Sputter pre-treatment method

Abstract

This invention relates to a sputtering pretreatment method that, after a sputtering process, prevents burr formation, reduces defect rates, improves product reliability, and shortens process time while increasing productivity (Units Per Hour; UPH) when separating the semiconductor material from the sputtering frame. The method is characterized by using a laser to process the adhesive layer used in the sputtering process of the semiconductor material, thereby hardening the adhesive layer.

Description

Technical Field

[0001] This invention relates to a sputtering pretreatment method for forming an electromagnetic wave shielding layer in the remaining area of ​​a semiconductor material excluding the bottom surface. Specifically, this invention relates to a sputtering pretreatment method that, after the sputtering process of semiconductor material, when separating the semiconductor material from the sputtering frame, can prevent the generation of burrs, thereby reducing the defect rate and improving product reliability, and can also shorten the process time and improve productivity (Units Per Hour; UPH). Background Technology

[0002] Generally, semiconductor manufacturing processes are divided into front-end processes and back-end processes. In the semiconductor front-end processes, a patterning process is performed to etch circuits onto the wafer. In the back-end processes, the wafer is separated into small chip units, and a packaging process is performed to safely protect the semiconductor chips from various external stimuli.

[0003] In the packaging process, together with the conductor connection process that enables the chips cut into small sizes to receive and generate signals, an EMI (electromagnetic interference) shielding deposition process is completed to protect the semiconductor chip from external stimuli such as chemical reactions or temperature changes, and to prevent noise caused by interference with adjacent chips.

[0004] Semiconductor packages manufactured through the aforementioned encapsulation come in various types, and recently there has been a demand for semiconductor materials that can meet various needs, such as miniaturization, thinness, multifunctionality, and high integration that can process large amounts of information in a short time.

[0005] In the packaging process, in order to form an electromagnetic wave shielding layer to prevent noise and errors caused by electromagnetic wave interference between adjacent chips, a sputtering process is performed to form an EMI (electromagnetic interference) coating. This process forms the electromagnetic wave shielding layer on the five sides other than the bottom surface with chip electrodes.

[0006] Figure 1 This is a diagram that roughly illustrates the process of performing a sputtering operation on existing semiconductor materials. Figure 2 It is shown in magnification Figure 1 A diagram showing the semiconductor material bonded to the adhesive layer 11.

[0007] like Figure 1As shown in (a), the existing sputtering process has an adhesive layer 11 for fixing semiconductor material P on the upper surface of the film 12 of the sputtering frame, and with the semiconductor material P fixed on the upper surface of the adhesive layer 11, a sputtering deposition layer 20, i.e. an electromagnetic wave shielding layer, is formed on five surfaces other than the bottom surface of the semiconductor material P, i.e. the adhesive surface D with the adhesive layer 11.

[0008] In addition, such as Figure 1 As shown in (b), after the sputtered deposition layer 20 is formed, the semiconductor material P is adsorbed and fixed using a vacuum picker 30, such as... Figure 1 As shown in (c), after the lifting pickup 30 separates the semiconductor material P from the adhesive layer 11 of the sputtering frame, subsequent processes are performed.

[0009] The sputtered deposition layer 20 is formed by the deposition gas traveling from top to bottom. At this time, the non-contact portion between the semiconductor materials P is where the deposited material is stacked upwards, thus forming a relatively thicker layer compared to the sides of the semiconductor material P. Figure 1 As shown, a relatively thin deposit is formed on the lower side of the semiconductor material P.

[0010] Then, in this state, if the semiconductor material P is separated from the adhesive layer 11 of the sputtering frame by the pickup 30, then as Figure 1 As shown in (c), burrs 20a are generated when the thick part at the bottom is lifted together.

[0011] In particular, since the sputtered deposition layer 20 does not form a right angle but an arc shape at the corner where the semiconductor material P meets the side and the middle blank area, the probability of burrs 20a being generated is increased when the semiconductor material P is separated and broken.

[0012] Furthermore, due to the difference between the bonding force between the sputtered deposited layer 20 and the semiconductor material P and the bonding force between the sputtered deposited layer 20 and the adhesive layer 11 exposed in the non-adhesive portion, the portion with relatively weak bonding force separates first, thus aggravating the generation of burrs.

[0013] Furthermore, such as Figure 2As shown, during the process of bonding semiconductor material P to the adhesive layer 11 of the sputtering frame, a portion of the adhesive layer 11 is pushed away from the semiconductor material P by the pressure (adhesive force) applied to the adhesive layer 11, forming a protrusion h of about 30 μm to 50 μm. When the sputtering process is performed in this state, a thick sputtered deposition layer 20 is formed in the groove portion between the semiconductor material P and the protrusion h, and a relatively thin sputtered deposition layer 20 is formed in the normal portion of the protrusion h. Thus, when the semiconductor material P is separated from the adhesive layer 11 of the sputtering frame using the pickup 30, the normal portion of the protrusion with the relatively thin sputtered deposition layer becomes the broken point of the sputtered deposition layer 20, and the sputtered deposition layer 20 formed on the groove portion between the semiconductor material P and the protrusion becomes a huge burr.

[0014] As described above, if burrs 20a are generated in the sputtered deposition layer 20, a cleaning process is performed by contacting the cleaning unit in order to remove the burrs from the semiconductor material P. However, during cleaning, the scattered burrs may re-adhere to the electrodes on the lower surface of the semiconductor material. The burrs adhering to the electrodes cause short circuits, which may become a cause of reduced product reliability.

[0015] Therefore, as described in Publication Patent 10-2017-59227, in order to avoid or minimize the generation of burrs when separating the semiconductor material from the adhesive layer 11, it is desirable to use a method to remove the remaining portion of the adhesive layer 11, excluding the portion of the semiconductor material to be bonded, before fixing the semiconductor material to the adhesive layer 11. However, the removal of the adhesive layer 11 described in the published patent is generally performed by applying heat to the portion of the adhesive layer 11 to burn it off or by removing it with a blade. During this removal process, dust generated or the removed adhesive layer 11 adheres to the surface of the remaining adhesive layer 11, causing poor contact between the adhesive layer 11 and the semiconductor material. Ultimately, during the sputtering process, deposition gas intrudes between the adhesive layer 11 and the semiconductor material and deposits on the electrode, which may cause a short circuit and increase the process time, resulting in a problem that can reduce productivity (UPH).

[0016] Therefore, there is an urgent need for a method for processing an adhesive layer 11 in the sputtering process of semiconductor materials. This method can prevent the generation of burrs, reduce the defect rate, improve product reliability, and shorten process time when separating the semiconductor material from the sputtering frame after the sputtering process. Summary of the Invention

[0017] Technical issues

[0018] The purpose of this invention is to provide a sputtering pretreatment method that can prevent the generation of burrs, reduce the defect rate, and improve the reliability of products when separating semiconductor materials from the sputtering frame after the sputtering process.

[0019] In addition, the purpose of this invention is to harden the adhesive layer in the non-adhesive portion where no semiconductor material is bonded by the adhesive layer without reducing the adhesive force of the bonding area where the semiconductor material is bonded, thereby preventing the formation of protrusions when bonding the semiconductor material and preventing the generation of large burrs when peeling off the semiconductor material.

[0020] In addition, the present invention aims to provide a sputtering pretreatment method for processing adhesive layers used in the sputtering process of semiconductor materials, which can prevent the defect rate caused by the generation of burrs and improve productivity (Unit Per Hour; UPH).

[0021] Furthermore, the present invention aims to provide a sputtering pretreatment method that partially removes the adhesive layer during processing, thereby preventing dust generation and contamination of the adhesive layer and maintaining its performance.

[0022] Technical solution

[0023] To address the aforementioned issues, the present invention provides a sputtering pretreatment method for forming an electromagnetic wave shielding layer in a region other than the bottom surface of a semiconductor material. The method includes: preparing a semiconductor material bonding component to form an adhesive layer on the bottom surface of the semiconductor material to be bonded; setting adhesive layer processing areas spaced at predetermined intervals from the bonding area on the bottom surface of the semiconductor material to be bonded outwards; and irradiating the adhesive layer processing areas with a laser to harden the adhesive layer.

[0024] One of the methods provides a sputtering pretreatment method, characterized in that, before performing the step of hardening the adhesive layer, it further includes: irradiating a laser along the inner edge of the processing area of ​​the adhesive layer to process a first cutting line of the adhesive layer; and irradiating a laser along the outer edge of the processing area of ​​the adhesive layer to process a second cutting line of the adhesive layer.

[0025] Additionally, a sputtering pretreatment method is provided, characterized in that, before performing the step of hardening the adhesive layer 11, it further includes: irradiating a laser along the outer edge of the processing area of ​​the adhesive layer to process a second cutting line of the adhesive layer; and irradiating a laser along the inner edge of the processing area of ​​the adhesive layer to process a first cutting line of the adhesive layer.

[0026] Then, a sputtering pretreatment method is provided, characterized in that, before performing the step of hardening the adhesive layer, it further includes: irradiating a laser along one or more of the inner and outer edges of the processing area of ​​the adhesive layer, thereby processing a cutting line of the adhesive layer so that the thermal energy of the irradiated laser is indirectly transferred to the adhesive area where the semiconductor material is to be bonded.

[0027] On the one hand, a sputtering pretreatment method is provided, characterized in that the energy intensity of each unit area of ​​the laser irradiating the inner edge is greater than the energy intensity of each unit area of ​​the laser irradiating the outer edge.

[0028] One of the methods is a sputtering pretreatment method, characterized in that the laser irradiating the inner edge is controlled to have a slower moving speed, a higher repetition rate, or a stronger irradiation intensity compared to the laser irradiating the outer edge.

[0029] In addition, a sputtering pretreatment method is provided, characterized in that the step of hardening the adhesive layer is to irradiate the processing area of ​​the adhesive layer with a continuous quadrilateral spiral trajectory pattern from the inside to the outside.

[0030] On the one hand, a sputtering pretreatment method is provided, characterized in that the semiconductor material bonding component is a frame with an adhesive layer coated on the upper part or an adhesive tape with an adhesive layer.

[0031] One of the methods is a sputtering pretreatment method, characterized in that a perforation or receiving groove is formed in the frame or the tape for accommodating solder balls formed under the semiconductor material.

[0032] Invention Effects

[0033] According to the sputtering pretreatment method of the present invention, by processing the perimeter of the bonding region where the semiconductor material is bonded in the adhesive layer in a novel way, the generation of burrs can be prevented when separating the semiconductor material from the adhesive layer after the sputtering process is performed on the semiconductor material, thereby reducing the defect rate and improving the reliability of the product, thus showing excellent results.

[0034] In addition, according to the sputtering pretreatment method of the present invention, a region separated from the bonding area of ​​the bottom surface of the semiconductor material to be bonded by a predetermined interval is set as a processing area, and a laser is irradiated onto the processing area to harden the bonding layer, thereby having the effect of preventing the generation of burrs.

[0035] Furthermore, according to the sputtering pretreatment method of the present invention, the adhesive layer is locally hardened and the thermal energy of the laser is indirectly transferred to the adhesive area, thereby increasing the recovery force of the adhesive layer without reducing the adhesive force of the adhesive area where the semiconductor material is bonded, and thus preventing the generation of burrs when peeling off the semiconductor material.

[0036] Furthermore, according to the sputtering pretreatment method of the present invention, by processing the adhesive layer in a novel manner, dust does not adhere to the adhesive layer during processing, and when separating the semiconductor material after sputtering through the adhesive layer processing, burrs can be prevented, process defects can be avoided, process time can be shortened, and productivity (UPH) can be improved, thus showing excellent results.

[0037] Then, according to the sputtering pretreatment method of the present invention, the adhesive layer is partially removed without complete removal, thereby showing the effect of preventing the adhesive layer from being contaminated by dust generated during the removal of the adhesive layer.

[0038] Furthermore, according to the sputtering pretreatment method of the present invention, after processing the inner and outer edges of the adhesive layer processing area, a laser is irradiated onto the adhesive layer processing area, thereby achieving the effect of guiding the hardening range and the amount of hardening of the adhesive layer by the laser.

[0039] Furthermore, according to the sputtering pretreatment method of the present invention, during laser processing, the inner and outer edges are preferentially processed in the heat transfer area, thereby achieving the effect of separating the laser processing area and the external area and uniformly adjusting the thermal influence.

[0040] Furthermore, when the adhesive layer is processed by the sputtering pretreatment method according to the present invention, even after the semiconductor material is bonded and sputtering is performed, and the sputtered semiconductor material is peeled off from the adhesive layer, no burrs are generated on the contact surface of the semiconductor material. Therefore, it is shown that in relation to the circuit structure surrounding the semiconductor material, it can prevent short circuits. Attached Figure Description

[0041] Figure 1 This diagram schematically illustrates the process of separating the semiconductor material from the adhesive layer after a sputtering process is performed on existing semiconductor material.

[0042] Figure 2 It is shown in magnification Figure 1 A diagram showing the situation where semiconductor materials are bonded to the adhesive layer.

[0043] Figure 3 This is a diagram that schematically illustrates the process of forming an adhesive layer on a semiconductor material bonding component.

[0044] Figure 4These are diagrams showing the processing patterns applied in the sputtering pretreatment method according to the present invention.

[0045] Figure 5 It shows through Figure 4 The diagram shows the processing patterns of the adhesive layer processing area.

[0046] Figure 6 This is a diagram that roughly illustrates the heat transfer that occurs during laser processing.

[0047] Figure 7 It is a magnified display based on Figure 6 Figure (a) shows the results of laser processing.

[0048] Figure 8 It fully demonstrates the basis Figure 6 Figure (a) shows the results of laser processing.

[0049] Figure label:

[0050] 100: First cutting line; 200: Second cutting line

[0051] 300: Heating wire Detailed Implementation

[0052] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein, and may be embodied in other forms. Rather, the embodiments described herein are provided to make the disclosure comprehensive and complete, and to fully convey the inventive concept to those skilled in the art. Throughout the specification, the same reference numerals denote the same constituent elements.

[0053] Figure 3 This is a diagram that schematically illustrates the process of forming an adhesive layer on a semiconductor material bonding component.

[0054] like Figure 3 As shown, the sputtering process for forming an electromagnetic wave shielding layer (EMI coating) on ​​the surface of a semiconductor material is performed with the bottom surface of the semiconductor material fixed in place by an adhesive layer 11 formed on the upper surface of the semiconductor material bonding component. After the sputtering process is completed, when the semiconductor material is peeled off from the adhesive layer 11 on the upper surface of the sputtering frame S, a portion of the electromagnetic wave shielding layer that is stacked between adjacent semiconductor materials is separated together at the lower end of the side of the semiconductor material, thereby forming a burr. In order to avoid or minimize the generation of burrs, the adhesive layer 11 is pre-processed with a laser before fixing the semiconductor material to the adhesive layer 11.

[0055] Therefore, the present invention provides a sputtering pretreatment method for pre-processing an adhesive layer 11 using a laser. The sputtering pretreatment method according to the present invention for forming an electromagnetic wave shielding layer in the remaining area excluding the underside of a semiconductor material includes: a step of preparing a semiconductor material bonding component to form an adhesive layer 11 to be bonded to the bottom surface of the semiconductor material; a step of setting an adhesive layer 11 processing area spaced outward from the bonding area to be bonded to the bottom surface of the semiconductor material; and a step of irradiating the adhesive layer 11 processing area with a laser to harden the adhesive layer 11.

[0056] First, a semiconductor material bonding component is prepared, which has an adhesive layer 11 on the bottom surface of the semiconductor material to be bonded. The semiconductor material bonding component may be a frame with an adhesive layer 11 coated on its top and the semiconductor material is fixed by the adhesive layer 11, or it may be an adhesive tape with an adhesive layer 11 on the bottom surface of the semiconductor material to be bonded.

[0057] When the semiconductor material bonding component is a frame, the frame can be a flat plate-type stencil. To bond and fix the material on the stencil, EMI sputtering can be performed on the top and sides of the material after applying the adhesive (adhesive layer 11) and bonding the bottom surface of the material. In this case, through-holes T or receiving grooves smaller than the material can be formed on the frame to accommodate solder balls formed on the bottom of the material.

[0058] Figure 3 The illustration shows a sputtering process performed while the material is adhered to a tape, with the adhesive layer 11 of the tape bonded to the sputtering frame S with its upward orientation. The adhesive layer 11 is formed on the top surface of the tape, and a support plate 12, such as a polyimide (PI) film, is provided on the bottom surface. At this time, the semiconductor material with solder balls formed is in a state where through-holes T are formed to accommodate the solder balls, preventing EMI coating from being applied to the bottom surface of the semiconductor material with the solder balls. The peripheral area on the bottom surface of the semiconductor material where no solder balls are formed becomes the adhesive area bonded to the adhesive layer 11 of the tape.

[0059] That is, in the state before processing, multiple through holes T are formed to accommodate solder balls formed on the bottom surface of the semiconductor material. An adhesive layer 11 of tape is present between the through holes T, such that the edge region of the bottom surface is bonded to the adhesive layer 11 when the through holes T accommodate the solder balls formed on the bottom surface of the semiconductor material. The region in the adhesive layer 11 where the semiconductor material is bonded can be referred to as the adhesive region.

[0060] For reference, the bottom surface of the semiconductor material can also have a flat lead instead of a solder ball, or if the diameter of the solder ball is small, it can be directly attached to the bottom surface of the semiconductor material on top of the tape instead of avoiding the through hole T, thereby bonding and fixing it.

[0061] In this case, the solder balls formed on the lower surface of the semiconductor material by the elasticity of the support plate 12 and the adhesive layer 11 press the adhesive layer 11, thereby the lower surface of the semiconductor material is tightly attached to the adhesive layer 11 and can be bonded and fixed, and the entire lower surface of the semiconductor material becomes the bonding area.

[0062] On the one hand, Figure 3 In the above, the part represented by "b" is the case where the perforation T is formed. The lower edge of the semiconductor material needs to be bonded and fixed to the tape. Therefore, the remaining area of ​​the adhesive layer 11 other than the area of ​​the bottom surface of the semiconductor material to be bonded and fixed (adhesive area) (adhesive layer 11 of the non-adhesive part) can become the processing area of ​​adhesive layer 11.

[0063] The size of the perforation T is smaller than the size of the lower surface of the semiconductor material so that the perimeter of the semiconductor material can contact the adhesive layer 11. Considering the size of the lower surface of the semiconductor material bonded to the adhesive layer 11, the adhesive layer 11 is processed along the perimeter of the area where the lower surface of the semiconductor material is bonded. This avoids or minimizes the generation of burrs when separating the semiconductor material after the sputtering process. Figure 3 The part indicated by "a" refers to the case where the adhesive layer 11 of the non-adhesive part is processed by laser processing to form the adhesive layer 11.

[0064] The following is for reference. Figures 4 to 8 This invention describes the sputtering pretreatment method.

[0065] Figure 4 These are diagrams showing, in sequence, the processing patterns applied in an embodiment of the sputtering pretreatment method according to the present invention. Figure 5 It shows through Figure 4 The diagram shows the processing pattern and all processed areas of the adhesive layer 11. Figure 6 This is a diagram that roughly illustrates the heat transfer that occurs during laser processing. Figure 7 It is a magnified display based on Figure 6 Figure (a) shows the laser processing results. Figure 8 It fully demonstrates the basis Figure 6 Figure (a) shows the results of laser processing.

[0066] This invention relates to a sputtering pretreatment method, specifically a method for hardening a portion of an adhesive layer 11 used in a sputtering process of semiconductor materials using a laser. The method is characterized by hardening the adhesive layer 11 by transferring adjusted thermal energy to a targeted portion of the adhesive layer 11 through a laser-processed pattern. In this case, the hardening of the adhesive layer 11 occurs near the bonding area on the bottom surface of the semiconductor material to be bonded, rather than within the processing area of ​​the adhesive layer 11, where the bottom surface of the semiconductor material indirectly receives the thermal energy of the laser irradiating the processing area of ​​the adhesive layer 11.

[0067] Therefore, the sputtering pretreatment method of the present invention includes: a step of preparing a semiconductor material bonding component for forming an adhesive layer 11 on the bottom surface of a semiconductor material to be bonded; a step of setting an adhesive layer 11 processing area spaced outward from the bonding area on the bottom surface of the semiconductor material to be bonded; and a step of irradiating the set adhesive layer 11 processing area with a laser to harden the adhesive layer 11.

[0068] At this point, before the step of hardening the adhesive layer 11, a step of cutting the inner and outer edges of the processing area of ​​the adhesive layer 11 to separate the processing area of ​​the adhesive layer 11 from the outer area can be performed.

[0069] That is, before the step of hardening the adhesive layer 11, the following can be performed: Figure 4 As shown in (a), the steps of irradiating the inner edge of the processing area of ​​the adhesive layer 11 with a laser to process the first cutting line 100 of the adhesive layer 11 are as follows: Figure 4 As shown in (b), the second cutting line 200 of the adhesive layer 11 is processed by irradiating a laser along the outer edge of the processing area of ​​the adhesive layer 11.

[0070] The steps of processing the first cutting line 100 and processing the second cutting line 200 can be as follows: Figure 4 As shown, the second cutting line can be processed after the first cutting line is processed, or the second cutting line can be processed first and then the first cutting line is processed.

[0071] When laser is irradiated onto the processing area of ​​the adhesive layer 11 through the first and second cutting lines, the heat energy of the irradiated laser is indirectly transferred to the bonding area of ​​the semiconductor material to be bonded. Moreover, when the processing area of ​​the adhesive layer 11 is separated from the external area, laser is irradiated onto the processing area of ​​the adhesive layer 11, thereby extending the hardening range and hardening amount of the adhesive layer 11 to a certain level.

[0072] Alternatively, a laser can be irradiated along one or more of the inner and outer edges of the processing area of ​​the adhesive layer 11 to process the cutting line of the adhesive layer 11 so that the heat energy of the irradiated laser is indirectly transferred to the bonding area to be bonded with the semiconductor material. Preferably, the laser can be irradiated towards the inner edge of the processing area of ​​the adhesive layer 11 to indirectly transfer heat energy to the bonding area to be bonded with the semiconductor material and uniformly guide the thermal influence.

[0073] In this invention, the step of processing the cutting line may include either completely cutting the adhesive layer 11 or partially cutting to remove a portion of the adhesive layer 11.

[0074] In particular, the step of cutting the first cutting line 100 can be to completely cut the adhesive layer 11 so that the heat energy of the laser irradiating the processing area of ​​the adhesive layer 11 is shielded by the first cutting line, so that the heat is not directly transferred to the outside of the adhesive area under the semiconductor material to be bonded through the adhesive layer 11 as a medium, but is indirectly transferred through the air as a medium.

[0075] Of course, when the first cutting line is cut, the surface of the adhesive layer 11 is pushed apart by the adhesive force between the surface of the adhesive area and the semiconductor material, and the surface of the protrusion is generated. The heat energy of the laser can also be indirectly transferred through partial cutting, thereby hardening the surface of the adhesive layer 11.

[0076] In addition, the cutting of the second cutting line 200 can be selectively performed to completely or partially cut the adhesive layer 11. In the case of partially cutting the second cutting line 200, when the laser is irradiated along the heating line 300, the adhesive layer 11 that has received heat energy is not completely peeled off and remains, thus preventing the problem of completely peeled adhesive layer 11 fragments or dust contaminating the semiconductor material or processing device.

[0077] At this point, if the intensity of the energy irradiated per unit area of ​​the processing area of ​​the adhesive layer 11 is compared, it is characterized in that the intensity of the energy irradiated per unit area of ​​the laser irradiated towards the inner edge is greater than the intensity of the energy irradiated per unit area of ​​the laser irradiated towards the outer edge.

[0078] Therefore, the laser moving speed can be controlled to be slower when irradiating the inner edge compared to the laser irradiating the outer edge. The laser repetition rate can also be increased to reduce the laser pulse period. The intensity of energy irradiated per unit area can be increased by strongly controlling the laser irradiation intensity.

[0079] In addition, to increase the energy intensity per unit area of ​​the laser irradiating the inner edge, the number of laser irradiations can be varied. For example, if the laser is irradiated once along the outer edge, irradiating twice along the inner edge can increase the energy intensity of the laser irradiating the inner edge.

[0080] For reference, in this invention, the sputtering pretreatment method is used to process the adhesive layer 11 used in the sputtering process of semiconductor materials. In each step constituting the sputtering pretreatment method, a laser is used when cutting or processing the adhesive layer 11, preferably a pulsed laser.

[0081] Pulsed laser processing, as a processing method utilizing a laser oscillator that is discontinuously irradiated with a high-intensity laser at a certain period, is addressed in this invention by performing pulsed laser processing on an adhesive layer 11 composed of polymer materials such as silicon, polyurethane, and polypropylene. This prevents the problem of excessive heat generation around the processing area of ​​the adhesive layer 11, i.e., the bonding area of ​​the semiconductor material that does not need to be processed, from being processed in unwanted areas, causing the adhesive layer 11 to melt or become excessively hardened, thereby reducing the adhesion strength, during continuous wave (CW) laser processing with a high-intensity laser. In other words, it is difficult to achieve precise processing of the selected area of ​​the adhesive layer 11 using continuous wave (CW) lasers.

[0082] Conversely, since pulsed laser processing involves discontinuous laser irradiation, the laser is not irradiated with uniform intensity. Therefore, even when irradiated along the first cutting line 100 or the second cutting line 200, areas strongly affected by the pulse and areas not affected by the pulse will be created. Consequently, in the areas strongly affected by the pulse, a significant portion of the adhesive layer 11 is removed, while in the areas not affected by the pulse, only a small amount of the adhesive layer 11 is removed, resulting in a rough, uneven surface. Furthermore, during the first pulsed laser irradiation, laser burrs remain at the boundary regions of the adhesive layer 11 due to the laser pulse.

[0083] That is, after the first pulsed laser irradiation, the phase of the laser pulse is delayed during the second irradiation. For example, based on the phase of the laser pulse during the first irradiation, the phase of the laser pulse is irradiated by 180° during the second irradiation, thereby moving the position of the intensely irradiated laser and causing the energy of the laser pulse to be overlapped and dispersed, so that the intensity of the energy applied to the processing surface can be processed at a similar level.

[0084] On the one hand, when the first cutting line 100 is cut, the second cutting line 200 is cut at least partially, and the heating line 300 is heated by the pulsed laser, the intensity, moving speed, number of irradiations, pulse period (laser repetition rate), etc. of the laser can be adjusted to control the cutting depth and heating level of the adhesive layer 11.

[0085] For example, the cutting of the first cutting line 100 can be achieved by increasing the laser intensity or decreasing the movement speed of the irradiated laser, or by shortening the laser pulse period to increase the laser repetition rate, or by increasing the number of laser irradiations, thereby completely cutting the adhesive layer 11. Conversely, the partial cutting of the second cutting line 200 can be achieved by reducing the laser intensity or increasing the laser movement speed compared to the laser intensity and laser movement speed at the time of cutting the first cutting line 100, thereby reducing the heat energy transferred to the adhesive layer 11. Similarly, the heating of the heating line 300 can be achieved by reducing the laser intensity or increasing the laser movement speed compared to the laser intensity and laser movement speed at the time of cutting the second cutting line 200, thereby reducing the heat energy transferred to the adhesive layer 11.

[0086] like Figure 6 As shown in (a), when a laser is irradiated along the heating line 300 onto the adhesive layer 11 region between the first cutting line 100 and the second cutting line 200, the adhesive layer 11 in this region receives heat energy as it is irradiated by the laser. The adhesive layer 11 region, which is bonded to the semiconductor material P on the left side of the first cutting line 100, cannot directly receive the heat energy conducted through the adhesive layer 11 as a medium due to the first cutting line 100. Instead, it can only receive heat energy limited by convection through the surrounding air of the first cutting line 100, i.e., the air surrounding the portion irradiated by the laser, thus... Figure 7 As shown, in the adhesive layer 11 disposed to the left of the first cutting line 100, the region of the adhesive layer 11 disposed outside the region where the semiconductor material P is bonded is subjected to localized and relatively uniform hardening c.

[0087] That is, the adhesive layer 11 is generally composed of a mixture of rubber such as silicone, polyurethane, and polypropylene and a hardener. When exposed to heat, it hardens simultaneously through a cross-linking reaction between the rubber and the hardener, becoming a polymer. This also increases the resilience of the hardened areas of the adhesive layer 11, thereby preventing damage caused by pressure on the semiconductor material during the bonding of the semiconductor material P to the adhesive layer 11. Figure 2 The generation of protrusions or the protrusion height being minimized to be 5μm to 10μm can avoid or minimize burrs generated through the protrusions of the adhesive layer 11.

[0088] On the one hand, such as Figure 6 As shown in (b), when the adhesive layer 11 is not cut based on the first cutting line 100, when a laser is irradiated onto the adhesive layer 11, the heat energy transferred by the irradiated laser is conducted through the adhesive layer 11 as a medium and is thus transferred to the region of the adhesive layer 11 to which the semiconductor material P is bonded, resulting in over-hardening and irregular hardening of the adhesive layer 11, which ultimately significantly reduces the adhesive force of the adhesive layer 11, thereby causing the problem of unstable bonding of the semiconductor material P.

[0089] Furthermore, in order to adjust the degree of hardening of the adhesive layer 11 region by adjusting the heat energy transferred to the region where the semiconductor material P is bonded, the density and crosslinking degree of the hardening agent dispersed in the rubber such as silicon, polyurethane, and polypropylene that forms the adhesive layer 11 are uneven. Therefore, the degree of hardening of the adhesive layer 11 region cannot be adjusted simply by adjusting the laser intensity or the laser movement speed.

[0090] To elaborate further, the adhesive layer 11 does not have a uniform density but consists of dense and sparse regions. Therefore, the amount of heat energy transferred during laser processing will vary. That is, even if the same amount of heat energy is transferred from the laser, the amount of heat energy transferred varies depending on the density of the adhesive layer 11, resulting in areas with more hardening and areas with less hardening. Therefore, when laser energy is irradiated onto the processing area of ​​the adhesive layer 11, the irradiated heat energy is directly transferred to the adhesive layer 11 to which the semiconductor material is bonded, making it difficult to predict the area and degree of hardening, thus making it difficult to ensure the quality of hardening. When excessive hardening occurs in the adhesive layer 11, the adhesive force of the semiconductor material decreases, and the semiconductor material may not adhere to the adhesive area or gaps may form between the adhesive area and the semiconductor material. As a result, electromagnetic shielding material may be transferred to the underside of the semiconductor material through these gaps, potentially leading to defects.

[0091] Therefore, in this invention, considering that the adhesive layer 11 does not have a uniform density, before irradiating the processing area of ​​the adhesive layer 11 with a laser, one or more of the inner and outer edges of the processing area of ​​the adhesive layer 11 are cut to separate or block it from the external area. As a result, the heat energy of the laser irradiated into the processing area of ​​the adhesive layer 11 is not directly transferred to the adhesive area through the adhesive layer 11 as a medium, but is indirectly transferred to the adhesive area through the air as a medium, thereby achieving the effect of uniformly adjusting the heat effect on the adhesive area.

[0092] Therefore, before performing the step of irradiating the processing area of ​​the adhesive layer 11 with a laser to harden the adhesive layer 11, the laser can be irradiated along at least one of the inner and outer edges of the processing area of ​​the adhesive layer 11, so that the heat energy of the laser is indirectly transferred to the outer region of the adhesive area of ​​the semiconductor material to be bonded.

[0093] When performing the step of irradiating the processing area of ​​the adhesive layer 11 with a laser to harden the adhesive layer 11, as follows: Figure 4 As shown in (c), preferably, the laser is irradiated with a continuous quadrilateral spiral trajectory pattern from the inside to the outside of the processing area of ​​the adhesive layer 11. That is, the laser can be irradiated with a quadrilateral spiral trajectory pattern that is rolled sequentially and continuously from the inside to the outside of the processing area of ​​the adhesive layer 11.

[0094] When the laser is irradiated along the heating line 300 with the spiral trajectory pattern, the processing work can be performed once from start to finish along the heating line 300 with the laser irradiation device on, thereby improving productivity (UPH).

[0095] At this point, the intervals of the spiral trajectory can be formed at the same interval, or the intervals can be changed as needed.

[0096] Instead of focusing the laser on any one area, the laser is irradiated from the inside to the outside, thereby guiding the removal direction of the adhesive layer 11 in the outward direction. As a result, the adhesive layer 11 does not fall off but remains in a form that curls up and rises toward the second cutting line.

[0097] Of course, when the present invention irradiates the laser with a spiral trajectory pattern, it does not exclude the situation of continuous irradiation from the outside to the inside. However, since the adhesive layer 11 that rolls up with the direction of laser movement may stick to the adhesive area or cause an effect during sputtering, it is preferable to require continuous irradiation from the inside to the outside.

[0098] On the one hand, instead of the quadrilateral spiral trajectory pattern, lasers can be irradiated laterally on each face from the inside to the outside to harden the adhesive layer 11. In this way, the adhesive layer 11 is hardened on each of the four faces in turn.

[0099] Alternatively, instead of a quadrilateral spiral trajectory pattern, the laser can be irradiated along a gradually increasing quadrilateral trajectory to harden the four faces of the adhesive layer 11. Therefore, it is necessary to control the laser's on / off state each time irradiation of a quadrilateral trajectory ends.

[0100] Therefore, continuous processing can be performed without turning the laser off and on again in the middle, and there is no need to control the laser's on / off state, which can shorten the laser's movement path. At this point, it is preferable to irradiate the laser with a quadrilateral spiral trajectory pattern.

[0101] In addition, when the laser is irradiated, the adhesive layer 11, which is cut by the first cutting line, gradually rolls up from the inside to the outside due to the heat of the laser and the direction of laser movement. If a quadrilateral spiral route that gradually increases in size from the inside to the outside is used, the adhesive layer 11 can roll up from the inside to the outside more easily.

[0102] When a laser is irradiated with a quadrilateral spiral trajectory pattern, it means that the laser is continuously irradiated from the inside to the outside, that is, from the direction away from the bonding area where the semiconductor material is bonded. In this case, the starting point of the laser can be the outside of the inner edge, and the ending point of the laser can be the inside of the outer edge.

[0103] That is, such as Figure 4 as well as Figure 5 As shown, Figure 4 The heating wire 300 of (c) can also be formed as a ratio Figure 4 The first cutting line 100 in (a) is larger than the second cutting line 200. Therefore, when the second cutting line 200, which serves as the processing area of ​​the adhesive layer 11, is partially cut, the adhesive layer 11 at the outer edge is as follows: Figure 7 as well as Figure 8 As shown, the residue remains on the support plate 12, thereby minimizing the dust generated during the laser irradiation of the processing area of ​​the adhesive layer 11, while preventing the adhesive layer 11 from falling off and not affecting the adhesive performance of the adhesive area.

[0104] Furthermore, when the second cutting line, which serves as the processing area for the adhesive layer 11, is completely cut, the laser irradiation also ends at the inner side of the outer edge of the quadrilateral spiral trajectory pattern, so that the adhesive layer 11 can remain on the support plate 12. Therefore, if the sputtering pretreatment method of the present invention is performed, it is possible to achieve the desired effect. Figure 7 as well as Figure 8 The adhesive layer 11 is processed in the shape shown.

[0105] Furthermore, such as Figure 6 As shown in (a), when a laser is irradiated along the heating line 300 into the processing area of ​​the adhesive layer 11 between the first cutting line 100 and the second cutting line 200, the second cutting line 200 can at least partially suppress the heat energy transferred therefrom from being transferred to the right side of the second cutting line 200, thereby making it easier to adjust the degree of heat energy transfer in the non-uniform adhesive layer 11 and the resulting degree of hardening of the adhesive layer 11.

[0106] Furthermore, when the second cutting line 200 is partially cut and laser light is irradiated along the heating line 300 into the adhesive layer 11 region between the first cutting line 100 and the second cutting line 200, the adhesive layer 11 in that region is not completely peeled off or removed, but rather... Figure 7 as well as Figure 8 As shown, the residue remains in a form that curls upward toward the second cutting line 200, thereby suppressing the problem of the adhesion strength of the semiconductor material weakening due to the adhesion of completely peeled or removed adhesive layer 11 fragments or dust adhering to the adhesion area of ​​the semiconductor material P, and the situation where gaps are formed between the adhesion area and the lower surface of the semiconductor material, resulting in the deposition of substances that contaminate the electrode.

[0107] On the one hand, the support plate 12 can also be the polyimide film layer of the tape, or the frame for coating the adhesive layer 11.

[0108] When the adhesive layer 11 is processed by the sputtering pretreatment method according to the present invention, sputtering is performed after the semiconductor material is bonded and fixed to the adhesive area in subsequent processes. When the sputtered semiconductor material is separated from the adhesive area, the generation of burrs can be prevented, the defect rate can be significantly reduced, and the productivity of the product can be improved.

[0109] As mentioned above, the sputtering pretreatment method according to the present invention involves irradiating a certain area separated from the area where the semiconductor material is bonded in the adhesive layer 11 with a laser in a novel manner, i.e., excluding or including a portion of the area where the semiconductor material is bonded, while simultaneously hardening and processing the adjacent area to the outside. As a result, when the semiconductor material is separated from the sputtering frame after the sputtering process, the generation of burrs can be prevented, the defect rate can be reduced, and the reliability of the product can be improved, thus demonstrating excellent results.

[0110] Furthermore, according to the sputtering pretreatment method of the present invention, the adhesive layer 11 is processed in a novel manner, thereby generating almost no dust during processing, avoiding process defects, shortening process time, and improving productivity (UPH), thus demonstrating excellent results.

[0111] Then, according to the sputtering pretreatment method of the present invention, the adhesive layer 11 is partially removed without complete removal, thereby showing the effect of preventing the adhesive layer 11 from being contaminated by dust generated during the removal of the adhesive layer 11.

[0112] Furthermore, when the adhesive layer 11 is processed by the sputtering pretreatment method according to the present invention, even after the semiconductor material is bonded and sputtering is performed, and the sputtered semiconductor material is peeled off from the adhesive layer 11, no burrs are generated on the contact surface of the semiconductor material. Therefore, it is shown that in relation to the circuit structure surrounding the semiconductor material, it is possible to prevent short circuits.

[0113] The invention has been described above with reference to one embodiment; however, those skilled in the art can make various modifications and variations to the invention without departing from the concept and scope of the invention as set forth in the patent claims below. Therefore, any variation that substantially includes the constituent elements of the patent claims of the invention is considered to be fully included within the technical scope of the invention.

Claims

1. A sputtering pretreatment method for forming an electromagnetic wave shielding layer in a region other than the bottom surface of a semiconductor material, the method comprising: The step of preparing a semiconductor material bonding component to form an adhesive layer on the bottom surface of the semiconductor material to be bonded; The step of setting up adhesive layer processing areas spaced at predetermined intervals from the adhesive area on the bottom surface of the semiconductor material to be bonded outwards; The steps are as follows: irradiating the inner edge of the adhesive layer processing area with a laser to process the first cutting line of the adhesive layer, and then irradiating the outer edge of the adhesive layer processing area with a laser to process the second cutting line of the adhesive layer; or After irradiating the adhesive layer processing area with a laser to process the second cutting line of the adhesive layer, the adhesive layer processing area is then irradiated with a laser to process the first cutting line of the adhesive layer; and The step of irradiating the processing area of ​​the adhesive layer with a laser to harden the adhesive layer.

2. A sputtering pretreatment method for forming an electromagnetic wave shielding layer in the remaining area excluding the bottom surface of a semiconductor material, the method comprising: The step of preparing a semiconductor material bonding component to form an adhesive layer on the bottom surface of the semiconductor material to be bonded; The step of setting up adhesive layer processing areas spaced at predetermined intervals from the adhesive area on the bottom surface of the semiconductor material to be bonded outwards; The steps include: irradiating a laser along one or more of the inner and outer edges of the adhesive layer processing area to create a cutting line in the adhesive layer so that the heat energy of the irradiated laser is indirectly transferred to the adhesive area where the semiconductor material is to be bonded; and... The step of irradiating the processing area of ​​the adhesive layer with a laser to harden the adhesive layer.

3. The sputtering pretreatment method according to any one of claims 1 or 2, characterized in that, The energy intensity of the laser irradiating the inner edge per unit area is greater than the energy intensity of the laser irradiating the outer edge per unit area.

4. The sputtering pretreatment method according to claim 3, characterized in that, Compared to the laser irradiating the outer edge, the laser moving speed is slower, the repetition rate is increased, or the irradiation intensity is stronger when the laser irradiates towards the inner edge.

5. The sputtering pretreatment method according to any one of claims 1 or 4, characterized in that, The step of hardening the adhesive layer is to irradiate the processing area of ​​the adhesive layer with a laser in a continuous quadrilateral spiral trajectory pattern from the inside to the outside.

6. The sputtering pretreatment method according to claim 1 or 4, characterized in that, The semiconductor material bonding component is... A frame with an adhesive layer applied to the top; or Adhesive tape with an adhesive layer.

7. The sputtering pretreatment method according to claim 6, characterized in that, The frame or the tape has perforations or receiving grooves for accommodating solder balls formed on the bottom surface of the semiconductor material.

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