JPS6281039A - Method for positioning microscopic pitch - Google Patents

Abstract

PURPOSE:To perform position measuring and positioning operations without having restriction on the gap between jointed parts and the quality of material in a highly accurate manner by a method wherein a common dummy pattern is provided on the junction surface of two jointed parts which are the object of positioning, a standard pattern plate is mounted on an optical measuring means, and the positional correction of the wiring pattern and the dummy pattern of the two jointed parts are performed in line with the standard pattern plate within the field of an optical measuring means. CONSTITUTION:The position of a circuit module substrate 23 is measured in the field of observation of a charge coupled device (CCD) 6, and the comparative processing is performed on a standard pattern 21 and a dummy pattern 22, and a wiring pattern 26 and a dummy pattern 27 using a data processing device 9. A positional measurement is performed on an EPC 30, with which the position of the circuit module substrate 23 is corrected, in the field of observation of the CCD 6 using a table driving device 2, and the comparative processing is performed on the standard pattern 21 and the dummy pattern 22, and a wiring pattern 31 and a dummy pattern 32 is preformed by using the data processing device 9. The position of the FPC 30 is corrected by a hand-driving device 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a fine pitch positioning method, particularly in precision machining processes or precision assembly equipment.

The present invention relates to a fine pitch positioning method suitable for positioning circuit modules, wiring films (FPC), etc. based on visual information, for example.

[Background of the invention]

In recent years, thin film modules and flat package LSIs have
With high integration, the number of connection wires is 200 in a small area.
There are some that exceed the size of a bottle, and the pitch has become as fine as 100 μm or less. Further, the wiring pitch of a high-resolution thermal recording head (eg, 16 dots)/w is a little over 60 μm, and these connection techniques or inspection techniques require highly accurate positioning. For example, as a connection technology for such fine wiring, laser marking/dapping is promising, but its positioning device, including an optical measurement unit, is complicated and expensive.

Conventionally, many optical measurement units use a TV camera, but the TV camera has a problem of low resolution and the inability to obtain a large observation field of view. Recently, charge-coupled devices, which are high-resolution visual sensors, have been developed.
Measurement methods using CCDs (hereinafter referred to as CCDs) are popular, but the devices are still complex and expensive, and there are many restrictions on use. Another problem was that the software burden was heavy.

Technologies aimed at precision position measurement or precision positioning can be found in semiconductor manufacturing technologies such as mask aligners. For example, the "pattern relative position detection method" described in JP-A-52-11774 uses mask alignment technology, and the gap between the mask and the wafer is 10 to 50 μm.
In addition, the mask is transparent and the target mark formed on the mask is aligned with the target mark on the wafer for positioning, and there are many constraints, and it is difficult to use for assembly or wiring connection. This is different from the fine pitch positioning according to the present invention.

[Purpose of the invention]

The present invention has been made in view of the actual state of the prior art described above, and it is possible to perform position measurement and positioning for making fine-pitch wiring connections as part of precision machining or precision assembly. Without being restricted by materials,
The purpose is to provide a fine pitch positioning method that can be performed with high precision.

[Summary of the invention]

The fine-pitch positioning method according to the present invention is a fine-pitch positioning method in which two bonded parts to be wire-connected in a tiny pinch are positioned while being observed with an optical measuring means, and there is no support means for the object to be positioned. , using a positioning device equipped with an optical measurement means that includes at least a visual sensor and a zoom mechanism, and a control system that processes optical information in the observation field of the optical measurement means and operates the support means for the positioning object. , a common dummy pattern is provided on the bonding surfaces of two bonded components of the object to be positioned, and the optical measurement means of the positioning device is equipped with a standard pattern board serving as a reference for the micro-pitch wiring pattern of the bonded components and the dummy pattern. , a method of activating the control means of the positioning device so as to correct the positions of the wiring patterns and dummy patterns of the two bonded parts according to the standard pattern board using a zoom mechanism within the observation field of the optical measurement means; be.

It should be noted that a feature of the present invention is that two joint parts that are positioning objects have common coordinates. That is, for example, the visual recognition area of the joint part in wiring connection, in other words, the observation field of view, is patterned, the standard pattern board is installed in the optical measurement unit, and the zoom mechanism is controlled to focus the measurement of two parts. By automatically performing the alignment, the alignment of wiring connection portions at minute pitches can be managed using one coordinate and a reference point.

Precise positioning requires more precise measurement, but by using a high-resolution COD as a visual sensor and combining it with a cylindrical lens, it is possible to collect optical information (reflected light) within the observation field. By performing dimensional processing, it is possible to simplify the device and data processing.

Note that the illumination is a vertical epi-illumination method.

The measurement and positioning procedure is as follows: First, the object to be positioned is observed with the COD through a 7-lindrical lens, and the output is compared with the observation data of the standard pattern to determine the positioning object in the X, Y, and angle θ directions. The amount of positional deviation is calculated and further converted into a positional correction amount that matches the resolution of the positioning device to control the positioning device.

In addition, since the material of the positioning target has a large effect on visual measurements such as optical reflectance, highly reliable data determined experimentally, such as judgment reference lines (threshold values) associated with reflectance, should be compiled in advance into a table. By performing software processing, measurements can be made without restrictions on materials or gaps between two parts.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 11.

First, in order to facilitate the following explanation, main parts of the embodiment will be explained along with a brief explanation of the drawings.

FIG. 1 is a configuration diagram of a positioning device to which a positioning method according to an embodiment of the present invention is applied, in which a wiring connection film (1; "1exible print C
The present invention is directed to a positioning device for soldering FPC (hereinafter referred to as FPC) using a laser.

FIG. 2 is a front view of the circuit module that is the object to be positioned, and FIG. 3 is a side view of the circuit module in FIG.
5 and the thick film circuit module 28.29,
This is a soldered FPC30.

FIG. 4 is a partially enlarged front view of the thin film circuit module 25 and the wiring pattern 26 for connection, which is a part of the circuit module. , a dummy pattern for positioning.

FIG. 5 is a simulated enlarged view of the FPC 30 which is a positioning object, and the circular patterns 32 at both ends of the wiring pattern 31 are positioning marks similar to the dummy butter/in FIG. 4.

FIG. 6 is an enlarged front view of the standard pattern plate installed in the optical measurement unit.

The standard pattern board 20 is common and serves as a reference for the wiring pattern 26 of the thin film circuit module 25 shown in FIG. 4, which is the positioning object, and the wiring pattern 31 of the FPC 30 shown in FIG. 5, and varies depending on the object. It is something. This depends not only on the shape of the object, but also on other factors, such as:
When the optical reflectance of the bank ground of the standard pattern plate 20 and the materials of the standard pattern 21 and the standard circular patterns 22 are reversed, the observed data naturally changes, which is shown in FIG.

Figure 7 (,) is an observation example when a material with high reflectivity is used for the standard pattern plate 20, and is the output waveform of the CCD 6 through the cylindrical lens 9 shown in Figure 1. This is done so that the pattern 21 and the standard circular pattern 22 can be clearly recognized. Also, Figure 7 (
For b), the material and configuration of the actual object to be measured may be different, and the background may be darker than the wiring pattern, that is, the reflectance may be lower. To cope with this, the waveform is equipped with a data inversion function. Give an example.

FIG. 8 is an explanatory diagram showing the positional state of the FPC 30 observed within the observation field 35 of the optical measurement unit.
Wiring pattern 31. The circular pattern 32 is the standard pattern 21. It shows a state that is deviated from the standard round butter/22.

Figure 9 shows the observed waveform of the observation target shown in Figure 8.
Figure (a) is a waveform showing the positional deviation situation, Figure 9 (b)
shows the normal waveform after position correction.

To summarize the above, FIG. 10 is a diagram explaining the principles of measurement and position correction regarding the positioning method of this embodiment, and FIG. 11 is a flowchart showing the operating procedure of the positioning method.

Next, details of this embodiment will be explained first, starting with the configuration of the positioning device shown in FIG.

In FIG. 1, 1 is an XYθ table for positioning the circuit module board 23, 2 is a table drive device that operates the XYθ table 1 in the X and Y directions and the inclination angle θ, and 3 is an FPC 30. This is a hand for positioning and mounting, and the FPC 30 is vacuum-suctioned to the hand 3 by a vacuum device 5. Reference numeral 4 denotes a hand driving device for operating the hand 3, and the XYθ table 1 and the hand 3 constitute means for supporting the object to be positioned.

6 is a charge-coupled device (hereinafter referred to as COD) related to a visual sensor, 7 is a cylindrical lens that compresses and averages the optical information per area in the observation field, which is so-called -dimensional processing; Together with the zoom mechanism shown, this is a main component of an optical measurement unit related to optical measurement means.

8 is an image processing device that performs multi-value processing on the output waveform of the CCD 6; 9 is an image processing device that performs multi-value processing on the output waveform of the CCD 6; and 9, observation data of the positioning target from the image processing device 8, data extracted from the data table, and data obtained from the standard pattern. This is a data processing device that outputs the position correction amount of the positioning target to the table driving device 2 and the hand driving device 4 according to the significant difference, and the image processing device 8, the data processing device 9. The table drive device 2 and the hand drive device 4 constitute a control system that operates the means for supporting the object to be positioned.

As already mentioned, the optical measurement unit uses a high-resolution CCD 6 as a visual sensor and has a structure that allows it to observe the circuit module substrate 23 on the XYθ table 1 and the FPC 30 vacuum-adsorbed on the hand 3. However, to explain in more detail, a cylindrical lens 7 and an interference filter 10 are arranged in front of the CCD 6, and the objective lens 15 is connected to the circuit module substrate 23 by controlling a zoom mechanism 16 with a motor 17. FPC30 for wiring
Focusing is automatically performed. Therefore, there is no restriction on the gap between two positioning objects.

The illumination is configured such that a light source of a mirror 11 is focused on a lens 12 and vertically illuminated illumination light is obtained via a half mirror 13.

In addition, a standard pattern board 20 is installed in the same measurement unit as a reference point for measurement and positioning, and a half mirror
14. Observe with CCD 6 through objective lens 19,
In order to facilitate image processing and data processing, a shutter 18 is provided to switch images so as to avoid overlapping with images of the object to be measured.

The object of positioning in this embodiment is as shown in FIGS. 2 to 5.
This is the wiring assembly of the circuit module shown in the figure.

This is because the thin film circuit module 25 and the thick film circuit module 28 and 29, which are produced in different manufacturing processes, are configured on both sides of the ceramic circuit module substrate 23, so the final connection using the FPC 30 for wiring is required. It is something that becomes.

In recent years, with the increasing integration of circuit modules, the number of wires has increased in a small area, so the wiring pitch has become extremely small, less than 100 μm.
Naturally, precise position measurement and precise positioning are required.

Therefore, as an example of a fine pitch positioning method, the fourth
The measurement and positioning method for assembling and wiring the wiring pattern 26 connected to the thin film circuit module 25 shown in the figure and the wiring pattern 31 of the FPC 30 shown in FIG. 5 will be described below with reference to FIGS. 6 to 11. explain.

FIG. 6 is an enlarged view of the standard pattern board 20, which serves as a reference for measurement and positioning of the object to be measured, that is, the positioning target, so that the wiring pitch, line width, etc.
It is also optically adjusted so that the data observed at 6 is the same as that of the object to be measured. Among these, Danbrush pattern 2
1 is actually quite large in number, so when the same pattern is continuous, circular patterns 22 are formed as dummy patterns at both ends to determine the position of the end and to serve as a counting reference. Therefore, the circuit module board 23, which is the object to be measured, that is, the object to be positioned, and the F
Similarly, circular patterns 27 and 32 are formed on the PC 30 as dummy butter 7, respectively.

When the standard pattern plate 20 is observed with the CCD 6 through the cylindrical lens 9, assuming that the back ground is optically bright and the reflectance of the quasi-pattern 21 and the circular pattern 22 is low, the output waveform is as follows. Figure 7 (
It will be like a). From this waveform 33, with the wave height value Va as the background, the concave part of ■b is the circular pattern 2.
2. The concave portion of Vc indicates the aIL pattern 21.

Also, due to changes in the material of the object to be measured, 1. (The optical reflectance of the ground and observation pattern is shown in Figure 7 (a)
) The seventh waveform was processed by equipping the image processing device 8 with an inversion function, assuming that there may be cases where the waveform 33 is reversed.
This is the waveform 34 in Figure (b). In this case, the peak values Va, V
The relationship between b and Vc is reversed from that of waveform 33.

Therefore, the observation field 35 (the 8th
For observation of the object to be measured (see figure), it is sufficient to input data determined experimentally in advance, such as the reflectance of the material.
By setting and controlling a threshold value in the vicinity, the standard pattern plate 20 can be effectively applied as a standard over a wide range of areas.

FIG. 8 is an example of observation of the FPC 30, in which a wiring butter y 31 ) circular pattern 32 captured within the observation field 35 is compared with the standard pattern 21 and the circular pattern 22 of the standard pattern board 20.

For the sake of explanation, first, we will start with the CCD 6 in the normal positioning state.
Looking at the output waveform, it becomes waveform 37 in FIG. 9(b). This is compared to the standard waveform 33 of the standard pattern 21, including the wave height value Va' of the background, the wave height value Vb/' of the concave portion indicating the circular pattern 32, and the wave height of the concave portion indicating the wiring pattern 31. (rfLvC' indicates that the material has an overall low reflectance. Here, it can be confirmed that there is no horizontal direction or tilt (rotation angle deviation), but the vertical position deviation High value Va', Vb
'.

Since it appears in vC', normal value data must be confirmed in advance.

・ Returning to FIG. 8 again, the comparison between the observation data of FPC 30 and the standard pattern 21 is as shown in FIG. This clearly shows the inclination with respect to the detection axis.

The waveform observed by the combination of the CCD 6 and the cylindrical lens 9 appears as an integral value obtained by one-dimensionally processing the optical information of an area of 3 in the observation field of view 35, so the inclination of the wiring pattern 31, which is the object to be positioned, is , appears at Vc"-vcl in FIG. 9(a).

This inclination will be explained with reference to FIG.

In FIG. 10(a), if the tilt angle of the FPC 30 captured within the observation field of view 35 is θ, the output of the CCD 6 becomes a waveform 38 in FIG. 10(b), and the dashed line detected from this waveform 38 is The slope 39 shown can be converted to FIG. 10(C).

As shown in FIG. 9(a) and FIG. 10(C), the length of the wiring pattern is t, and the slope is Vc''-VC' as described above.
The angle of the inclination is θ! If so.

Vc" - Vc' = l*tanθ1...
・(1) 0=-k (Vc"-Vc')/l
−=・(2).

Here, the coefficient - is h shown in FIG. 10(a) and (V
c''-Vc'), but since it is affected by the optical reflectance of the positioning target and the illumination conditions, experimentally reliable data must be created into a table and processed within the data processing device 9. .

In summary, the positioning method of this embodiment starts with measuring the object to be positioned, and first corrects the inclination angle based on the measured data.

To correct the tilt angle, convert the data obtained from equation (2) above into a correction amount that matches the resolution of the positioning device, and
This is done by controlling table 1 and hand 3.

Next, the X direction and Y direction are corrected, but the X direction is CC
The difference between the standard pattern 21 and the D6 bit correspondence is corrected. Further, since the correction in the Y direction is affected by the reflectance of the positioning object in the same way as the correction of the tilt angle, the correction is performed by setting a threshold value using a data table. In both cases, the XYθ table l related to the means for supporting the positioning target
and hand 3 to control and correct them.

The control system, as shown in FIG.
The observation data of the positioning target is compared with the data extracted from the data table and the data obtained from the standard pattern 21, and the position correction amount of the positioning target calculated according to the significant difference is calculated by the table driving device 2. The position is corrected by outputting the data to the hand drive device 4 and driving the XYθ table 1 and hand 3.

FIG. 11 shows an operation flowchart of the positioning method according to this embodiment.

First, a data table is input into the data processing device 9 and stored (procedure ①). On the other hand, the standard putter/board 20 is measured, and the data of the standard pattern 211, circular pattern 22, etc. is also taken into the data processing device 9 and stored (procedure ■).
. Note that the data of the data table is stored in the ROM area, and the data of the standard pattern board 20 is stored in the RAM area.

Next, the circuit module board 23, which is one of the objects to be measured, that is, the object to be positioned, is mounted on the XYθ table 1, and
The position is measured in the observation field 35 of the CCD 6, and the data processing device 9 compares the standard pattern 21 and circular pattern 22 of the standard pattern board 20 with the wiring pattern 262 and circular pattern 27 of the thin film circuit module 25. 2 is activated to correct the position of the circuit module board 23 (Steps ① to ③).

Next, the FPC 30, which is an object to be measured, that is, one of the objects to be positioned, is vacuum-adsorbed to the hand 3, and its position is measured in the observation field 35 of the CCD 6, and the standard pattern 212 circular pattern 22 of the standard pattern board 20 and the wiring pattern of the FPC 30 are 31. A comparison process with the circular pattern 32 is performed by the data processing device 9, and the hand drive device 4 is operated to
30 position corrections (Steps ■ to Steps @).

As a result, the wiring butter 726 of the thin film circuit module 25 on the circuit module board 23. The positioning of the circular pattern 27 and the wiring pattern 31° of the FPC 30 and the circular pattern 32, that is, the positioning of the minute pitches for wiring connections, is performed using the standard pattern 21. of the standard pattern board 20. Using the circular pattern 22 as a common reference, in other words, the processing is performed at the same coordinates.

Then, activate hand 3, lower FPC 30,
Perform the specified wiring connections (procedure @). The workpieces that have been joined are transported to a predetermined location and the work is completed (steps @ ~ [
phase]).

In this way, by equipping the optical measurement unit with the standard putter/plate 20 and the zoom mechanism 16, it is possible to improve the joining work that requires wiring connections at minute pitches by:
is not constrained by the gap between two positioning objects.

2) Not restricted by the material of the positioning target, 3) XYθ
The problems of the prior art are solved, such as there being no need to set a reference point for positioning on the support means of the positioning device, such as the table 1 or the hand 3.

In addition, in terms of measurement software, the positioning method of this embodiment performs all processing using one coordinate based on a standard pattern, thereby simplifying data processing.

In addition, according to the above-mentioned embodiment, the circuit module board and the F
Although an example of wiring connection with a PC has been described, the present invention is not limited to this, but can be widely applied to positioning, precision processing, or precision assembly of parts that need to be connected with wiring at minute pitches, where similar effects are expected. It is something that will be done.

For example, the range of applications is wide, such as positioning when wiring circuit modules and soldering flat package LSI wiring using a laser processing machine, and positioning for precision assembly of electronic components and small parts, and the precision will continue to increase in the future. This is an essential basic technology for automation technology that requires

This can be expected to improve the quality and yield of precision processing or precision assembly equipment.

〔Effect of the invention〕

As described above, according to the present invention, position measurement and positioning for making fine pitch wiring connections as part of precision machining or precision assembly are not limited by the gaps between the parts and the materials of the joined parts. It is possible to provide a fine pitch positioning method that can be performed with high precision without any problems.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a positioning device to which a positioning method according to an embodiment of the present invention is applied, FIG. 2 is a front view of a circuit module that is an object to be positioned, and FIG.
FIG. 4 is a partially enlarged front view of the thin film circuit part of the circuit module, and FIG. 5 is an enlarged view of the FPC that is the object to be positioned.
Figure 6 is an enlarged front view of the standard pattern board, Figure 7 is a diagram of the output waveform of the CCD via a cylindrical lens, Figure 8 is an explanatory diagram showing the positional state of the FPC observed in the observation field, 9 is an observed waveform diagram of the observation target shown in FIG. 8, FIG. 10 is an explanatory diagram of the principle of measurement and position correction regarding the positioning method of this embodiment, and FIG. 11 is a flowchart showing the operating procedure of the positioning method. It is. 1...XYθ table, 2...Table drive device,
3...Hand, 4...Hand drive device, 6...C
CD, 7... Cylindrical lens, 8... Image processing device, 9... Data processing device, 15.19...
Objective lens, 16... Zoom mechanism, 20... Standard pattern board, 21... Standard pattern, 22... Circular pattern, 23... Circuit module board, 25...
Thin film circuit module, 30...FPC, 26, 31.
...Wiring pattern, 27°32...Circular pattern, 3
3, 34, 36, 37° (1 sword) lru J, #l eyes 20 eyes 3 eyes 4th. Kuchi 59 Imo 6 Komo 7me Kayo I Ko , 5

Claims (1)

[Claims] 1. A micro-pitch positioning method for positioning two bonded components to be wire-connected at a micro-pitch while observing them using optical measurement means, the method comprising: supporting means for the object to be positioned; and at least a visual sensor. A positioning device is used that includes an optical measurement means having a zoom mechanism, and a control system that processes optical information in the observation field of the optical measurement means to operate the support means for the positioning object. A common dummy pattern is provided on the bonding surfaces of the two bonded components, and the optical measurement means of the positioning device is equipped with a standard pattern plate serving as a reference for the micro-pitch wiring pattern of the bonded components and the dummy pattern, and the optical measurement The control means of the positioning device is operated to correct the positions of the wiring patterns and dummy patterns of the two bonded parts according to the standard pattern board using a zoom mechanism within the observation field of the means. Positioning method. 2. In the method described in claim 1, a charge-coupled device is used as the visual sensor of the optical measurement means, and the object to be positioned is observed by combining the charge-coupled device and a cylindrical lens. The optical information per area in the observation field is processed one-dimensionally, the data is compared with the observation data of the standard pattern board, and the position of the positioning target is corrected by operating the control means according to the significant difference. Fine pitch positioning method.