JP5363894B2 - Component mounting method - Google Patents

Description

  The present invention relates to a component mounting method for mounting a component such as a semiconductor chip on a substrate.

  Conventionally, as a method for mounting a component such as a semiconductor chip on a printed wiring board or the like, there is a component mounting method in which a bump formed on one of the component and the substrate is bonded to an electrode formed on the other (for example, (See Patent Document 1 and Patent Document 2.)

  FIG. 10 is an explanatory diagram for explaining a state in which components are mounted by the conventional component mounting methods of Patent Document 1 and Patent Document 2.

  In the conventional component mounting method, when the component 90 is mounted on the substrate 80 on which the bumps 81 and 82 as shown in FIG. The head 70 is moved in a direction along the substrate 80 so that the component 90 is opposed to a portion of the substrate 80 where the component 90 is to be mounted.

  Next, when the head 70 is lowered and it is detected that the electrode 91 of the component 90 is in contact with either of the bumps 81 and 82, a predetermined load is applied to the head 70 as shown in FIG. The head 70 is further lowered from the height of the head 70 at the time of detection. Further, in order to finally join the bumps 81 and 82 to the electrode 91, ultrasonic vibration is applied to the electrode 91 and the bumps 81 and 82.

JP 2000-195907 A JP-A-11-345835

  However, the conventional component mounting method has a problem in that the bumps 81 and 82 and the electrode 91 may not be sufficiently bonded to each other because a predetermined load is applied to the head 70 to lower the head 70. That is, as shown in FIG. 10A, when the bumps 81 and 82 have different heights, the head 70 stops without further lowering than the state shown in FIG. 10B. As a result, the bump 82 and the electrode 91 may not be joined. Even if the bump 82 is bonded to the electrode 91, the bonding strength may be insufficient.

  Therefore, the present invention has been made in view of such problems, and an object thereof is to provide a component mounting method that improves the bonding quality between a component and a board.

To achieve the above object, the component mounting method according to the present invention, the bumps formed on the substrate, so as to come into contact with the electrode formed on the component, the component mounting for mounting a plurality of parts before SL on the substrate a method, a bump information reading step of reading a bump information indicating a form of a plurality of bumps formed on the substrate from the storage unit, based on the bumps information read by said bump information reading process, is bonded to the substrate Bump bonding height such that the bonding area when the bumps corresponding to a plurality of components and the electrodes are bonded is equal to or greater than a predetermined area, and is specified for each bump formed on the substrate a bump bonding height specifying step of specifying the lowest bump bonding height of the height, a position detection step of detecting a position of a plurality of bumps in the substrate, in the position detection step Ri for each detected position, so that the parts of the electrodes facing the position, a placement step of placing the substrate and the component, the height of the bumps to be bonded object formed on the substrate, wherein A pressing step of pressing either one of the substrate and the component against the other while maintaining the state of being arranged in the arrangement step so as to be the lowest bump bonding height specified by the bump bonding height specifying step, And an ultrasonic bonding step of bonding the bump and the electrode by applying ultrasonic vibration.

  As a result, even if the position of the bump formed on the bump forming body is shifted from the position where it should be, the position of the bump formed on the bump forming body is detected, and the electrode is placed at the detected position. Since the bump formed body and the electrode formed body are arranged so as to face each other, the bump can be reliably bonded to the electrode without the bump being displaced from the electrode. In addition, when a plurality of electrodes are densely formed on the electrode forming body, it is possible to prevent a short circuit from occurring due to the deviation of the bumps after mounting.

  The present invention can also be realized as a component mounting apparatus or a component mounting system for mounting components by the above-described component mounting method.

  The component mounting method of the present invention has the effect of improving the bonding quality between the component and the board.

It is a block diagram which shows the external appearance structure of the component mounting system which mounts components, such as a semiconductor chip, on a board | substrate by the component mounting method in embodiment of this invention. It is a block diagram which shows the internal structure of a bump test | inspection apparatus and component mounting apparatus same as the above. It is explanatory drawing for demonstrating a mode that the position detection part of a bump inspection apparatus same as the above detects a bump position. It is explanatory drawing for demonstrating a mode that the form detection part of a bump test | inspection apparatus same as the above detects a bump form. It is an information content display figure which shows the content of bump information same as the above. It is explanatory drawing for demonstrating the effect of the component mounting method same as the above compared with the conventional case. It is a figure which shows bump bonding height which the control part same as the above specifies. It is explanatory drawing for demonstrating a mode that components are mounted by the component mounting system same as the above. It is a flowchart which shows operation | movement of a component mounting system same as the above. It is explanatory drawing for demonstrating a mode that components are mounted by the conventional component mounting method.

  Hereinafter, a component mounting method according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram showing an external configuration of a component mounting system that mounts a component such as a semiconductor chip on a substrate by the component mounting method according to the present embodiment.

  Such a component mounting system improves the bonding quality between the component and the substrate, and inspects the bump b formed on the substrate 10 and generates the bump information 104a related to the bump b. And a component mounting apparatus 200 that mounts components on the substrate 10 based on the bump information 104a generated by the bump inspection apparatus 100.

  The bump inspection apparatus 100 inspects the bump b using, for example, an optical device such as a laser or a microscope, and generates the above-described bump information 104a as the inspection result. The bump information 104a indicates the position of the bump b formed on the substrate 10 (hereinafter referred to as bump position) and the form of the bump (hereinafter referred to as bump form). The bump form indicates the height of the bump b, Including width.

  The component mounting apparatus 200 includes a head 201 that attracts components and a head drive mechanism 202 that drives the head 201, and the head drive mechanism 202 is based on the bump information 104 a generated by the bump inspection apparatus 100. Drive.

  FIG. 2 is a block diagram showing the internal configuration of the bump inspection apparatus 100 and the component mounting apparatus 200.

  The bump inspection apparatus 100 includes a position detection unit 101 that detects a bump position, a form detection unit 102 that detects a bump form, a storage unit 104 having an area for storing bump information 104a, a position detection unit 101, and a form. A writing unit 103 that generates bump information 104 a from the bump position and bump form detected by the detection unit 102 and writes the bump information 104 a in the storage unit 104 is provided.

  The component mounting apparatus 200 is based on the reading unit 203 that reads the bump information 104a from the storage unit 104 of the bump inspection apparatus 100, the head 201 and the head driving mechanism 202, and the bump information 104a read by the reading unit 203. And a control unit 204 that controls the head driving mechanism 202. The head 201 adsorbs the component 20 with the surface on which the electrode of the component 20 to be mounted is formed facing the substrate 10, and the direction along the substrate 10 according to the operation of the head drive mechanism 202. And move in a direction perpendicular to the substrate 10.

  FIG. 3 is an explanatory diagram for explaining how the position detection unit 101 of the bump inspection apparatus 100 detects a bump position.

  The position detection unit 101 detects the coordinate position (x, y) of the bumps b1 and b2 formed on the substrate 10 as the bump position with reference to the origin 0 specified from the substrate mark 11 formed on the substrate 10. For example, the position detection unit 101 detects the coordinate position (x1, y1) as the bump position of the bump b1.

  FIG. 4 is an explanatory diagram for explaining a state in which the form detection unit 102 of the bump inspection apparatus 100 detects a bump form.

  The bump b is made of, for example, gold and has a pedestal ba and a crushing margin bb. The form detection unit 102 specifies the height (h) of the entire bump including the base ba and the crushing margin bb and the width (w) of the portion of the crushing bb that contacts the base ba. In general, the diameter of the base ba of the bump b is about 80 μm, and the height (h) is 60 to 70 μm.

FIG. 5 is an information contents display diagram showing the contents of the bump information 104a.
The writing unit 103 determines the coordinate position (x, y) that is the bump position detected by the position detection unit 101 and the height (h) and width (w) that are the bump form detected by the form detection unit 102. The bump information 104a is generated in association with the corresponding bump b, and the bump information 104a is written in the storage unit 104.

  The control unit 204 of the component mounting apparatus 200 acquires the coordinate position (x, y) of the bump b corresponding to the component 20 to be mounted from the bump information 104a, and uses the origin 0 indicated by the substrate mark 11 of the substrate 10 as a reference. The part on the substrate 10 indicated by the coordinate position (x, y) is specified.

  Then, the control unit 204 controls the head driving mechanism 202 to move the head 201 that sucks the component 20 in the direction along the substrate 10, so that the component 20 with respect to the part on the substrate 10 specified as described above. The electrodes are opposed to each other.

  That is, since the coordinate position (x, y) indicated by the bump information 104a indicates the bump position of the substrate 10, when the head 201 moves as described above, the electrode of the component 20 and the substrate 10 corresponding thereto. The upper bump b is in a state of facing.

  Here, also when one component 20 is joined by a plurality of bumps b, as described above, the control unit 204 bumps the coordinate positions (x, y) of the plurality of bumps b corresponding to the component 20 to be mounted. The site | part on the board | substrate 10 which is acquired from the information 104a and each of those coordinate positions (x, y) shows is specified. And the control part 204 opposes the electrode of the component 20 corresponding to each of the specified some site | part.

  Further, the control unit 204 controls the head driving mechanism 202 to lower the head 201 in a direction perpendicular to the substrate 10 and place the component 20 on the substrate 10.

  As described above, in the present embodiment, the bump position on the substrate 10 is detected in advance, and the component 20 is mounted so as to match the position, so that the bump b is not displaced from the electrode of the component 20. The bump b can be reliably bonded to the electrode. Moreover, the occurrence of a short circuit due to the mounting of the component 20 can also be prevented.

  That is, conventionally, in order to align the component 20 with the mounting site where the component 20 on the substrate 10 is to be mounted regardless of the bump position on the substrate 10, the bump b of the substrate 10 is formed so as to be shifted from the original position. In such a case, a short circuit may occur due to the mounting of the component 20.

  FIG. 6 is an explanatory diagram for explaining the effect of the present embodiment in comparison with the conventional case.

  For example, as shown in FIG. 6A, three bumps b1, b2, and b3 are formed on the P pole 12 on the substrate 10 so as to be shifted from the positions b11, b12, and b13 that should be originally formed. There may be a case where one bump b4 is formed on the N pole 13 so as to be shifted from the position b14 where it should be.

  In such a case, in the conventional component mounting apparatus, the component 20 is placed on the substrate 10 so that the center 14 of the mounting site specified from the individual mark on the substrate 10 is the center of the component 20. As a result, as shown in FIG. 6B, the P pole 21 and the N pole 22 (electrode 23) of the component 20 are in contact with each other through the bump b4 of the substrate 10. In particular, when the component 20 is an LED (Light Emitting Diode), the gap between the P-pole 21 and the N-pole 22 is narrow, and there is a high probability that such contact will occur.

  However, in the present embodiment, the bump positions of the bumps b1 to b4 on the substrate 10 are detected in advance, the P pole 21 of the component 20 faces the bump positions of the bumps b1 to b3, and the bump position of the bump b4. Since the component 20 is placed on the substrate 10 so that the N poles 22 of the component 20 face each other, even if the positions of the bumps b1 to b4 are shifted, as shown in FIG. The 20 P-poles 21 and N-poles 22 can be maintained in a non-contact state. Further, in the present embodiment, since the alignment by the center 14 is not required as in the conventional example, the step of recognizing the individual mark can be omitted and the mounting time of the component 20 can be shortened.

  In addition, the control unit 204 of the present embodiment determines the bump b and the electrode 23 of the component 20 based on the height (h) and width (w) of the bump information 104a read from the storage unit 104 by the reading unit 203. The bump bonding height of the bump b is specified such that the bonding area when the is bonded becomes a predetermined area or more. Then, the control unit 204 lowers the head 201 that adsorbs the component 20 and presses the component 20 toward the substrate 10 until the height (h) of the bump b to be bonded becomes the bump bonding height. Crush bump b.

FIG. 7 is a diagram illustrating the bump bonding height specified by the control unit 204.
For example, in the case where one component 20 is bonded only to the bump b1, only when the bump b1 is bonded to the electrode 23 of the component 20, the control unit 204 has a bump bonding that has a predetermined bonding area or more. The height hb1 is specified based on the height (h1) and the width (w1) of the bump b1 indicated by the bump information 104a.

  In addition, when one component is bonded to the bump b1 and the bump b2, the control unit 204 has a bonding area larger than a predetermined size when the bump b1 and the bump b2 are bonded to the electrode 23 of the component 20, respectively. Is determined based on the height (h1) and width (w1) of the bump b1 indicated by the bump information 104a, and the height (h2) and width (w2) of the bump b2. To do.

  That is, since the height (h2) of the bump b2 is lower than the height (h1) of the bump b1, the control unit 204 uses the bump b2 as a reference to perform bump bonding so that the bump b2 is bonded with a predetermined bonding area or more. The height hb2 is specified. As a result, the bump bonding height hb2 is lower than the bump bonding height hb1.

  Further, when one component 20 is bonded to the bump b1, the bump b2, and the bump b3, the control unit 204, when the bump b1, the bump b2, and the bump b3 are bonded to the electrode 23 of the component 20, respectively. The bump bonding height hb3, which has a bonding area greater than or equal to a predetermined value, is selected from the height (h1) and width (w1) of the bump b1 indicated by the bump information 104a, and the height (h2) and width ( It is specified based on w2) and the height (h3) and width (w3) of the bump b3.

  That is, since the width (w3) of the bump b3 is smaller than the width (w2) of the bump b2 and the width (w1) of the bump b1, the control unit 204 uses the bump b3 as a reference and the bump b3 has a predetermined bonding area or more. The bump bonding height hb3 is specified. As a result, the bump bonding height hb3 is lower than the bump bonding height hb2.

  FIG. 8 is an explanatory diagram for explaining a state in which the component 20 is mounted by the component mounting system of the present embodiment.

  The control unit 204 specifies the bump bonding height hb2 as described above even when the heights of the bumps b1 and b2 formed on the substrate 10 are different as shown in FIG. Then, as shown in FIG. 8B, the control unit 204 causes the head drive mechanism 202 to move the head in a state where the electrode 23 (P pole 21 or N pole 22) of the component 20 is opposed to the bumps b1 and b2. 201 is lowered, the component 20 sucked by the head 201 is pressed against the substrate 10, and the bumps b1 and b2 are crushed until the height of the bumps b1 and b2 reaches the bump bonding height hb2.

  The component mounting apparatus 200 ultrasonically bonds the bumps b1 and b2 and the electrode 23 by applying ultrasonic vibration.

  As described above, in this embodiment, the bump bonding height is specified based on the form of the bump b on the substrate 10, and the component 20 is pressed against the substrate 10 until the height of the bump b becomes the bump bonding height. Since the bumps b are crushed, the bumps b can be bonded to the electrodes 23 of the component 20 with a bonding area of a predetermined area or more. That is, the bump b and the electrode 23 of the component 20 can be reliably bonded with a bonding strength of a predetermined amount or more, and occurrence of bonding failure can be prevented. Even if the height of the plurality of bumps b on the substrate 10 varies, each bump b and the electrode 23 of the component 20 corresponding to each bump b can be reliably bonded with a bonding strength of a predetermined amount or more. .

FIG. 9 is a flowchart showing the operation of the component mounting system in the present embodiment.
First, the position detection unit 101 and the form detection unit 102 of the bump inspection apparatus 100 detect the bump position and the bump form (step S100). The writing unit 103 generates bump information 104a from the bump position and bump form detected in step S100 and writes the bump information 104a to the storage unit 104 (step S102).

  Next, the reading unit 203 of the component mounting apparatus 200 reads the bump information 104a from the storage unit 104 (step S104). The control unit 204 specifies a part on the substrate 10 corresponding to the bump position indicated by the bump information 104a (step S106), and specifies the bump bonding height from the bump form indicated by the bump information 104a (step S108). .

  Then, the control unit 204 controls the head driving mechanism 202 to move the head 201 that has attracted the component 20 in the direction along the substrate 10 to the site specified in step S106, and the component 20 with respect to the site. The electrodes 23 are made to face each other (step S110).

  Further, the control unit 204 lowers the head 201 from the state described above to press the component 20 toward the substrate 10 and crushes the bump b until the height of the bump b reaches the bump bonding height (step S112). ).

  As mentioned above, although the component mounting method concerning this invention was demonstrated using embodiment, this invention is not limited to this.

  For example, in the present embodiment, the bump position is specified as the coordinate position of the bump b with the origin 0 on the substrate 10 as a reference, but may be specified as a deviation from the original position of the bump b. In this case, based on the individual marks formed on the substrate 10 corresponding to the component 20, the control unit 204 faces the component 20 to the mounting site on the substrate 10 where the component 20 should be originally mounted. As described above, the head 201 adsorbing the component 20 is moved in the direction along the substrate 10. Further, the control unit 204 moves the head 201 in the direction along the substrate 10 by the amount of deviation specified previously.

  In this embodiment, the component mounting system is configured by the bump inspection apparatus 100 and the component mounting apparatus 200. However, the component mounting system may be integrally configured as a component mounting apparatus. That is, the component mounting apparatus also has a function as a component inspection apparatus.

  Further, in the present embodiment, the height and width of the bump b are detected as the bump form, but other elements such as size and weight that specify the form of the other bump b may be detected as the bump form.

  Further, only the height of the bump b may be detected as a bump form. Furthermore, in such a case, without registering the heights of all the bumps b in the bump information 104a, for example, for each bump group corresponding to each component 20, only the height of the lowest bump b is bumped. It is registered in the information 104a. Thereby, for example, even when the component 20 is bonded to the bumps b1 to b4 of the substrate 10, the control unit 204 of the component mounting apparatus 200 has the lowest bump height among the bumps b1 to b4 corresponding to the component 20. The height can be easily grasped from the bump information 104a, and the bump bonding height can be quickly identified from the height of the bump. For each bump group corresponding to each component 20, the lowest bump b height and the highest bump b height may be registered in the bump information 104a.

  Furthermore, in the present embodiment, the bump form of the bump b is detected, but this bump form may not be detected. That is, if the bump b is crushed to the pedestal ba and the sufficient bonding strength is ensured, the control unit 204 of the component mounting apparatus 200 inputs the height of the pedestal ba to the user. Acquired by operation or the like, and the height is specified as the bump bonding height. Also, since there is usually no variation in the height of the pedestal ba of the bump b, even when the component 20 is bonded to a plurality of bumps b, each bump b and the component 20 are securely bonded. Can do.

  In this embodiment, the bump inspection apparatus 100 includes the storage unit 104. However, the storage unit 104 may be configured to be detachable from the bump inspection apparatus 100. Specifically, the storage unit 104 includes a storage medium such as a flexible disk or a memory card. The user inspects the bump with the bump inspection apparatus 100, and takes out the storage medium in which the bump information 104a as the inspection result is written from the bump inspection apparatus 100. Then, when the user inserts the storage medium into the component mounting apparatus 200, the reading unit 203 of the component mounting apparatus 200 reads the bump information 104a from the storage medium.

  In the present embodiment, as described with reference to FIG. 7, the bump bonding height is specified for each bump group corresponding to the component 20, but all the bumps b formed on the substrate 10 are targeted. The bump bonding height may be specified. That is, all the components 20 are pressed against the substrate 10 so that all the bumps b are crushed to the lowest bump bonding height among the bump bonding heights specified for each bump b formed on the substrate 10. As a result, the heights of all the components 20 after mounting become equal. For example, when the components 20 are LEDs (Light Emitting Diodes), it is possible to save the trouble of aligning the heights by polishing or the like.

  Further, in the present embodiment, the bump inspection apparatus 100 detects the bump position and the bump form, but the bump position and the bump form according to the operation by the user may be acquired. That is, the bump inspection apparatus 100 further includes a microscope that allows the user to directly view the object and an operation unit that is input by the user, and the user can view the bump position and bump form from the microscope of the bump inspection apparatus 100. And input the result to the operation unit. The position detection unit 101 of the bump inspection apparatus 100 acquires the bump position input to the operation unit. Similarly, the form detection unit 102 of the bump inspection apparatus 100 acquires the bump form input to the operation unit. To do. Then, the position detecting unit 101 and the form detecting unit 102 output the acquired bump position and bump form to the writing unit 103, respectively.

  The present invention has an effect of improving the bonding quality between a component and a substrate, and can be applied to, for example, a flip chip mounting apparatus.

DESCRIPTION OF SYMBOLS 10 Board | substrate 20 Component 100 Bump inspection apparatus 101 Position detection part 102 Form detection part 103 Writing part 104 Memory | storage part 104a Bump information 200 Component mounting apparatus 201 Head 202 Head drive mechanism 203 Reading part 204 Control part

Claims (1)

Bumps formed on the substrate, so as to come into contact with the electrode formed on the component, a component mounting method for mounting two or more parts before SL on the substrate,
A bump information reading step of reading out bump information indicating a form of a plurality of bumps formed on the substrate from a storage unit;
Based on the bump information read by said bump information reading process, the bumps as the bonding area becomes equal to or larger than a predetermined area at the time when the said electrodes before and Symbol bumps corresponding to the plurality of components to be bonded to the substrate are bonded A bump bonding height specifying step for specifying the lowest bump bonding height among the bump bonding heights specified for each bump formed on the substrate ,
A position detecting step for detecting the positions of a plurality of bumps on the substrate ;
For each position detected by the position detection step, an arrangement step for arranging the substrate and the component so that the electrode of the component faces the position ;
Maintaining the state of being arranged in the arrangement step so that the height of the bumps to be bonded formed on the substrate is the lowest bump bonding height specified in the bump bonding height specifying step. A pressing step of pressing one of the substrate and the component against the other;
A component mounting method comprising: an ultrasonic bonding step for bonding the bump and the electrode by applying ultrasonic vibration.

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