23 by a rotating shaft (not shown) supported by a bearing or the like. The peeling angle adjusting unit 32 is configured to be rotatable in both clockwise and counterclockwise directions, and is configured to be able to arbitrarily set the peeling angle θ (see FIG. 3).

  The measurement unit 33 includes a force sensor that is connected to the clamping unit 31 and can measure the tensile load of the clamping unit 31. The measuring unit 33 converts the detected force value into an electric signal as a peeling force, and outputs the electric signal to the outside or a display unit (not shown).

  In the peeling force measuring apparatus 1 as described above, as shown in FIG. 3, after attaching the measurement piece P with the adhesive sheet S affixed to the measurement member M to the attachment member 23, only the base sheet S <b> 1 or The slider 22B of each shaft motor 22 in the holding device 2 and the tensioning device 3 is moved in a state where the base sheet S1 and the adhesive layer S2 are sandwiched between the clamping portions 31 of the tensioning device 3. Then, since a tensile load acts on the clamping part 31, the peeling force of the adhesive sheet S can be measured by measuring the force at this time with the measuring part 33.

  Moreover, in the peeling force measuring apparatus 1, the slider 22B of each shaft motor 22 in the holding | maintenance apparatus 2 and the tension | pulling apparatus 3 can be moved at the same speed. For this reason, the peeling force of the adhesive sheet S can be measured while keeping the peeling angle θ of the adhesive sheet S constant. Such operation control of each slider 22 </ b> B is performed based on a signal from the linear encoder 25 by a control unit electrically connected to both the holding device 2 and the tension device 3.

  In such a peeling force measuring apparatus 1, the speed at which both the sliders 22B of the holding device 2 and the tensioning device 3 are moved at the same speed can be arbitrarily set. For this reason, since the peeling force of the adhesive sheet S can be measured by changing the peeling speed, the relationship between the peeling speed and the peeling force can be obtained. When the slider 22B of the holding device 2 and the tension device 3 is moved at the same speed in the peeling force measuring device 1, the peeling speed of the adhesive sheet S is the moving speed of both sliders 22B of the holding device 2 and the tension device 3. It becomes.

(B) The process of calculating | requiring the relationship between the peeling force at the time of peeling force measurement, and a fracture mechanics parameter In this process, the relationship between the peeling force at the time of peeling force measurement and a fracture mechanics parameter is calculated | required. Fracture mechanics parameters include energy release rate, stress intensity factor, crack tip opening displacement, and the like. The calculation model at this time conforms to the peel force measurement in step (A) described above. That is, the calculation model used in this process is a model of the measurement state at the time of peel force measurement, such as the mechanism of the peel force measuring apparatus 1 shown in FIGS. 3 to 5 and the characteristics and dimensions of the adhesive sheet S. As the peeling force applied to this calculation model, the peeling force obtained by measurement in the step (A) is used.

  As a calculation method, for example, a method by finite element analysis can be mentioned. The analysis is preferably a linear elastic analysis from the viewpoint of simplicity, and the characteristic values used for the analysis include the Young's modulus and Poisson's ratio of the base sheet S1 and the adhesive layer S2 in the adhesive sheet S. As such an analysis method, there is a two-dimensional analysis of plane strain.

(C) The process of calculating | requiring the relationship between a peeling rate and a fracture mechanics parameter from the result of process (A) (B) In this process, from the result of process (A) and (B) mentioned above, the peeling speed of adhesive sheet S and Find the relationship with fracture mechanics parameters. For example, in the step (A), the value of the peeling force β [N / 25 mm] is obtained at the peeling speed α [mm / sec], and in the step (B), the energy release rate γ [MPa] at the peeling force β [N / 25 mm]. Suppose that the value of mm] is obtained. In that case, since the value of the peeling force is the same in both cases, the energy release rate can be derived as γ [MPa · mm] at the peeling speed α [mm / sec].

(D) The process of calculating | requiring the relationship between a peeling area rate and a fracture mechanics parameter In this process, the relationship between a peeling area rate and a fracture mechanics parameter is calculated | required by calculation. Here, the peeled area ratio refers to the ratio of the area of the peeled portion of the pasted area. The calculation model at this time conforms to the actual mechanism of the peeling apparatus 10. That is, the calculation model used in this process is a model of the state at the time of peeling in the actual pickup process, such as the mechanism of the peeling device 10, the characteristics and dimensions of the wafer W, the characteristics and dimensions of the adhesive sheet S, The arrangement of the needles 12 on the pedestal 13 accommodated in the holder 11 shown in FIGS. 2A and 2B, the amount of protrusion of the needles 12, and the like are also taken into consideration.

  As a calculation method, for example, a method by finite element analysis can be mentioned. Linear elasticity analysis is desirable from the viewpoint of simplicity, and the characteristic values used for the analysis include Young's modulus and Poisson's ratio of the base material sheet S1 and the adhesive layer S2 in the adhesive sheet S. If the model shape is not suitable for two-dimensional approximation, it is desirable to perform analysis in three dimensions. In addition, the deformation | transformation given to base material sheet S1 with the needle | hook 12 etc. may give displacement directly to base material sheet | seat S1, without modeling jigs, such as the needle 12.

(E) The process of calculating | requiring the peeling speed for evaluation from the result of process (C) and (D) In this process, the peeling speed for evaluation is calculated | required from the result of the process of process (C) and (D) mentioned above. As a method in that case, the idea of the step (C) can be used. Specifically, from the relationship between the peel rate and fracture mechanics parameter obtained in step (C) and the relationship between the peel area rate and fracture mechanics parameter obtained in step (D), the peel rate and peel area rate. Seeking relationship with. In the present embodiment, a minimum evaluation peeling rate is selected from the evaluation peeling rates obtained for each peeling area ratio, and is set as a final evaluation peeling rate.

  The peelability in the pick-up process can be evaluated using the peel rate for evaluation calculated as described above. That is, like the result of the Example mentioned later, when the calculated peeling speed for evaluation is high, the peeling speed in the actual peeling apparatus 10 is also high, and it has excellent peelability. Therefore, for example, if the value of the peeling speed per semiconductor element D required in the actual pick-up process is set in advance, and the calculated value of the peeling speed for evaluation falls below the set value, the pick-up process can be successful. It can be judged that it has a degree of peelability. In addition, for example, by changing the position of the needle 12 and the height of the push-up in the pick-up process to calculate the peeling speed for evaluation, by comparing these peeling speeds for evaluation and selecting the condition with the highest peeling speed for evaluation, Optimal peeling conditions can be set.

[Second Embodiment]
In the present embodiment, a peelability evaluation method using the peelability evaluation apparatus 4 shown in FIG. 6 will be described. As an example, an application example in the case where the semiconductor element D is peeled from the adhesive sheet S in the pick-up process of the semiconductor device will be described as in the first embodiment.

In FIG. 6, the peelability evaluation apparatus 4 includes an operation unit 41, a storage unit 42, a data acquisition unit 43, an arithmetic processing unit 44, and an output unit 45.
The operation means 41 is a part for operating the peelability evaluation apparatus 4. Examples of the operation unit 41 include a keyboard and a touch panel. The peel speed and peel force when measuring the peel force of the adhesive sheet S in the peel force measuring apparatus 1 described above are input to the peelability evaluation apparatus 4 through the operation of the operation means 41.

  The storage means 42 is configured as a storage device such as a memory or a hard disk. The storage means 42 stores various programs executed by the arithmetic processing means 44 and various parameters necessary for executing the programs.

  The data acquisition unit 43 acquires data and commands necessary for arithmetic processing in the arithmetic processing unit 44 such as data and commands input by the operation unit 41 and data stored in the storage unit 42. Further, the data acquisition means 43 is electrically connected to the external terminal 46 and can directly acquire external data such as a peeling force and a peeling speed output from the peeling force measuring device 1. The peeling speed and peeling force at the time of peeling force measurement input from the operation means 41 and the external terminal 46 are acquired by the data acquisition means 43 and sent to the arithmetic processing means 44.

  The arithmetic processing means 44 is composed of a CPU (Central Processing Unit) or the like and performs various arithmetic processes. The arithmetic processing means 44 includes a measurement time parameter calculation means 44A, a measurement time parameter association means 44B, a model corresponding parameter calculation means 44C, and a peeling speed calculation means 44D.

  The measurement parameter calculation unit 44A calculates a fracture mechanics parameter at the time of peeling for each measured peeling force based on the peeling force acquired by the data acquisition unit 43. The fracture mechanics parameter calculated by the measurement parameter calculation unit 44A is sent to the measurement parameter association unit 44B.

  The measurement time parameter association means 44B associates the calculated value of the fracture mechanics parameter with the peel speed in association with the measured peel force. The peeling speed at the time of peeling force measurement and the calculated value of the fracture mechanics parameter associated by the measurement time parameter association means 44B are sent to the peeling speed calculation means 44D.

  The model corresponding parameter calculation unit 44C calculates a fracture mechanics parameter when the semiconductor device D is peeled from the adhesive sheet S by the peeling device 10 using an arithmetic model corresponding to the peeling operation in the peeling device 10. The fracture mechanics parameter calculated by the model corresponding parameter calculation unit 44C is sent to the peeling speed calculation unit 44D.

  The peeling speed calculating means 44D uses the correspondence between the peeling speed and the calculated value of the fracture mechanics parameter and the calculated value of the fracture mechanics parameter based on the calculation model of the peeling apparatus 10 to perform peeling for evaluation when the peeling apparatus 10 performs peeling. Calculate the speed. The evaluation peeling speed calculated by the peeling speed calculating means 44D is sent to the output means 45.

  The output unit 45 is configured to be able to display the operating state of the peelability evaluation device 4 including the operation state of the operation unit 41 and the calculation processing result of the calculation processing unit 44. Examples of the output means 45 include a display and a printer.

Next, the operation of the peelability evaluation apparatus 4 will be described based on the flowchart shown in FIG.
First, the data acquisition means 43 of the peelability evaluation apparatus 4 acquires the peel speed and peel force at the time of peel force measurement (step ST1). The data acquisition unit 43 stores the acquired peeling speed and peeling force in the storage unit 42 in association with each other.

  Next, the measurement parameter calculation unit 44A calculates a fracture mechanics parameter corresponding to the peeling speed at the time of peeling force measurement based on the peeling force acquired by the data acquisition unit 43 (step ST2). That is, the measurement parameter calculation unit 44A gives the measured peeling force to the calculation model corresponding to the peeling operation in the peeling force measuring apparatus 1, and calculates the fracture mechanics parameter at the time of peeling force measurement. The measurement parameter calculation unit 44A stores the measured peeling force and the calculated fracture mechanics parameter in the storage unit 42 in association with each other.

  Subsequently, the measurement-time parameter associating means 44B associates the calculated value of the fracture mechanics parameter with the peeling speed in association with the peeling speed through the measured peeling force (step ST3). Specifically, the measurement time parameter association means 44B associates the peel speed associated with the common peel force with the calculated value of the fracture mechanics parameter from the stored values of the storage means 42, and stores the storage means 42. Remember me.

  At this time, the measurement parameter associating unit 44B calculates a correspondence relation between the peeling speed and the calculated value of the fracture mechanics parameter from the related peeling speed and the calculated value of the fracture mechanics parameter by, for example, the least square method. Ask. This corresponding relational expression is used for calculation of the peeling speed in the peeling speed calculation means 44D.

  After step ST3, the model corresponding parameter calculation unit 44C calculates a fracture mechanics parameter when the semiconductor device D is peeled from the adhesive sheet S by the peeling device 10 using the calculation model of the peeling device 10 (step ST4). That is, the model-corresponding parameter calculation unit 44C sets conditions when the peeling device 10 is made to peel the calculation model corresponding to the peeling operation in the peeling device 10 such as the thickness of the wafer W and the push-up height of the needle 12. Given, the fracture mechanics parameter at the time of peeling with the peeling device 10 is calculated for each peeling area ratio. Further, the model corresponding parameter calculation unit 44C stores the peeling area ratio and the calculated fracture mechanics parameter in the storage unit 42 in association with each other.

  The peeling speed calculation means 44D calculates the peeling speed for evaluation when the semiconductor device D is peeled from the adhesive sheet S by the peeling device 10 (step ST5). Specifically, the peeling speed calculation unit 44D includes the correspondence between the peeling speed and the calculated value of the fracture mechanics parameter obtained by the measurement parameter association unit 44B, and the peeling device 10 obtained by the model correspondence parameter calculation unit 44C. Using the calculated value of the fracture mechanics parameter at the time of peeling based on the calculation model, the peeling speed for evaluation in the peeling apparatus 10 is calculated for each peeling area ratio.

  That is, the peeling speed calculation means 44D substitutes the calculated value of the fracture mechanics parameter based on the calculation model of the peeling apparatus 10 into the corresponding relationship between the calculated value of the peeling speed and the fracture mechanics parameter obtained by the parameter association means 44B during measurement. And the peeling rate for evaluation is calculated for every peeling area ratio. In the present embodiment, the minimum evaluation peeling speed is set as the final evaluation peeling speed among the evaluation peeling speeds obtained for each peeling area ratio.

The arithmetic processing means 44 outputs the evaluation peeling speed calculated in this way to the output means 45 (step ST6).
Even when the above peelability evaluation apparatus 4 is used, the peelability in the pick-up process can be evaluated using the evaluation peel rate output to the output means 45 as in the first embodiment.

  Hereinafter, examples evaluated by the above-described peelability evaluation method will be shown. In the following example, the base sheet S1 of the adhesive sheet S has a surface tension of 35 [mN / m], a Young's modulus of 140 [MPa], a Poisson's ratio of 0.45, and the adhesive layer S2 is The dry film thickness is 20 μm, 23 [° C.], Young's modulus is 30 [MPa], and Poisson's ratio is 0.4. As the wafer W, a silicon wafer having a diameter of 150 [mm], a Young's modulus of 190000 [MPa], and a Poisson's ratio of 0.28 was used.

Regarding the step (A), in the peel force measurement, the peel force of the adhesive sheet S having a width of 25 [mm] × 100 [mm] was measured with the peel force measuring device 1 shown in FIGS. First, the adhesive sheet S is affixed to the wafer W at 23 [° C.], and ultraviolet rays are 350 [mW / cm ² ], 190 [from the base sheet S1 side using an ultraviolet irradiation apparatus (Adwill RAD2000, manufactured by Lintec Corporation). mJ / cm ² ].

  Thereafter, in the peeling force measuring device 1, the entire surface of the wafer W was fixed to the mounting member 23 of the holding device 2 with double-sided tape. Subsequently, a test for peeling the base sheet S1 from the laminated body of the wafer W and the adhesive layer S2 by holding the base sheet S1 on the holding part 31 of the tensioning device 3 is performed by the slider 22B of the holding device 2 and the tensioning device 3. The speed of was changed. The peeling angle θ at this time was 90 degrees. FIG. 8 shows the relationship between the peeling speed and the peeling force obtained by such a test.

  For step (B), finite element analysis software ABAQUS STANDARD (version 6.7-1) was used. Moreover, the analysis performed the linear elasticity analysis in two dimensions. As the element, a four-node square plane strain element was used. In the analysis, the total length of the adhesive sheet S was set to 60 [mm], and the peeled length was set to 20 [mm]. As material constants, Young's modulus and Poisson's ratio of each member were used. The energy release rate was used as the fracture mechanics parameter, and the calculation method incorporated in the analysis software was used to calculate the energy release rate. In this analysis, the peel force obtained by the measurement in the step (A) was given, and the energy release rate was calculated. FIG. 9 shows the relationship between the peeling force and the energy release rate obtained in the step (B).

  In the step (C), the relationship between the peeling speed of the adhesive sheet S and the energy release rate was obtained from the results of the steps (A) and (B). That is, the energy release rate corresponding to the peel rate was obtained from the peel rate and the energy release rate having the same peel force value. The relationship between the peeling rate and energy release rate obtained in step (C) is shown in FIG.

  In FIG. 10, the energy release rate is a substantially constant value in a region where the peeling speed is a certain value or less, and it is considered that the peeling hardly progresses below this energy release rate. On the other hand, since the logarithm of the peeling speed and the energy release rate tended to be proportional in the area where the peeling speed was the above value or more, the relationship between the peeling speed and the energy release rate was minimized in the area where the peeling speed was the value or more. It was defined by the following formula 1 approximated by the square method. G is an energy release rate, V is a peeling speed, and C1 and C2 are constants.

[Formula 1]
G = C1 × Log (V) + C2 (1)

  For step (D), the same finite element analysis software ABAQUS STANDARD (version 6.7-1) as in step (B) was used. In addition, the shape elasticity analysis was performed in three dimensions, and an 8-node hexahedral element was used as the element. The size of the semiconductor element D is 10 [mm] × 10 [mm], and 0.6 [MPa] is set as the pressure at which the base sheet S1 is adsorbed to the holder 11 accommodating the pedestal 13 to which the needle 12 is attached. To give.

  Also, four pins of the needle 12 are provided at four positions (8 [mm] × 8 [mm]), and a displacement corresponding to the protruding amount of the needle 12 is given. Peeling due to the needle 12 being pushed up occurs concentrically around the needle 12, and an area with a peeled area ratio of 50 to 100 [%] was evaluated. The energy release rate was calculated using a method incorporated in the analysis software. FIG. 11 shows the relationship between the peeled area rate and the energy release rate obtained in the step (D).

  In the step (E), the relationship between the peel area ratio and the peel speed in the pickup step was determined from the results of the steps (C) and (D). That is, after substituting the value of the energy release rate corresponding to the peel area ratio obtained in the step (C) into the above formula (1), the formula (1) is modified to evaluate the peel for evaluation corresponding to the peel area ratio. The speed value was calculated. FIG. 12 shows the relationship between the peel area ratio and peel speed obtained in the step (E). Thus, the minimum evaluation peeling speed was determined as the final evaluation peeling speed in the pickup process from the evaluation peeling speed obtained for each peeling area ratio.

  In FIG. 12, when paying attention to the minimum peeling speed for each condition in the pick-up process, the peeling speed is 200 [μm] /0.25 [mm], 300 [μm] of the thickness of the semiconductor element D / needle push-up displacement. /0.35 [mm] and 200 [μm] /0.15 [mm] in this order. Therefore, it is considered that peeling is completed in this order in the pickup process. Thus, by obtaining the separation / separation speed at the time of pickup by the above steps (A) to (E), the peelability of the adhesive sheet S can be evaluated and the pickup performance of the semiconductor element D can be estimated.

  Hereinafter, in order to verify the validity of this evaluation, the result of the pick-up suitability of the semiconductor element D performed using a peeling apparatus in an actual semiconductor manufacturing process will be described.

The adhesive sheet S was attached to the polished surface of the wafer W at 23 [° C.] with a tape mounter (manufactured by Lintec, Adwill RAD 2500), and fixed to the ring frame for wafer dicing. Thereafter, ultraviolet rays were irradiated from the base sheet S1 side at 350 [mW / cm ² ] and 190 [mJ / cm ² ] using an ultraviolet irradiation device (manufactured by Lintec, Adwill RAD2000).

  Next, dicing was performed to the size of the semiconductor element D of 10 [mm] × 10 [mm] using a dicing apparatus (DFD651, manufactured by DISCO Corporation). The amount of cut during dicing was such that the substrate was cut by 20 [μm]. Next, by using a 4-pin die bonder (BESTEM-D02 manufactured by Canon Machinery) as shown in FIG. 2, the semiconductor element D is pushed up to a different push-up height at a push-up speed of 1.0 [mm / sec]. The time required for complete peeling was determined. The thickness of the wafer W and the push-up height of the needle 12 are shown in Table 1 below.

  Table 2 shows the evaluation results of the wafer W under the above test conditions.

  From Table 2, it can be seen that when the calculated value of the peeling rate for evaluation is large, the peeling time at the time of actual pickup becomes small, and thus the peeling rate at the time of pickup is high. That is, the peeling speed for evaluation obtained by the evaluation method of the embodiment shows the same tendency as the peelability in an actual peeling apparatus.

  Furthermore, when only the push-up speed of the needle 12 is changed to 10 [mm / sec] with respect to the above test conditions, when 25 semiconductor elements D are pushed up, the semiconductor element D cannot be picked up and the apparatus stops. Table 3 shows the results of the number of times obtained. The number of successful pickups / total number of test inputs in Table 3 is the total number of successful pickups of the semiconductor elements D picked up within a predetermined time by the die bonder without cracks occurring in the semiconductor elements D / total number of test inputs. The number.

  As can be seen from Table 3, when the peeling speed for evaluation is high, the pick-up success is high, and the time required for pick-up is within the time required in the pick-up process. It can be seen that the peeling rate for evaluation during the pick-up process obtained in (1) shows the same tendency as the pick-up suitability in the actual production test.

  As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described with particular reference to certain specific embodiments, but without departing from the spirit and scope of the invention, Various modifications can be made by those skilled in the art in terms of material, quantity, and other detailed configurations. In addition, the description of the shape, material, and the like disclosed above is exemplary for ease of understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

  For example, in each of the above embodiments, the case where the adherend is the wafer W has been shown. However, the adherend is not limited to the wafer W, and other plates such as a glass plate, a steel plate, or a resin plate are used. A member other than a plate-like member or the like can also be targeted. Examples of the wafer W include a silicon wafer and a compound wafer. And the adhesive sheet stuck to such a to-be-adhered body is not restricted to the adhesive sheet S shown in the above embodiment, but can be any protective sheet, any other sheet, film, tape, etc. Adhesive sheets with applications and shapes can be applied.

  In each of the above embodiments, a dicing / die bonding sheet having a wafer fixing function and a die bonding function is used as the adhesive sheet S, and the semiconductor element D is peeled from the base material sheet S1 together with the adhesive layer S2. Not limited to. In short, the adhesive sheet S may be an adhesive sheet S in which an adhesive layer S2 is laminated on one surface of the base sheet S1, and the adherend is peeled off from the base sheet S1 together with the adhesive layer S2. However, only the adherend may be peeled from the adhesive layer S2 while the adhesive layer S2 is adhered to the base sheet S1.

  In each of the above-described embodiments, the correspondence relationship obtained by the least square method is used as the correspondence relationship between the peeling speed and the calculated value of the fracture mechanics parameter. However, the correspondence relationship is not limited to this, and the correspondence relationship between the two is not necessarily expressed in the form of an equation. There is no need to represent it. In short, it is only necessary to know the calculated values of the peeling speed and the fracture mechanics parameter corresponding to each other. For example, by performing an interpolation operation between the adjacent peeling speeds and the calculated values of the adjacent fracture mechanics parameters, The peeling rate corresponding to the calculated value of the fracture mechanics parameter based on the calculation model can be calculated.

  In each of the above embodiments, the energy release rate is used as the fracture mechanics parameter, but the present invention is not limited to this. In short, the fracture mechanics parameter is a parameter that can indicate the state of the end portion of the peeling interface of the adhesive sheet S without depending on the state of the adhesive sheet and other parts of the adherend and the type of the peeling device. For example, a stress intensity factor or crack tip opening displacement may be used.

  In each of the above embodiments, the peeling force measurement apparatus 1 as shown in FIGS. 3 to 5 was used for the peeling force measurement, but any other value can be used as long as a stable numerical value can be obtained in the peeling force measurement. An apparatus may be used.

  For example, the peeling force measuring apparatus 1 includes the clamping unit 31 and the adhesive sheet S is clamped by the clamping unit 31, but is not limited thereto. In short, it is only necessary that the adhesive sheet S can be held in measuring the peeling force. For example, a holding part may be provided instead of the sandwiching part 31, and the adhesive sheet S may be adsorbed or adhered to the holding part.

  Moreover, in the peeling force measuring apparatus 1, although the shaft motor 22 was used, it is not restricted to this. In short, in order to keep the peeling angle θ of the adhesive sheet S constant, each slider 22B of the holding device 2 and the tension device 3 may be moved at the same speed, and for example, a ball screw or the like may be used.

  In the second embodiment, the data acquisition unit 43 of the peelability evaluation apparatus 4 has acquired the peeling speed and the peeling force at the time of the peeling force measurement input by the operation unit 41, but is not limited thereto. You may make it acquire the peeling speed and peeling force at the time of peeling force measurement directly from the peeling force measuring apparatus 1. FIG. That is, the peelability evaluation device 4 may be configured to include the peel force measurement device 1, and the data acquisition unit 43 may directly acquire the peel speed and the peel force from the peel force measurement device 1.

DESCRIPTION OF SYMBOLS 1 Peeling force measuring device 2 Holding device 3 Pulling device 4 Peelability evaluation device 41 Operation means 42 Storage means 43 Data acquisition means 44 Operation processing means 44A Measurement parameter calculation means 44B Measurement parameter association means 44C Model correspondence parameter calculation means 44D Peeling speed calculation means 45 Output means 10 Peeling device S Adhesive sheet S1 Substrate sheet S2 Adhesive layer W Wafer M Measuring member θ Peeling angle

Claims (10)

A peelability evaluation method for evaluating peelability when peeling the adherend from an adhesive sheet affixed to an adherend,
A peelability evaluation method, wherein the peelability is evaluated by calculating a peel rate for evaluation used for evaluating the peelability between the adherend and the adhesive sheet. In the peelability evaluation method according to claim 1,
Measure the peeling force when the adhesive sheet is peeled off at a plurality of different peeling speeds from the measurement member or the adherend to which the adhesive sheet is attached,
Based on the measured peeling force and the peeling speed at the time of measurement, calculating the peeling speed for evaluation when the adherend is peeled from the adhesive sheet by a peeling device different from that at the time of measurement. A characteristic peelability evaluation method. In the peelability evaluation method according to claim 2,
In calculating the peeling rate for evaluation,
Based on the measured peel force, calculate the fracture mechanics parameter at the time of peel for each measured peel force,
Via the measured peel force, the calculated value of the fracture mechanics parameter corresponds to the peel speed at the time of the measurement,
Based on the calculation model modeling the state at the time of peeling with the other peeling device, the fracture mechanics parameter at the time of peeling with the other peeling device is calculated,
Using the correspondence relationship between the calculated values of the peeling speed and the fracture mechanics parameter at the time of measurement, and the calculated value of the fracture mechanics parameter based on the calculation model at the time of peeling with the other peeling device, A peelability evaluation method characterized by calculating a peel rate for evaluation. In the peelability evaluation method according to claim 3,
The fracture mechanics parameter at the time of peeling with the other peeling device is calculated for each peeling area ratio that is a ratio of the peeling area to the sticking area,
The peelability is characterized by calculating the peel rate for evaluation for each peel area ratio and setting the minimum peel rate for evaluation among the calculated peel rates for evaluation as the final peel rate for evaluation. Evaluation methods. In the peelability evaluation method according to claim 3 or claim 4,
The method for evaluating peelability, wherein the fracture mechanics parameter is an energy release rate. In the peelability evaluation method according to any one of claims 1 to 5,
Each calculated value is calculated by finite element analysis, The peelability evaluation method characterized by the above-mentioned. In the peelability evaluation method according to any one of claims 1 to 6,
The adherend is a semiconductor element obtained by dicing the semiconductor wafer in a state where the semiconductor wafer is attached to the adhesive sheet;
The peelability evaluation method is applied to the case where the semiconductor element is peeled from the adhesive sheet by pushing up the surface of the adhesive sheet opposite to the sticking surface of the semiconductor element with a needle tip. Peelability evaluation method. A peelability evaluation apparatus for peeling the adherend from the adhesive sheet affixed to the adherend,
Data acquisition means for acquiring a peeling force measured by peeling the adhesive sheet from the measurement member to which the adhesive sheet is attached or the adherend at a plurality of different peeling speeds;
Based on the measured peeling force, a measurement parameter calculation means for calculating a fracture mechanics parameter at the time of peeling for each measured peeling force;
Via the measured peeling force, a measurement parameter relating means for associating the calculated value of the fracture mechanics parameter with the peeling speed at the time of the measurement,
Based on a calculation model that models the state at the time of peeling with the other peeling device, model corresponding parameter calculation means for calculating the fracture mechanics parameter at the time of peeling with the other peeling device;
Using the correspondence relationship between the calculated values of the peeling speed and the fracture mechanics parameter at the time of measurement, and the calculated value of the fracture mechanics parameter based on the calculation model at the time of peeling with the other peeling device, A peelability evaluation apparatus comprising: a peel rate calculating means for calculating a peel rate for evaluation used for evaluation of peelability. A peelability evaluation apparatus for peeling the adherend from the adhesive sheet affixed to the adherend,
A peeling force measuring device that peels the adhesive sheet from the measurement member to which the adhesive sheet is attached or the adherend at a plurality of different peeling speeds and measures the peeling force at the time of peeling,
Data acquisition means for acquiring the measured peeling force in the peeling force measuring device;
Based on the measured peeling force, a measurement parameter calculation means for calculating a fracture mechanics parameter at the time of peeling for each measured peeling force;
Via the measured peeling force, a measurement parameter relating means for associating the calculated value of the fracture mechanics parameter with the peeling speed at the time of the measurement,
Based on a calculation model that models the state at the time of peeling with the other peeling device, model corresponding parameter calculation means for calculating the fracture mechanics parameter at the time of peeling with the other peeling device;
Using the correspondence relationship between the calculated values of the peeling speed and the fracture mechanics parameter at the time of measurement, and the calculated value of the fracture mechanics parameter based on the calculation model at the time of peeling with the other peeling device, A peelability evaluation apparatus comprising: a peel rate calculating means for calculating a peel rate for evaluation used for evaluation of peelability. In the peelability evaluation apparatus according to claim 8 or 9,
The model-corresponding parameter calculation means calculates the fracture mechanics parameter at the time of peeling with the separate peeling device for each peeling area ratio that is a ratio of the peeling area to the sticking area,
The peeling rate calculation means calculates the peeling rate for evaluation for each peeling area ratio, and sets the minimum peeling rate for evaluation among the calculated peeling rates for evaluation as the final peeling rate for evaluation. A peelability evaluation apparatus characterized by that.

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