JPH02187095A - Device for forming thick film circuit - Google Patents

Abstract

PURPOSE:To improve accuracy of film thickness and to form a thick film circuit with good yield by providing a paste discharge nozzle and a measuring device of film thickness. CONSTITUTION:A height of a substrate and a thickness of a paste film are measured by using a distance measuring devices 3, 5 by the use of a laser. A measured value L2 of a thick film paste 4 immediately after pattern generation is obtained against a measured value L1 of a height of a substrate 2. L1-L2 is operated and a picture is drawn comparing it with a set film thickness. A film thickness value L1-L2 is taken into an operation section 13, and fed back to operation of each actuator to realize the set film thickness value through control devices 15, 14, 17 of a height, a discharge amount, and an XY tables, respectively. The operation section 13 is provided with informations relevant to each control and controls film thickness with high precision changing drawing conditions. As a result, defective reduces greatly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for forming a thick film circuit constituting an electronic circuit or the like.

2. Description of the Related Art A conventional method for forming a thick film circuit using a drawing device will be explained below with reference to FIG. In the same figure, 1 is a nozzle,
A thick paste is discharged onto a substrate. Nozzle 1
The nozzle 1 moves on the substrate 2 while discharging the thick film paste 4 while keeping the distance between the substrate 2 and the substrate 2 constant using a substrate height measuring device 3, thereby drawing.

As the thick film paste, a resistor paste, a conductor paste, a dielectric paste, etc. are used, and after the paste is drawn, a thick film circuit is formed through a drying process and a baking process.

Problems to be Solved by the Invention However, with the above apparatus, as shown in the process diagram of FIG. 9, it is necessary to go through a drawing process, a drying process, a sample extraction process, and a film thickness measurement process before finding a film thickness defect. , which had the problem of long loss time.

Furthermore, the accuracy of the device cannot be guaranteed due to the lack of rigidity due to the head movement and the ribbed structure for detecting the nozzle height. The positional relationship of the height measuring device 3 and the film thickness measuring device 5, the installation of the above-mentioned both side measuring devices has many problems such as the position and code processing.

Therefore, in order to solve this problem, the present invention provides a thick film circuit forming apparatus that significantly reduces loss time in the event of failure.

Further, the present invention provides a thick film circuit forming apparatus that increases the accuracy of film thickness and significantly reduces the number of defects.

Means for Solving the Problems A device according to a first invention for achieving the above object includes a nozzle for discharging a thick film paste onto a substrate, and a film thickness control device for discharging a thick film paste onto a substrate by the nozzle. The measurement device includes a measurement device that measures the height of the substrate, and a measurement device that measures the height of the thick film circuit formed on the substrate. The film thickness is calculated by taking the difference.

In addition, a second invention for achieving the above-mentioned second object includes a memory section for storing the film thickness measured by the above-mentioned apparatus, a calculation section for comparing the film thickness with a set film thickness, The apparatus further includes a control means for changing the drawing conditions according to an instruction from the arithmetic unit.

Furthermore, a third aspect of the apparatus for achieving the second object is provided with a discharge amount control device for increasing or decreasing the amount of thick film paste discharged from the nozzle as the control means.

Further, in the device of the fourth invention for achieving the second object, the control means increases or decreases the height of the head to which the nozzle is fixed in order to increase or decrease the distance between the nozzle and the substrate. A head height control device is provided.

Furthermore, a fifth aspect of the apparatus for achieving the second object is provided with an XY table control device for increasing or decreasing the moving speed of the XY table to which the substrate is fixed, as the control means.

According to the first aspect of the present invention, the present invention includes a nozzle for discharging a thick film paste onto a substrate, and a measuring device for measuring the film thickness of a thick film circuit formed on the substrate by the nozzle. Therefore, defects can be detected early and work can be completed, and loss time in the event of defects can be significantly reduced.

Furthermore, according to a second aspect of the present invention, there is provided a memory section that stores the film thickness measured by the above-mentioned apparatus, a calculation section that compares the film thickness, and a drawing condition that is changed by a command from the calculation section. Since the film is equipped with a control means, highly accurate film thickness management is possible, and the number of defects can be significantly reduced.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows the configuration of a drawing apparatus in a first embodiment of the present invention. In Fig. 1, 1 is a nozzle, 3 is a substrate height measuring device for measuring the distance to the substrate 2 (the glue in Fig. 1), 4 is the drawn thick film paste, and 5 is the distance to the thick film paste 4. fi (L2 in FIG. 1); 6 is a head that can move the nozzle 1 up and down independently of the film thickness measuring device 5 and the prism 12; a substrate height measuring device 3; The head 6 is moved up and down by an amount equal to the increase or decrease in the measured value L2, thereby keeping the distance between the nozzle 1 and the substrate 2 constant. The nozzle 1 applies a thick film paste 4 onto the substrate 2.
For example, it is a device that discharges liquid from the tip hole of a nozzle 1 using pressure.

The substrate height measuring device 3 and the film thickness measuring device 5 are distance measuring devices using lasers. For example, Anritsu Hikari Micro (M5
32A, restart range ±800 (μII) may be used.

In addition, measuring devices based on other principles, such as height measuring devices using ultrasonic waves, are also possible. The thick film paste 4 can be any type of paste, such as a conductor or a resistor. (For conductors,
For example, DuPont, A, /P, paste, #6134)
. The substrate 2 may also be of any type, such as a ceramic substrate or a glass-evo substrate. With the above configuration, the measured value of the substrate height measuring device 3 is the height of the thick film paste immediately after drawing. Measured value L of film thickness measuring device 5
The difference, L, -L2 is calculated and drawn while comparing it with the set film thickness.

However, if a conventional spring release is used for the initial setting of the nozzle as shown in FIG. 10, the rigidity of the head 6 decreases and the position (height) accuracy is lost. As shown in FIG. 5, a nozzle height detection stand 7 is provided at a position independent of the substrate 4, having a surface at the same height as the substrate height and a relief portion on the lower surface. The surface of the nozzle height detection table 7 has high accuracy, for example, by setting the parallelism to the tip of the nozzle 1 to 3 (ull). Furthermore, even when the nozzle height detection table 7 is pushed in, the guide 8 and the like prevent the surface from being tilted, making accurate measurement possible. Furthermore, in order to improve the accuracy of the position (height), in this embodiment, the conventional head 6
Instead of the method of drawing by moving the side, it was decided to move the side of the substrate 2.

In addition, in order to maintain high accuracy as mentioned above, the nozzle 1 does not rotate but moves only in the vertical direction (so the substrate height measuring device 3
Another problem is how to install the film thickness measuring device 5. Therefore, in this embodiment, as shown in FIG. 6, the distance measuring device is installed so that it can rotate around the nozzle 1, and is rotated so that the horizontal spot is always located in front and behind the nozzle 1. This makes it possible to measure film thickness in real time. However, there was a problem with the installation space due to the size of the distance measuring device, but as shown in Figure 7, the prism 1
This problem was solved by bending the optical path by 90 degrees using 2. Moreover, the problem of large inertia was solved by making the rotating wheel 9 shown in FIG. 6 hollow and using aluminum to reduce the weight, thereby maintaining the permissible accuracy range. Furthermore, there was a problem with how to handle the power cord of the distance measuring device, but as shown in FIG. 10 (for example, Slide Pack, manufactured by THK) moves and constantly eliminates slack in the cord, allowing the distance measuring device to rotate smoothly at high speed.

(Only one side of the mechanism is shown in Figure 6.) Additionally, if the film thickness exceeds the allowable range, an alarm will sound and the machine will automatically stop.

According to this embodiment, the process is as shown in Fig. 2, and defects can be found during the drawing process, so that when a drawing defect occurs, a part of the drawing process, drying, sample sampling, and film thickness measurement steps are eliminated. , it is possible to significantly reduce loss time.

FIG. 3 shows the configuration of a drawing apparatus in a second embodiment of the present invention.

In this figure, the same parts as those in FIG. 1 are given the same numbers, and their explanations will be omitted.

The difference between this figure and FIG. 1 is that the measured film thickness value -L2 is taken into the film thickness calculation section 13, and fed back to the movement of each actuator to reach the set film thickness value through the following control devices. This is the point. The film thickness calculation unit 13
It has data on the relationship between discharge pressure and film thickness, and has a discharge rate control device e.
The film thickness can be controlled by raising and lowering the discharge pressure via 14.

The film thickness calculation unit 13 also has data on the relationship between the gap amount between the tip of the nozzle 1 and the substrate 2 and the film thickness, and has data on the relationship between the film thickness and the gap between the tip of the nozzle 1 and the substrate 2. By changing the height of the nozzle 1 through the gap 15, the film thickness can be controlled by changing the size of the gap. Furthermore, the film thickness calculation section 13 also has data on the relationship between the drawing speed (speed of the XY table 16) and the film thickness, and the XY table control device 17
The film thickness can be controlled by changing the drawing speed through the .

In the film thickness management described above, data for each paste was created by taking into account 40 types of thick film pastes and their characteristics such as viscosity.

In addition, in terms of discharge pressure, if residual pressure remains during exhaust, the discharge will be excessive, so consideration should be given to ■minimizing the internal volume of the air system as much as possible, and ■removing parts that tend to leave residual pressure, such as mufflers, in the exhaust circuit. do. Furthermore, in terms of head height control, if a piezoelectric actuator is used, for example, minute movements can be easily controlled. In addition, in XY child table control,
Using vector velocity, type of line (III line, curve, etc.)
It is now possible to draw under the same conditions regardless of the situation.

Further, the priority order of the above-mentioned controls can be determined arbitrarily by the user, and each control can be used in combination.

Therefore, according to this embodiment, the process is as shown in FIG. 4, and in addition to the effects of embodiment 1, it is possible to control the film thickness with high accuracy, and the number of defects can be significantly reduced.

Effects of the Invention According to the first aspect of the present invention, the present invention includes a nozzle for discharging a thick film paste onto a substrate, and a measuring device for measuring the film thickness of a thick film circuit formed on the substrate by the nozzle. As a result, defects can be detected early and work can be completed, and loss time in the event of defects can be significantly reduced.

Furthermore, according to a second aspect of the present invention, there is provided a memory section that stores the film thickness measured by the above-mentioned apparatus, a calculation section that compares the film thickness, and a drawing condition that is changed by a command from the calculation section. Since the film is equipped with a control means, highly accurate film thickness management is possible, and the number of defects can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a drawing apparatus in a first embodiment of the present invention, FIG. 2 is a flowchart of the electronic circuit forming process in the first embodiment of the present invention, and FIG. 3 is a diagram of a second embodiment of the present invention. FIG. 4 is a flowchart of the electronic circuit forming process in the second embodiment of the present invention, FIG. 5 is a schematic diagram of the nozzle height detection stand, and FIG. 6 is a schematic diagram of the nozzle height detection stage. 1, a schematic diagram showing the positional relationship between the substrate height measuring device 3 and the film thickness measuring device 5, and a code processing method of the height detection stage 2, etc., FIG. 7 is a schematic diagram showing the optical path by the prism 12, and FIG. FIG. 9 is a block diagram of a conventional drawing device, FIG. 9 is a flowchart of a conventional electronic circuit forming process, and FIG. 10 is a schematic diagram of a conventional nozzle height detection device. 1...nozzle, 2...substrate, 3...
...Substrate height measuring device, 4...Thick film paste,
5...Film thickness measuring device, 6...Head, 7
...Nozzle height detection stand, 8...Guide, 9...Wheel, 10...Slider, 11...Protrusion, 12. ·····prism,
13...Film thickness calculation unit, 14...Discharge amount control device, 15...Head height control device, 16
...XY child table 17...XY table control device. 1-1・Nos”le 2…(Salesy-11 Enoki Atsushi Ryūei C-・-Herap Agent's name Patent attorney Shigetaka Awano and 1 other person) Part 7---Nos 11 Ka One tip of the rod is 3--one force ゛4V Fig.

Claims (5)

[Claims] (1) A nozzle for discharging thick film paste onto a substrate, and a measuring device for measuring the thickness of a thick film circuit formed on the substrate by the nozzle, and the measuring device measures the height of the substrate. A thick film circuit forming apparatus comprising means for calculating film thickness by taking the difference between a measurement value obtained by a measurement device that measures the height of a thick film circuit formed on a substrate and a measurement value obtained by a measurement device that measures the height of a thick film circuit formed on a substrate. (2) a memory unit that stores the measured film thickness; a calculation unit that compares the film thickness with a set film thickness; and a control unit that changes the thickness of the drawn thick film paste based on instructions from the calculation unit. The thick film circuit forming apparatus according to claim 1, comprising: (3) The thick film circuit forming apparatus according to claim 2, further comprising a discharge amount control device that increases or decreases the discharge amount of the thick film paste from the nozzle as the control means. (4) A head height control device according to claim 2, characterized in that the control means is provided with a head height control device that increases or decreases the height of the head supporting the nozzle in order to increase or decrease the distance between the nozzle and the substrate. Thick film circuit forming equipment. (5) The thick film circuit forming apparatus according to claim 2, further comprising an XY table control device for increasing or decreasing the moving speed of the XY table to which the substrate is fixed as the control means.