JPS62194632A - Manufacturing equipment - Google Patents

Abstract

PURPOSE:To prevent the successive occurrence of a large number of defects in semiconductor manufacturing equipment, and to facilitate the continuation of each processing process by obtaining the pattern picture of an object to be inspected by a picture processing section on the basis of an image pickup signal from a TV camera and comparing the pattern picture with a standard pattern picture. CONSTITUTION:A picture processing section 8 compares an image pickup signal from a TV camera 7 with the binary-coded threshold of a threshold setting circuit 17 and binary-coding it, and the pattern picture of an object to be inspected is memorized to a pattern memory 19. On the other hand, a standard pattern picture to the object to be inspected is memorized to a pattern memory 20 on the basis of an information from a computer 11. A comparison circuit 10 compares the pattern picture of the object to be inspected and the standard pattern picture from the pattern memories 19 and 20, checks appearance after the attachment of a pellet regarding predetermined items on the basis of a command from the computer 11, and transmits the result over the computer 11.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a pellet that can automatically perform pellet pounding, which is one of the manufacturing processes of semiconductor devices, and that can automatically perform visual calibration. The present invention relates to a manufacturing device equipped with a mounting mechanism.

[Conventional technology]

In the manufacturing process of semiconductor devices, especially in the so-called post-process of mounting the formed element pellets into the required packages, progress is being made in automating each process such as bonding the pellet to the frame, beta processing, wire bonding, etc. There is.

The steps of attaching pellets using a pellet bonder, then baking using a baking device, and then wire bonding using a wire bonder have already been automatically performed using integrated equipment and have been put to practical use.

With the automation of such equipment, a single worker can handle multiple lines of integrated equipment, and TV
The state after pellet attachment in each through-through facility is displayed on a monitor, and while looking at this image, the appearance of each through-through facility after pellet attachment in the pelletizing process is checked (checking for wetting of the pellets). When an operator discovers a defect, the amount of adhesive (Ag paste) applied is controlled.

[Problem that the invention seeks to solve]

However, if an operator has to monitor more than several lines of integrated equipment in this way, it becomes impossible to sufficiently check the appearance after each pellet is attached. For this reason, even if you look at the TV monitor, if you do not notice it, a large number of defects will immediately occur one after another, resulting in a poor yield (and a large number of defects that will impede the consistency of each processing process using the processing equipment). It is the cause.

The purpose of the present invention is to prevent defects from occurring one after another,
It is an object of the present invention to provide a manufacturing apparatus that improves yield and facilitates the integration of each processing step using through-through equipment.

The above and other objects and novel features of the present invention include:
It will become clear from the description of this specification and the accompanying drawings.

[Means for solving problems]

A brief overview of typical inventions disclosed in this application is as follows.

That is, in a manufacturing apparatus equipped with a pellet attaching mechanism having at least a pattern recognition section, the pattern recognition section includes a TV camera arranged to photograph the state after pellet attachment (object to be inspected), and an image from the TV camera. A pattern image of the object to be inspected is obtained from the imaging signal of the object to be inspected, and information regarding the external appearance state of the object to be inspected is obtained from the pattern image of the object to be inspected based on input information from the computer described later. It consists of an image processing unit that compares the image with a standard pattern image and outputs the result, and a computer that performs an appearance check on predetermined items after pellet attachment based on the result and determines the quality. Further, an image of the object to be inspected based on the output signal of the TV camera, that is, an image of the object to be inspected based on the imaging signal (analog signal) K of the TV camera, or a pattern image (binarized A TV that displays images) and displays a predetermined message based on the judgment result of the computer section when the object to be inspected is defective.
It is equipped with a monitor and an alarm device that issues an alarm when the number of inspected objects is a predetermined number, such as when a certain number of defects occur in a row or when the defective state is too severe.

[Effect]

According to the above means, the pattern image of the object to be inspected is obtained by the image processing section based on the image pickup signal from the TV camera, and it is compared with the standard pattern image. After the pellet is attached, the appearance check items are automatically judged to be good or bad, and based on the results, a defective item is displayed on the image of the object to be inspected on the TV monitor, and in certain cases, an alarm system is activated by computer output. Since the system is driven to issue an alarm and notify the occurrence of a defect, the operator does not have to perform an external appearance check (inspection) for specified items after adding the pellets, and furthermore, the operator does not have to perform an external appearance check (inspection) for specified items at all after attaching the pellets. Predetermined measures can be taken automatically. For example, defects in the wetting condition of the pellet can be automatically dealt with by controlling the coating device from the convenience dispenser, adjusting the amount of adhesive applied, and controlling the scrubbing operation. Moreover, defects in the pellet attachment position can be dealt with by controlling the pellet attachment position adjustment mechanism. Therefore, there is no longer a large number of defects that occur one after another as in the past, and the yield can be improved.

〔Example〕

The drawing shows an embodiment of the manufacturing apparatus according to the present invention, particularly a bullet bonder with an appearance inspection function, and particularly shows a pattern recognition section, a coating device, and a scrub control section. Hereinafter, the present invention will be explained using the drawings.

Part of the line has been automated using integrated equipment, from the pelleting process to the plating process to the wire bonding process. Here, the present invention will be described in detail regarding the pelletizing process using a pellet pounder, which has been an obstacle to unification using conventional through-through equipment.

A 5 ml syringe is moved up and down at a constant cycle to the position (called a tab) 3 where the pellet 2 of the lead frame 1 that is placed on the frame feeder and is fed is applied, and Ag paste 4 is applied from the tip of the needle 6, as shown in the figure. Apply as shown. Reference numeral 1a denotes a lead disposed around the tab so as to surround it.

Next, using a bonding arm (not shown), the pellet 2 is placed and pressed onto the tab 3 of the frame 1 coated with the silver paste 4, and is further scrubbed to attach the pellet. The state after pellet attachment (hereinafter also referred to as the object to be inspected) is photographed by a TV camera 7, and the image signal is sent to an image processing unit 8 to obtain a pattern image of the object to be inspected necessary for checking the appearance. sent to.

First, the configurations of the pattern recognition section 9, coating device 23, and scrub control section 24 according to the present invention will be explained.

The pattern recognition unit 9 of the pellet bonder uses a first TV camera 7, a second TV camera 7' that photographs the object to be inspected, seven switches for switching these, and a pattern of the object to be inspected based on the image signals from the TV camera 7 and 7'. At the same time as obtaining an image, the pattern image of the object to be inspected and the standard pattern image previously input into the pattern memory 20 are used to output the appearance state of the object to be inspected by the image processing unit 8 based on input information from the computer 11 described later. A comparison circuit unit 10 for comparison, a computer 11 that sends output signals (control signals and information signals) to the image processing unit 8 and inputs output signals of the comparison circuit unit 10, a marker circuit 12, and a video mixing circuit 13. , a TV monitor 14 that displays an image of the object to be inspected and also displays a predetermined message (for example, ``Poor pellet leakage condition'') when the object to be inspected is defective, and a printer 32 that prints the message.
and an alarm device 15 which issues an alarm based on the output of the computer 11 when the object to be inspected is in a predetermined condition. Here, 16 indicates data exchange, and 16a
indicates data exchange with the CPU of the computer 11.

The image processing unit 8 includes a threshold setting circuit 17 that converts a binarized degree C value based on data from the computer 11 into an analog signal, and a threshold setting circuit 17 that converts the image signal from the TV camera 7 into a threshold setting circuit 17. A binarization circuit 18 that binarizes by comparing it with a digitization threshold, a butter/memory 19 that stores the pattern image obtained by binarizing it by the binarization circuit 18, and a computer 11 via an interface lla. A pattern memory 20 that stores a standard butter 7 image based on the supplied information (standard for the object to be inspected) (turn information), and a pattern fetch circuit 21 that takes in the standard pattern, condition changes, and other initial patterns;
Based on control signals from the computer 11, the TV camera 7, comparison circuit section 10, marker circuit 12. Video mixing circuit 13° pattern memo 1J19,20. It consists of a timing control circuit 22 for synchronizing the pattern fetch circuit 21. Here, the pattern 7 etching circuit 21 may be omitted.

In addition to the pattern recognition section 9 configured as described above, the pellet bonder applies Ag paste to the tab 3 of the lead frame 1.
It is equipped with a coating device 23 and a scrub control section 24 for coating. Here, the coating device 23 includes a timer 25 whose set value is controlled based on a control signal from the computer 11, a solenoid valve 26 controlled by the timer 25, a pressure control valve 31, a pressure detector 33, and a pressure controller 34. Coating amount control section 2
7, and a syringe 5 that discharges the A g paste in synchronization with the supply of the substrate. Further, the scrub control unit 24 receives a scrub operation command (
A motor driver 28 that controls the drive of a motor 29 based on commands such as scrub amplitude, number of scrubs, scrub speed, etc., a motor 29, and a pounding arm 30 that is driven by the motor 29 and performs a scrubbing operation.
Consists of etc.

The operation will be explained below.

As described above, the imaging signal sent to the image processing section 8 is first binarized by the binarization circuit 18, and the pattern image of the object to be inspected is stored in the pattern memory 19. On the other hand, a standard pattern image for the object to be inspected is stored in the pattern memory 20 based on information from the computer 11. The comparison circuit section 20 uses these pattern memories 19
The pattern image of the object to be inspected from 20 and 20 is compared with the standard pattern image, and the appearance check after pellet attachment is performed based on the instructions from the computer 11, for example, as shown in (1) below.
- (8) and send the results to computer 1.
Send to 1.

(1) Wetting condition of the two pellets (check the amount of Ag paste 4 protruding from the bottom of the pellet 2) (2) Position of the pellet (check the amount of deviation from the reference value) (3) Lead frame 1 Scratches and chips on pellet 2 (4)
2. Ag paste adhesion to the IJ-dead 1a side (5) Foreign matter adhesion to the pellet 2 and lead 1a (6)
Deformation of lead frame 1 (7) Condition of plating (especially Ag plating) on lead la side (8) Lead hole, presence or absence of pellets, other pellets,
Frame abnormal computer 11 has a defect in check item (1) or (4), and for example, the same check item (
If a defect occurs in 1) or (4), the set value of the timer 25 of the dispensing amount control section 27 is automatically changed (switched), and the solenoid valve 26 is opened or closed according to this set value. For example, the setting value (setting time) of the timer 25
When the solenoid valve 26 is opened), air (or other gas) at a constant pressure supplied via the pressure control valve 31 is added to the syringe 5, and from the tip of the needle 6, the lead frame 1 to be sent next is heated. The Ag paste 4 is applied to the tab 3 in an amount corresponding to the setting value of the timer 25 by vertically moving the syringe 5 at a constant period. The air pressure is arbitrarily set by the pressure control valve 31 via the pressure controller 34 according to instructions from the computer 11.

Then, after transporting it to the next position on the frame feeder,
The pellet 2 is placed so as to be pressed against the tab 2 by the bonding arm, and then the motor 2 of the scrub control section 24 is activated based on the scrub operation command from the computer 11.
9, the pellet 2 is bonded to a predetermined position (tab 3) of the lead frame 1 while performing a scrubbing operation as instructed by the bonding arm.

After bonding the pellet 2 in this manner, the state of the wetting 4' of the pellet 2 becomes a constant wetting state, and the Ag paste does not adhere to the pad side or the lead side. Note that the quality of the wetted state of the pellet 2 is determined based on, for example, the wetted area. In addition, in the scrubbing operation, the number of times of scrubbing, the scrubbing amplitude, and the scrubbing speed are varied depending on the degree of wetting (wetting area).

Furthermore, an image of the object to be inspected is displayed on the TV monitor 14, which is supplied as an analog signal from the TV camera 7 via the video mixing circuit 13, and based on instructions from the computer 11, the marker circuit 12. Messages (failure items among check items (1) to (8) and the fact that they are defective) supplied via the video mixing circuit 13 are displayed. This allows the operator to know the condition after pellet attachment in the pellet attachment process by looking at the screen of the TV monitor 14, and if there is a defect in the check item, the defect item and a message indicating the defect are displayed on the screen. However, since the same content is outputted to the printer 32, the extent of the defective portion can be immediately grasped from the image of the object to be inspected. Even if the operator does not watch the TV monitor 14, it is possible to ensure that there is no problem as long as the alarm device 15 does not issue an alarm.In other words, for example, if the same check item is defective, 1
If this is the case, it is sufficient to proceed directly to the subsequent wire bonding process and remove it during the visual inspection performed with a wire bonder. In a wire bonder, the defective frames mentioned above and the defective frames after wire bonding are automatically sent to a stocker or the like for storing defective frames in order to distinguish them from non-defective frames, and only the non-defective frames are sent to the next process. Further, if the same check item fails several times in a row, for example twice, the computer 11 drives the alarm bag [15 through the interface 11a to issue an alarm to notify the operator, as there is a risk that the same check item will fail several times in a row. The operator immediately hears the alarm and can see the pellet in question, its defective location, and the extent of the defect on the TV monitor 14. If check items (1) and (4) are defective among check items (1) to (8), change the coating amount by coating device 23 or scrub control unit 24.
It is sufficient to automatically change the scrubbing conditions according to the above, and if the check item (2) is found to be defective, the bonding arm may be controlled by the computer 11 to automatically change the position where the pellet is attached. However, in the case of defects in check items (3) and (51 to (8)), the pellets are automatically sent as defective pellets or defective frames to a stocker for storing defective products, to distinguish between good and defective products. Proceed to the next process. Only quality products are passed on.

After completing the pelleting process as described above, baking is then performed in the baking process. Next, in a wire bonding step, the pads and leads are wire bonded using a wire bonder. A plurality of integrated facilities, for example, several lines or more, are installed to consistently perform each of these processes, and are placed under the supervision of -100 workers. However, in the present invention, each bullet bonder of each through-hole facility has a pattern recognition section 9 as shown in the figure. Coating device 23. It has a scrub control section 24, and even if an operator is not accompanying the pellet bonder, pattern recognition is automatically performed by the pellet bonder itself, that is, by the pattern recognition section 9, and the appearance is checked according to predetermined items (1).
~ (8) etc., and if the defect is discovered,
TV monitor 1. Hc irregular items are displayed. If the TV monitors 14 of each through-hole equipment are installed in parallel at one place so that workers can see them at a glance, each machine will only be alerted when an alarm is issued by the alarm device 15, even if the operator is not attached to the pellet bonder. Looking at the screen of the TV monitor 14, from the image of the object to be inspected and the defective items, it is possible to determine which equipment is in the verging/grooving process.
It is possible to know whether either the lead frame or the pellet is defective, or whether both are defective, and the extent of the defect, and necessary measures can be taken immediately.

Since the appearance check is automatically and reliably performed by such a pellet bonder, that is, by the pattern recognition section 9 of the pellet bonder, there is no possibility of the appearance check being carelessly neglected or overlooked as in the conventional case. Therefore, since multiple defects do not occur one after another, the yield is further improved, the quality is stabilized, and it becomes easier to integrate through-through equipment.

Note that the TV monitor 14 receives the TV camera 7 as an image signal.
A binarized pattern image signal may be used instead of the imaging signal from the image sensor, and in this case, a binarized pattern image is obtained.

The effects obtained from the above-described embodiments of the present invention are listed below.

(1) The pellet bonder is equipped with a pattern recognition unit that automatically checks the appearance of the pellet after it has been attached. Since this notification is provided, it is possible to prevent defects from occurring repeatedly at a high rate of tK, thereby improving yield and stabilizing quality.

(From 21(1)K onwards, a beretting process using integrated equipment.

It is possible to easily integrate the baking process and the wire bonding process.

(3) Even when one worker has to monitor several lines or more of integrated equipment as in the past, the worker does not have to be present at each bullet bonder, making the monitoring extremely easy.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the above Examples and can be modified in various ways without departing from the gist thereof. Nor. For example, although CAg paste is used as the adhesive, Au-8i eutectic may also be used. Pellet attachment is carried out by rubbing pellets together on a heated heat column, but if the wetting condition of the pellet is poor compared to the standard condition, the computer 11 will pre-register according to the wetting condition. Based on the input data, the motor driver circuit 28 drives and controls the motor 29 to vary the number of scrubs, scrub amplitude, and scrub speed.

In addition, the alarm device 15 is activated to issue an alarm based on the output of the computer 11, but in some cases, for example, if one defective product occurs and you want to know immediately,
Immediately by the output of the abnormality determination unit 10 (defective determination signal)
The alarm may be issued by driving the # alarm device 15.

In the above explanation, the invention made by the present inventor was mainly applied to pellet attachment using Ag paste, which is the background field of application, but the invention is not limited thereto. Can be applied to attaching pellets with crystals, etc. Incidentally, as the pellet, a pellet for all ICs can be used.

〔Effect of the invention〕

(1) The bullet bonder is equipped with a pattern recognition unit that automatically checks the appearance after attaching the bullet. Since it notifies you, it is possible to prevent defects from occurring one after another with multiple values, thereby improving yield and stabilizing quality.

(2i (11) Pelleting process using integrated equipment.

It is possible to easily integrate the baking process and the wire bonding process.

(3) Even when one worker has to monitor several lines or more of integrated equipment as in the past, the worker does not have to be present at each bullet bonder, making the monitoring extremely easy.

[Brief explanation of drawings]

The drawing is a main part configuration diagram showing an embodiment of a pellet bonder of a manufacturing apparatus according to the present invention. 1...Lead frame, 1a...Lead, 2...
Beret, 3...Tab, 4...Ag paste, 7.
...TV camera, 8...Image processing unit, 9...Pattern recognition unit, 10...Abnormality determination unit, 11...Computer, 14...TV monitor, 15...Alarm device,
23... Coating device, 24... Scripe control section, 27... Coating amount control section.

Claims (1)

[Scope of Claims] 1. A semiconductor product or its component after or during pellet attachment in a semiconductor manufacturing device equipped with a pellet attachment mechanism for assembling pellets of semiconductor or the like onto a substrate by adhesion or alloy formation. A manufacturing device that has a mechanism for inspecting the external appearance of an object to be inspected. 2. The appearance state inspection mechanism includes a pattern recognition section, and the pattern recognition section includes at least an imaging mechanism for photographing the appearance of the object to be inspected, and processes signals from the imaging mechanism to obtain a pattern image. 2. The manufacturing apparatus according to claim 1, further comprising: a signal processing section for detecting the pattern; and a recognition section for recognizing the state of the object to be inspected using the pattern image. 3. The appearance state inspection mechanism includes a pattern recognition section, and the pattern recognition section includes at least an imaging mechanism for photographing the appearance of the object to be inspected, and processes signals from the imaging mechanism to obtain a pattern image. The system is composed of a signal processing unit for detecting a signal, and a recognition unit that recognizes the state of the object to be inspected using this pattern image, and compares the pattern image from the pattern recognition unit with a standard pattern image that has been input in advance. 2. The manufacturing apparatus according to claim 1, further comprising a pattern recognition mechanism that performs pattern recognition by performing pattern recognition. 4. Items to be inspected include the state of application of the adhesive for attaching the pellets on the substrate, the position of the pellets after attaching the pellets, the shape of the pellets after attaching the pellets, and the adhesive or alloy that protrudes from the pellets and spreads onto the substrate after attaching the pellets. It is characterized by at least one of the pattern shape of the layer, the presence or absence of deposits on the pellet surface, the shape of the circuit pattern formed on the pellet, and identification marks such as product name and type provided on the pellet or substrate. A manufacturing apparatus according to claim 1. 5. At least in semiconductor manufacturing equipment equipped with a pellet attaching mechanism for assembling semiconductor pellets onto a substrate by adhesion or alloy formation, the appearance state of the semiconductor product or its component to be inspected after or during pellet attachment. 1. A manufacturing apparatus comprising: an inspection mechanism, and a condition control mechanism that sets or controls operating conditions of a pellet attachment mechanism based on an output from the inspection mechanism. 6. At least in semiconductor manufacturing equipment equipped with a pellet attaching mechanism for assembling semiconductor pellets onto a substrate by adhesion or alloy formation, the appearance state of the semiconductor product or its component to be inspected after or during pellet attachment. What is claimed is: 1. A manufacturing apparatus comprising: an inspection mechanism, a determination result output mechanism that compares and determines the output from the inspection mechanism with predetermined inspection reference data, and outputs the determination result to the outside. 7. A device that is equipped with at least a pellet mounting mechanism for assembling pellets of semiconductors, etc., onto a substrate, and that has at least the function of inspecting the state of a semiconductor device, etc. after pellet mounting or during pellet mounting, and A pattern image of the object to be inspected is obtained by signal processing the imaging signal from the imaging mechanism arranged to capture the condition, and the pattern image is used to determine the appearance condition of the object to be inspected by pattern recognition. Semiconductor manufacturing equipment includes an image processing section for obtaining output, and a computer for calculating state quantities of an object to be inspected and determining quality based on the output of the image processing section. 8. The object to be inspected is equipped with a TV monitor that displays a predetermined message based on the determination result of the abnormality determining section, and an alarm device that issues an alarm when the object to be inspected is in a predetermined manner. A manufacturing apparatus according to claim 7. 9. The manufacturing apparatus according to claim 8, wherein the alarm device issues an alarm based on an output from a computer. 10. The manufacturing apparatus according to claim 8, further comprising a condition control section that controls pelletizing operation conditions based on information obtained from the pattern recognition section. 11. The manufacturing apparatus according to claim 8, which is provided with a function of automatically discriminating the object to be inspected that has been completely loaded with pellets based on the inspection result and storing it or sending it to the next process.