JP2005341524A - Mounting method of video sensor and adhesive tape used therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting method of a video sensor capable of attaining solder reflow in a state that an adhesive tape is adhered to a light receiving side of the video sensor and protecting the light receiving side of the video sensor even during the solder reflow in a mounting step of the video sensor employing a solid-state imaging device and to provide the protective adhesive tape used for the method. <P>SOLUTION: The mounting method is characterized in that solder connection reflow is applied to terminals of the video sensor with a board side by heating the terminals at a temperature of 170 °C or over while the adhesive tape employing a polyimide film for a configuration material of the its material is adhered to the light receiving side of the video sensor, the adhesive tape having an adhesive coated on one side and an anti-static agent coated on the other side. Further, at least a silicone group material is characterized in to be used for the adhesive configuration material of the adhesive tape. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mounting process of a video sensor using a solid-state imaging device.

  In recent years, image sensors using solid-state imaging devices have been widely used in digital cameras, video cameras, and the like. In the manufacturing process including mounting of the image sensor on the substrate side, scratches on the surface of the image sensor and adhesion of dust are highly likely to directly affect imaging. In view of this, a technique is adopted in which an adhesive tape is used as a surface protection tape and is attached to the light receiving portion side of the image sensor to avoid scratches and dust from being attached in the mounting and manufacturing process.

  On the other hand, when mounting an image sensor on a substrate or the like, a technique has been used so far in which a terminal portion is soldered and mounted using a soldering iron. In recent years, with the increase in image quality and functionality of video sensors, the number of terminals has also increased dramatically. Therefore, soldering and mounting each terminal using a soldering iron requires a considerable amount of time and is a reality. Not right. In view of this, a method of connecting and mounting at a time by putting the terminal portion of the image sensor and the mounting substrate into a solder reflow furnace in an aligned state is often used.

  However, the solder reflow furnace needs to be heated to a high temperature at least equal to or higher than the melting point of the solder. If the heat reflow is performed with the adhesive tape for the above protection attached, the displacement of the adhesive tape base material due to thermal deformation and shrinkage, or degradation due to the thermal deterioration of the adhesive tape material may appear on the surface of the image sensor. Conversely, it can cause contamination. In addition, since the color filter used inside the solid-state imaging device may be denatured or damaged by heat, the reflow process itself at a high temperature of 170 ° C. or higher is particularly difficult.

  Therefore, conventionally, the protective tape was once peeled off immediately before being put into the solder reflow furnace, the solder reflow was performed at about 160 ° C., and the protective tape was reapplied after the completion. Thus, it has been difficult to go through a high heating process for solder reflow in a state where the adhesive tape is still bonded.

  In addition, the method of using an adhesive tape for surface protection has the advantage that the pasting and peeling process is simple, but on the other hand, the adhesive tape as well as the adherend are transferred due to the movement of the charge generated when the adhesive tape is applied. Charges and accompanies discharge during peeling. In recent years, with the miniaturization and high integration of electronic devices, circuit precision has been measured, but the resistance to discharge of electronic devices has declined, and the phenomenon that electronic devices can be destroyed by discharge during tape peeling has occurred. ing.

  Accordingly, an object of the present invention is to enable solder reflow in a mounting process of a video sensor using a solid-state imaging device while the adhesive tape is stuck on the light receiving side of the video sensor, and also during the solder reflow. It is in providing the mounting method of the image sensor which can protect the light-receiving side, and the protective adhesive tape used therefor.

  It is another object of the present invention to provide a surface protective adhesive film having an effect of preventing the generation of static electricity accompanying the peeling and the destruction of the device due to the discharge caused by the peeling in the peeling process of the adhesive tape from the image sensor.

  As a result of intensive studies to solve the above problems, the present inventors have found that the object can be achieved by using a mounting method or an adhesive tape described below, and have completed the present invention.

  The present invention is a method for mounting a video sensor, and in a video sensor mounting process using a solid-state imaging device, a polyimide film is used as a constituent material of a base material on the light receiving part side of the video sensor, and an adhesive layer is provided on one side. And having the adhesive tape to which the antistatic agent is applied on the other surface attached thereto, the terminal portion of the video sensor is solder-reflowed to the substrate side by heating to 170 ° C. or higher.

  According to the present invention, the high heat resistance of polyimide makes it possible not only to suppress significant thermal deformation and shrinkage of the adhesive tape in the high temperature process during solder reflow, but also to provide high light shielding and low thermal conductivity specific to polyimide films. Depending on the degree, it is possible to suppress the conduction of heat to the color filter used in the solid-state imaging device. Therefore, since it has not only a function and effect as a simple heat-resistant protective tape by the polyimide base material but also a specific function and effect for suppressing the thermal deterioration of the color filter inside the solid-state imaging device, heating at a sufficiently high temperature of 170 ° C. or higher. The process can be performed.

  In addition to the function of improving productivity, the application of an antistatic agent can suppress the generation of static electricity when the tape is peeled off due to charging, thereby preventing the electronic device from being destroyed. In particular, by applying to the back surface of the base material, adhesion and contamination of the antistatic agent to the adherend can be reduced, and the yield can be improved.

  The present invention is the above video sensor mounting method, characterized in that at least a silicone-based material is used as an adhesive component of the adhesive tape.

  With such a configuration, it is possible to increase heat resistance and to easily control the peel adhesive strength.

  The present invention is the above-described method for mounting an image sensor, wherein the antistatic agent is mainly composed of a quaternary ammonium salt.

  As described above, it is very important to prevent the generation of static electricity in the image sensor mounting process, and in particular, an antistatic effect after passing through a high temperature is required. In addition to the general antistatic effect, the present inventor has found that an antistatic agent based on a quaternary ammonium salt is an object of the present invention under various conditions such as heat resistance and workability particularly required in the mounting process. Has been found to be a very suitable antistatic agent. As a result, the generation of static electricity when the tape is peeled can be suppressed, and the electronic device can be prevented from being destroyed.

  The present invention is the above video sensor mounting method, wherein the adhesive tape has a peeling projection on at least a part of the outer periphery thereof.

  Adhesion and peeling of the adhesive tape form an important process in the mounting of the image sensor, and it is required to reliably and later generate no deposits. In the present invention, by having a peeling protrusion on at least a part of the outer periphery, the tape can be peeled off very easily after the production process such as inspection or just before use. At this time, it is preferable that the adhesive tape does not interfere with the mounting or soldering of adjacent components in the mounted state of the video sensor.

  The present invention is the mounting method of the video sensor, wherein the adhesive tape covers the entire light receiving portion of the video sensor, and at least a part of the outer peripheral portion has a predetermined distance from the end surface of the video sensor to the center side. It is characterized by being bonded to the light receiving part.

  In order to protect the image sensor, it is necessary to have the shape of a tape that covers the entire surface of the light receiving unit. On the other hand, when the outer periphery of the tape protrudes greatly from the end surface of the image sensor, the adhesive tape is mounted on the adjacent component or This will hinder soldering. That is, the adhesive tape needs to cover the entire light receiving portion and is preferably as small as possible. Therefore, the outer peripheral portion of the adhesive tape other than the protrusions may be bonded to the light receiving portion so that at least a part thereof, preferably a large portion thereof, has a predetermined distance from the end face of the image sensor to the center side. preferable.

  The present invention is the mounting method of the video sensor, wherein the adhesive tape has a side parallel to the end face of the video sensor and connected to the terminal bottom of the protrusion, and is connected from the tip of the protrusion to the terminal bottom. The side portion has a shape of one of a diagonal line shape, a polygonal line shape, a curved line shape, or a combination thereof.

  As described above, it is preferable that the adhesive tape can be easily peeled off after the production process such as inspection or just before use. However, fixing the adhesive tape requires a predetermined adhesive strength, but if the adhesive strength is too strong, the adhesive may remain when the adhesive tape is peeled off. Limited to range. In particular, in the peeling of the adhesive tape provided with the protruding portion, the protruding portion is sandwiched and pulled up, and the adhesive tape is liable to crack at that time, and in the present invention, the leading end of the protruding portion is connected to the bottom. It has been found that the tape can be smoothly peeled off from the image sensor by having the side portion having any one of a diagonal line shape, a broken line shape, a curved line shape, or a combination thereof.

  Also, since the distance between the end face of the image sensor and the outer periphery of the light receiving unit is usually a very short distance, the mounting position of the adhesive tape is important in mounting the image sensor and is automatically applied. Even in such a case, it is necessary to confirm the pasting position. Accordingly, the adhesive tape having the side connected to the bottom end of the protrusion, which is parallel to the side forming the end face of the image sensor, can clarify the tape application position, so that it is accurate and efficient. The mounting of the video sensor can be ensured.

  The present invention is the above video sensor mounting method, wherein an adhesive layer is not provided on a portion of the adhesive tape that covers a light receiving portion of the video sensor.

  In the present invention, the adhesive tape for protecting the image sensor is intended to perform an integrated process in a state in which the adhesive tape is bonded by devising the base material and the adhesive layer, and further to the light receiving portion of the adhesive tape. By not providing the adhesive layer in the corresponding part, it has been devised that the working efficiency is increased without the adhesive remaining on the surface of the adherend when the tape is peeled after the component mounting. In other words, in the mounting process of the video sensor, in a state where an adhesive tape having a configuration in which at least a heat-resistant film is used as a base material constituting material on the light receiving part side of the video sensor and an adhesive layer is not provided on the light receiving part is bonded. By passing through a heating process at 170 ° C. or higher, it is possible to provide a mounting method for a video sensor with high workability, safety, and productivity.

Furthermore, in the mounting method of the image sensor, the thermal conductivity of the base material at 170 ° C. is 5 × 10 ⁻⁴ cal / cm · sec · ° C. or less.

  Many image sensors used as solid-state imaging devices have a built-in color filter, and often cannot withstand high temperatures during mounting. The polyimide film constituting the substrate of the pressure-sensitive adhesive tape of the present invention has low heat conductivity as well as heat resistance, and has a heat conduction suppressing effect, so that not only physical protection of the image sensor itself but also protection of the color filter Useful.

  The present invention is the above video sensor mounting method, characterized in that the heat shrinkage rate of the adhesive tape after heating at 180 ° C. for 1 hour is 1.0% or less.

  In other words, as described above, in the mounting of the image sensor, it is preferable that the shrinkage rate of the base material is small, and in particular, since it includes a process in a high temperature region such as soldering, the shrinkage rate of the base material under high temperature conditions is reduced. The knowledge that it is suitable to be in the above range has been obtained, and by clarifying such additional conditions, the working efficiency is further increased.

  The present invention is the mounting method of the image sensor, wherein the adhesive strength of the adhesive tape after heating at 180 ° C. for 1 hour is 0.1 to 8.0 N / 19 mm width. .

  That is, in order to prevent peeling of the adhesive tape, an adhesive force of a predetermined level or more is required. On the other hand, in order to prevent the adhesive layer from remaining after the tape is peeled from the adherend, it is necessary to have an adhesive force of a predetermined level or less. is there. In particular, in the case of including a mounting process in a high temperature region, it has been found that the adhesive strength of the adhesive tape under heating conditions is preferably within the above range. The work efficiency is increased without deteriorating the function of the tape and without leaving the adhesive on the surface of the adherend when the tape is peeled off after mounting the components.

  The present invention is a pressure-sensitive adhesive tape that uses a polyimide film as a constituent material of a substrate, has an adhesive layer on one side, and applies an antistatic agent on the other side. It is characterized by using.

  The mounting method described above requires an adhesive tape that protects the surface of the image sensor from contamination and scratches due to foreign matter, and that can be used without removing the tape in the component mounting process under heating conditions such as soldering. Is done. In this invention, it becomes possible to satisfy | fill such a request | requirement by providing the adhesive tape for surface protection which has the outstanding heat resistance, heat shrinkability, and adhesiveness which uses a polyimide film as a base material. In addition, it is possible to suppress the generation of static electricity when the tape is peeled off and to prevent the electronic device from being destroyed.

  As described above, according to the present invention, in the mounting process or the inspection process of the components of the solid-state imaging device, the integrated process can be performed in a state where the adhesive tape is bonded, thereby protecting the surface of the video sensor. Therefore, it is possible to provide a method for mounting a video sensor with high workability and high productivity. In addition to the function of improving productivity, the application of an antistatic agent can suppress the generation of static electricity when the tape is peeled off due to charging, thereby preventing the electronic device from being destroyed. In addition, it is possible to provide a protective adhesive tape having high heat shrinkability and excellent heat resistance that can be used when mounting such a video sensor.

  Hereinafter, embodiments of the present invention will be described.

  The mounting method of the image sensor of the present invention is a state in which an adhesive tape using a polyimide film as a constituent material of the base material is bonded to the light receiving part side of the image sensor in the mounting process of the image sensor using the solid-state imaging device. Then, the terminal portion of the video sensor is reflowed by solder connection with the substrate side. The image sensor using the solid-state imaging device here is an image sensor obtained by packaging a solid-state imaging device generally called CCD (Charge Coupled Device) or CMOS (Complementary MOS) using a transparent resin or a glass material. is there.

  The light receiving part side of the image sensor means the surface side of the sensor that receives the image, and a general image sensor may be covered with a transparent resin or a glass cover to protect the imaging device. In most cases, this includes substantially bonding the adhesive tape to the surface of these transparent resins or cover glass. Moreover, as for the surface, at least a portion corresponding to the light receiving portion may be protected, but other portions may be covered for protection.

  The pressure-sensitive adhesive tape of the present invention is basically formed from a tape base material and a pressure-sensitive adhesive layer provided on one side of the base material, but a release film may be bonded to the base material of the pressure-sensitive adhesive tape. That is, by attaching a release film having a release treatment on at least one surface to a base material of an adhesive tape via an adhesive layer, the adhesive layer can be protected and the image sensor surface can be protected. It is desirable that the adhesive tape is peeled off at any stage from the video sensor mounted in this way.

  In addition to the function of improving productivity, the application of an antistatic agent can suppress the generation of static electricity when the tape is peeled off due to charging, thereby preventing the electronic device from being destroyed.

  The antistatic agent used in the present invention is not particularly limited as long as it has an effect of suppressing the generation of static electricity when the tape is peeled off. For example, a method using a quaternary ammonium salt as a main component, a method of applying an inorganic salt or a metal compound (for example, stannic oxide) to a substrate using a dispersion medium such as water or an arbitrary organic solvent, etc. Can be mentioned. In particular, an antistatic agent mainly composed of a quaternary ammonium salt is preferable for use in the present invention because of its ease of handling such as solubility in a solvent and solvent coating property.

  In view of the application of the present invention, in view of transfer / contamination of the additive component to the solid-state imaging device as the adherend, it is preferable to perform the treatment on the back side of the substrate. Moreover, when it provides in the surface of an adhesion layer, there exists a possibility of affecting the mutual characteristic of an adhesion layer and an antistatic agent, and it is unpreferable.

  At this time, it is preferable to have a protrusion for peeling on at least a part of the outer periphery of the adhesive tape. Specifically, as illustrated in FIG. 1, in a state where the adhesive tape 3 is bonded to the light receiving portion 2 of the video sensor 1, the protruding portion 3 a protrudes from the end surface 1 a of the video sensor 1 to a part of the adhesive tape 3. It has a form like this. In such a form, the video sensor 1 is attached to the board, and after passing through high-temperature solder reflow and mounting processing, the operation of the video sensor 1 or the function of the mounting board is inspected. The adhesive tape 3 can be peeled off very easily automatically or manually after the production process is completed or immediately before use.

  It is preferable that a part of the outer peripheral part of the adhesive tape 3 is attached between the end face of the image sensor 1 and the light receiving part 2. That is, the width of the adhesive tape 3 is preferably larger than the width of the light receiving unit 2 and smaller than the width of the image sensor 1. Furthermore, as shown in FIG. 1, it is preferable that the outer peripheral portion of the adhesive tape 3 except the side portion 1 b of the video sensor 1 covered by the protruding portion 3 a is intermediate between the end face of the video sensor 1 and the light receiving portion 2. . The light receiving unit 2 can be covered entirely with the adhesive tape 3, and the cover of the adhesive tape on the peripheral members can be prevented when the image sensor 1 is mounted. However, in the mounted state of the image sensor 1 such as the substrate, when there is a space around the substrate that does not require other mounting and does not require soldering, a part of the outer peripheral portion is the end surface of the image sensor 1 and the light receiving portion. It is sufficient if it is in the middle of 2 and is not necessarily required for the entire circumference.

  Moreover, the shape of the adhesive tape 3 is illustrated in FIG. As shown in FIG. 2A, there are a case where a protrusion 3a is provided on one side of a substantially square, a substantially rectangular shape as shown in FIG. 2B, or a shape that matches the shape of the video sensor 1.

  The shape of the protrusion 3a is not particularly limited, but a shape that can be clamped regardless of whether it is automatic or manual is preferable. Further, a shape that can be easily processed is preferable. For example, squares such as those shown in FIGS. 2A and 2B can be cited, but a semicircular shape, a trapezoidal shape as illustrated in FIG. 2C, or a shape illustrated in FIG. A shape such as a combination of a square and a trapezoid is also possible.

  At this time, the vicinity of the protruding portion 3a is connected to the bottom of the protruding portion 3a so as to be parallel to the end surface 1a of the image sensor 1 as shown in FIG. 1, more precisely, the side portion 1b constituting the end surface 1a. It is preferable to have the side 3b. A clear pasting position can be secured, and confirmation of adhesion becomes easy. In addition, when the image sensor 1 is not a square as illustrated in FIG. 1 but a square shape without an angular portion, an oval shape, or an oval shape, the image sensor 1 has a similar shape parallel to the side portion constituting the end face. It is preferable to have a side part.

  Furthermore, in the protrusion 3a, it is preferable that the side part 3c connected from the front-end | tip 3d to a terminal bottom has any shape of diagonal line shape, broken line shape, curve shape, or these combination. When the pressure-sensitive adhesive tape 3 is peeled off, the strongest force acts on the center line of the protrusion 3a. Therefore, in the shape 3e as shown by the broken line in FIG. There is a risk of causing the adhesive to remain in No. 2. Therefore, it is preferable that the side portion 3c has a shape that can achieve the dispersion of force during peeling. The specific shape is not particularly limited as long as it has a force distribution function, and examples thereof include the shape of the side portion 3c as shown in FIGS. That is, the shape of the side portion 3c is a slanted line shape (FIG. 2C), a broken line shape (FIG. 2D), a curved line shape (FIGS. 2A and 2B), or a combination thereof (not shown). ), The side portion 3c can be smoothly peeled off when the pressure-sensitive adhesive tape 3 is peeled off. Accordingly, the entire protrusion 3a can be peeled off with a substantially uniform force, and the main part of the tape covering the light receiving portion 2 is peeled off with a substantially uniform force in the in-plane vertical direction of the peeling direction X. Can do. The inclination angle of the oblique line or the broken line, the curvature of the curve, and the like can be arbitrarily set depending on the shape of the video sensor 1, the entire adhesive tape 3, the shape of the protruding portion 3a, and the like.

  Moreover, it is preferable that an adhesive tape does not provide an adhesive layer in the part applied to the light-receiving part of a video sensor. This is because the pressure-sensitive adhesive does not remain on the surface of the adherend when the tape is peeled after component mounting, and the work efficiency is increased.

  Specifically, as illustrated in FIG. 3, when the adhesive layer 5 is formed on the base material 4, an uncoated portion having a width a is formed at a portion of the adhesive tape that covers the light receiving portion of the video sensor. In addition, a method of forming a pressure-sensitive adhesive layer 5 having a width b at both ends and producing a pressure-sensitive adhesive tape can be exemplified. However, the shape of the adhesive layer 5 is not particularly limited as long as an uncoated portion can be formed in a portion that is applied to the light receiving portion of the image sensor. For example, as illustrated in FIG. A) a method of providing a hollow shape of an arbitrary shape such as a circular shape, (B) a square shape, (C) a method of forming the adhesive layer 5 at the four corners of the base material 4, and (D) a slanted shape having a predetermined width. Various methods such as a method of forming a coated portion can be applied. The shaded part in FIG. 4 shows the adhesive application part.

  By the above method, the adhesive layer 5 is formed so as not to be biased with respect to the surface of the image sensor and to secure a coating area, thereby ensuring the sufficient adhesion strength to the surface of the image sensor and affecting the light receiving portion. Can be prevented.

  As an adhesive tape to be bonded to these, it is necessary to use a polyimide film as a constituent material of the substrate. By forming an adhesive tape for surface protection that has excellent heat resistance, heat shrinkability, and adhesiveness, it is possible to work without peeling the tape in the component mounting process under heating conditions. is there.

  The polyimide film here is not particularly limited, but it is desirable that the polyimide film has a certain thickness in order to sufficiently exhibit the rigidity as a tape and the brown shading effect of the polyimide film. Specifically, the thickness may be 10 μm or more, more preferably 20 μm or more.

  The base material may be a polyimide film alone, but may be a base material having at least one polyimide film layer and laminated, or a film containing a polyimide material as a raw material. Moreover, arbitrary surface treatment, extending | stretching treatment, or a plasticizer and an additive may be contained.

However, in order to have a sufficient effect of suppressing heat conduction to the color filter, it is desirable that the substrate has a heat conductivity of, for example, 170 ° C. of 5 × 10 ⁻⁴ cal / cm · sec · ° C. or less. Polyimide film has low heat conductivity as well as heat resistance, and in addition to physical protection of the image sensor itself, it is possible to protect the color filter against high temperatures during mounting.

  In addition, although the material of an adhesive etc. is not specifically limited, Acrylic adhesive or a silicone adhesive etc. are mentioned specifically ,. In particular, silicone adhesives are not only excellent in heat resistance, but also easy to adjust the adhesive strength, so by arbitrarily adjusting the adhesive strength when peeling the tape after the mounting is finally completed, It is possible to design an adhesive tape excellent in handling, and it can be said that it is a particularly suitable adhesive material.

  Further, the present invention is characterized in that the terminal portion of the image sensor is soldered and reflowed to the substrate side by heating to 170 ° C. or higher. This indicates mounting by solder bonding using a reflow furnace. Specifically, it is only necessary that the maximum temperature during processing in the reflow furnace exceeds 170 ° C.

  The thickness of the adhesive layer of the adhesive tape is 1 μm or more and 100 μm or less, preferably 3 μm or more and 50 μm or less, more preferably 5 μm or more and 30 μm or less. In order to secure the adhesive layer, it is effective if even a slight level difference is generated on the surface of the base material. Also decreases. Further, the adhesive tape may be peeled off due to heat shrinkage of the film being heated. If the thickness exceeds 100 μm, the adhesive will be deformed during slitting and punching of the tape, or the adhesive will be deformed by pressure applied to the tape, pressure applied to the tape during transportation, and heating during mounting. This may cause the adhesive to be applied to the light receiving portion.

  In other words, in order to protect the image sensor, it is necessary to have a predetermined mounting strength as an adhesive tape, and it is necessary to maintain a bonded state in harmony with the image sensor, and workability is also in demand. Accordingly, the pressure-sensitive adhesive tape of the present invention has been found that the above range is the optimum range as a result of actual measurement. Therefore, it is possible to provide a video sensor mounting method with high workability, safety, and productivity by using an adhesive tape having such a thickness of the adhesive layer.

  Furthermore, in the present invention, the heat shrinkage rate of the adhesive tape after heating at 180 ° C. for 1 hour is 1.0% or less, more preferably 0.5% or less, and further preferably 0.3% or less. It is desirable. This is to further improve the working efficiency by clarifying additional conditions regarding the shrinkage ratio of the base material under high temperature conditions. The heat shrinkage referred to here is based on the value after bonding to a BA plate in the form of an adhesive tape and leaving it at 180 ° C. for 1 hour. Specifically, the heat shrinkage rate is measured by cutting an adhesive tape into 20 mm square, sticking it to a BA plate, heating it at a temperature of 180 ° C., and measuring the size of the tape before and after the heating by a projector (Mitutoyo: Both MD direction and TD direction were measured using PROFILE PROJECTOR PJ-H3000F). The BA plate refers to a SUS304 plate (BA5 finish SUS304 manufactured by Nippon Metal Co., Ltd.) surface-finished to BA5 in accordance with JIS “BA finish”.

  Moreover, in this invention, it is preferable that the adhesive force of the adhesive tape after implementing a heating at 180 degreeC for 1 hour is 0.1-8.0N / 19mm width, Moreover, 0.2N-5.0N / A width of 19 mm is more preferable, and a width of 0.3 N to 4.0 N / 19 mm is even more preferable. When the adhesive strength exceeds 8.0 N / 19 mm, it is difficult to remove the tape from the adherend in the process, and the adhesive layer may remain on the adherend surface. This is because the adhesive tape may peel off due to heat shrinkage. The adhesive force here is based on a value measured according to JIS Z0237.

  Moreover, when using a release film for an adhesive tape, you may use any well-known thing as a release film. Specifically, a release coating layer, for example, a silicone layer formed on the bonding surface of the release film with the adhesive layer of the base material can be used. Examples of the substrate for the release film include paper materials such as glassine paper and resin films made of polyethylene, polypropylene, polyester, and the like.

  Moreover, this adhesive tape may be processed according to the use, for example, the size of the target solid-state imaging device. The processing method is not particularly limited as long as it is a method that maintains a uniform shape and does not leave a pressure-sensitive adhesive in the processed cross section, but punching is preferable in view of productivity.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below. Moreover, the evaluation method in an Example etc. was performed as follows. In addition, it cannot be overemphasized that this invention is not limited to this Example and evaluation method.

<Evaluation method>
About the tape produced on the said conditions, the following item was evaluated.
(1) Shape of the tape after heating The shape of the tape after the samples of the above-mentioned Examples and Comparative Examples were bonded to the glass surface and left for 1 hour at a temperature of 180 ° C.
(2) The state of the glass surface after tape peeling The state of the glass surface after tape peeling was confirmed visually.
(3) Amount of discharge After the adhesive surface of the tape was bonded to the glass surface, the amount of discharge when the adhesive tape was peeled off after standing for 30 minutes was measured. The discharge amount was measured as follows.
(3-1) A coaxial cable is connected to the upper part of the tip peel surface of the high speed peel tester and installed so as to move at the same speed with respect to the peel surface.
(3-2) Further, by connecting a coaxial cable to an oscilloscope, the value of electromagnetic waves generated at the time of peeling was measured.
(3-3) Each adhesive tape is cut into a width of 20 mm, affixed to a glass surface, and set in the apparatus.
(3-4) Then, the value of the electromagnetic wave observed when measured at a peeling angle of 180 ° and a peeling speed of 5 mm / min is defined as a discharge value.
(3-5) The measured maximum value of the electromagnetic wave peak is defined as the discharge value. In addition, the determination of whether the discharge is good or bad is based on a discharge amount of 100 mV, with 100 mV or less being good and a case where it exceeds 100 mV being regarded as bad.
(4) Peelability After pasting samples of the following examples and comparative examples on the surface glass of the CCD package, the maximum temperature was 180 ° C. × 5 seconds (the reflow furnace was charged for about 90 seconds including residual heat) Easiness of peeling after putting it in the solder reflow oven and mounting it on the board.

<Example 1>
Polyimide film (Kapton 100H manufactured by Toray DuPont Co., Ltd .: thickness 25 μm, thermal conductivity at 170 ° C. is about 4.1 × 10 ⁻⁴ cal / cm · sec · ° C.) and silicone adhesive (SD manufactured by Toray Dow Corning) -4580) was applied to a thickness of 10 μm, and bonded to the surface glass of the CCD package. This was put in a solder reflow furnace having a maximum temperature of 180 ° C. × 5 seconds (the reflow furnace was charged for about 90 seconds including preheating) and mounted on the substrate. Note that the tape was peeled off after mounting was completed.
As a result, the surface after peeling the tape was not confirmed such as scratches or adhering foreign matter, and normal operation as a CCD was confirmed.

<Example 2>
A quaternary ammonium salt (NR-121X manufactured by Colcoat Co., Ltd.) is applied on the back side of the base material of the adhesive tape on a base material made of polyimide having a thickness of 25 μm (Kapton 100H manufactured by Toray Du Pont). Thereafter, an acrylic adhesive solution was applied to the opposite surface and dried to prepare an adhesive tape having an adhesive layer having a thickness of 10 μm.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.5 N / 19 mm, and the heat shrinkage rate was 0.1%. Moreover, peeling of the tape was not confirmed, and the maximum value of the discharge amount was 50 mV.

<Example 3>
As shown in FIG. 2A described above, the adhesive tape is a tape having a protruding portion with a protruding length of 4 mm from a covered portion of 11 mm × 12 mm square, passing through an arc-shaped side portion of R = 2 (mm). An adhesive tape similar to that of Example 1 was produced except that the shape was changed. This tape was attached to the surface glass of the CCD package, and was put into a 180 ° C. solder reflow furnace in the same manner as in Example 1 and mounted on the substrate.
Thereafter, when the tape was peeled off from the protruding portion of the tape, it could be easily peeled off from the protruding portion without breaking the tape. The surface of the CCD package after the tape was peeled was not confirmed to be scratched or adhered foreign matter, and normal operation as a CCD was confirmed.

<Example 4>
As shown in FIG. 2 (C) described above, the adhesive tape is opened from the 6 mm × 7 mm square covering portion by 1 mm to the outer sides of both ends (3b and 3f in FIG. 2 (C) are 1 mm). A pressure-sensitive adhesive tape similar to that of Example 2 was produced, except that a tape-like shape having a protruding portion with a protrusion length of 2.5 mm was passed through the inclined side portion. This tape was attached to the surface glass of the CCD package, and was put into a 180 ° C. solder reflow furnace in the same manner as in Example 1 and mounted on the substrate.
Thereafter, when the tape was peeled off from the protruding portion of the tape, it could be easily peeled off from the protruding portion without breaking the tape. The surface of the CCD package after the tape was peeled was not confirmed to be scratched or adhered foreign matter, and normal operation as a CCD was confirmed.

<Comparative Example 1>
A nylon film having a thickness of 25 μm (6 nylon manufactured by Toray Industries Inc .: thermal conductivity of about 5.5 × 10 ⁻⁴ cal / cm · sec · ° C.) and a storage elastic modulus of 2.0 × 10 ³ N / cm ² The same procedure as in Example 1 was performed except that a pressure-sensitive adhesive tape coated with a rubber pressure-sensitive adhesive having a thickness of 10 μm was used.
As a result, a position shift occurred in the bonded portion due to heat shrinkage of the tape, and the heat-degraded adhesive remained on the peeled surface and was contaminated. Also, the CCD itself did not operate normally because the color filter inside the CCD was damaged due to the reflow temperature.

<Comparative example 2>
An adhesive tape produced in the same manner as in Example 2 was obtained except that the quaternary ammonium salt was not applied to the adhesive tape.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.5 N / 19 mm, and the heat shrinkage rate was 0.1%. Moreover, although peeling of a tape was not confirmed, discharge of 400 mV was confirmed.

<Comparative Example 3>
An adhesive tape produced in the same manner as in Example 2 was obtained except that a quaternary ammonium salt was applied to the back surface of the adhesive layer of the adhesive tape.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.5 N / 19 mm, and the heat shrinkage rate was 0.1%. Further, no peeling of the tape was confirmed, but a discharge of 350 mV was confirmed.

<Comparative example 4>
An adhesive tape similar to that of Example 4 was produced, except that the side portion of the protrusion had a right-angled terminal shape (shape 3e as shown by the broken line in FIG. 2A). This tape was attached to the surface glass of the CCD package, and was put into a 180 ° C. solder reflow furnace in the same manner as in Example 1 and mounted on the substrate.
Thereafter, when the tape was peeled off from the protruding portion of the tape, a crack was generated from the corner portion at the bottom of the protruding portion, the tape was cut, and the entire tape could not be easily peeled off from the protruding portion.

<Reference Example 1-1>
A quaternary ammonium salt (NR-121X manufactured by Colcoat Co., Ltd.) is applied to the back side of the base material of the adhesive tape on a base material made of polyethylene naphthalate having a thickness of 25 μm. Thereafter, an acrylic adhesive solution was applied to the opposite surface and dried to prepare an adhesive tape having an adhesive layer having a thickness of 10 μm.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.0 N / 19 mm, the thermal shrinkage was 0.15%, and the adhesive tape was measured at 500 nm. The transmittance was 86.0%. Moreover, peeling of the tape was not confirmed, and the maximum value of the discharge amount was 50 mV.

<Reference Example 1-2>
A pressure-sensitive adhesive tape produced by the same method as in Reference Example 1-1 was obtained except that a quaternary ammonium salt was applied to the back surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.0 N / 19 mm, the thermal shrinkage was 0.15%, and the adhesive tape at 500 nm. The light transmittance was 88.0%. Moreover, although peeling of a tape was not confirmed, discharge of 400 mV was confirmed.

<Reference Example 1-3>
A pressure-sensitive adhesive tape produced by the same method as in Reference Example 1-1 was obtained except that polyethylene terephthalate (Lumirror S-10 # 38 manufactured by Toray Industries, Inc.) was used as a base material used for the pressure-sensitive adhesive tape. After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 1.5 N / 19 mm, the heat shrinkage rate was 1.3%, and the adhesive tape was measured at 500 nm. The light transmittance was 90.0%. Moreover, although the maximum value of the discharge amount was 50 mV, lifting of the end face of the adhesive tape was confirmed.

<Reference Example 2-1>
On a base material made of polyethylene naphthalate having a thickness of 2 μm, an acrylic adhesive solution is applied in a stripe shape alternately with a 10 mm wide coated part and a 10 mm wide uncoated part, and dried to a thickness of 5 μm. An adhesive tape having an adhesive layer was prepared. The pressure-sensitive adhesive tape was slit with a width of 20 mm so that the uncoated portion was at the center of the tape to obtain a pressure-sensitive adhesive tape. The adhesive tape has a = 10 mm and b = 5 mm in FIG.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 1.0 N / 19 mm and the thermal shrinkage was 0.15%. The shape of the tape after heating was not confirmed to float or peel from the glass surface of the tape.

<Reference Example 2-2>
A pressure-sensitive adhesive tape produced in the same manner as in Reference Example 2-1 was obtained except that the acrylic pressure-sensitive adhesive solution was not applied in a stripe shape.
After the adhesive tape was heated at 180 ° C. for about 1 hour, the adhesive strength measured according to JIS Z0237 was 2.0 N / 19 mm, and the thermal shrinkage was 0.15%. As for the tape after a heating, the foreign material derived from an adhesive was confirmed on the glass surface after tape peeling.

<Summary of results>
From the above results, it was possible to provide a surface protective pressure-sensitive adhesive tape used in molding a CCD package having excellent heat resistance, workability, and peelability while suppressing discharge during peeling.

Explanatory drawing which shows the bonding state to the video sensor of the adhesive tape which concerns on this invention. Explanatory drawing which illustrates the shape of the adhesive tape which concerns on this invention. Explanatory drawing which shows the fundamental structure of the adhesive tape which has an adhesive non-application part of this invention. Explanatory drawing which shows the other structure of the adhesive tape which has an adhesive non-application part in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image sensor 2 Light-receiving part 3 Adhesive tape 3a Protrusion part 3b Side part 3c Side part 3d Tip 4 Base material 5 Adhesive layer X Center line

Claims (11)

  In the mounting process of a video sensor using a solid-state imaging device, a polyimide film is used as a constituent material of the base material on the light receiving part side of the video sensor, an adhesive layer is provided on one side, and an antistatic agent is applied on the other side. A method of mounting a video sensor, characterized in that the terminal portion of the video sensor is soldered and reflowed to the substrate side by heating to 170 ° C. or higher with the adhesive tape attached.   The video sensor mounting method according to claim 1, wherein at least a silicone-based material is used as an adhesive component of the adhesive tape.   The video sensor mounting method according to claim 1, wherein the antistatic agent is mainly composed of a quaternary ammonium salt.   The mounting method of the image sensor according to claim 1, wherein the adhesive tape has a peeling protrusion on at least a part of the outer periphery thereof.   The adhesive tape covers the entire light receiving part of the video sensor, and is bonded to the light receiving part so that at least a part of the outer peripheral part has a predetermined distance from the end surface of the video sensor to the center side. The mounting method of the video sensor according to claim 1.   The adhesive tape has a side parallel to the end face of the image sensor and connected to the terminal bottom of the protrusion, and the side connected from the tip of the protrusion to the terminal bottom is an oblique line, a polygonal line, a curve, or these The video sensor mounting method according to claim 1, wherein the video sensor has a shape of any one of the combinations.   The video sensor mounting method according to claim 1, wherein an adhesive layer is not provided on a portion of the adhesive tape that covers the light receiving portion of the video sensor. The method of mounting a video sensor according to claim 1, wherein the substrate has a thermal conductivity of 5 × 10 ⁻⁴ cal / cm · sec · ° C. or lower at 170 ° C.   The method for mounting a video sensor according to claim 1, wherein a heat shrinkage rate of the adhesive tape after heating at 180 ° C. for 1 hour is 1.0% or less.   10. The video sensor mounting according to claim 1, wherein the adhesive strength of the adhesive tape after heating at 180 [deg.] C. for 1 hour is 0.1 to 8.0 N / 19 mm width. Method. The mounting of a video sensor according to any one of claims 1 to 10, wherein a polyimide film is used as a constituent material of the substrate, has an adhesive layer on one side, and is coated with an antistatic agent on the other side. An adhesive tape characterized by being used in a method.

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