JPS62185392A - Ceramic circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a ceramic substrate that can be used in the mass production of consumer devices equipped with electronic circuit components, such as radio receivers and television receivers. be.

Conventional technology In recent years, as electronic devices have become smaller and lighter, electronic circuits have been increasingly mounted in high density, and ceramic substrates, typically alumina substrates, have come to be used more and more as substrates. ing.

On the other hand, the structure has also shifted from single-sided mounting to double-sided mounting, and has also shifted to multi-layered mounting.

Furthermore, the conductor materials have changed from precious metal materials such as gold and silver-palladium, which are fired in the air, to base metal materials, which are fired in a neutral atmosphere, such as Ido. .

To form a circuit on such a ceramic substrate, conductors are printed on one or both sides of a white ceramic board. At the same time, form through-holes that are necessary at that time. Next, a noble metal material is fired in air, and a base metal paste is fired in a neutral atmosphere to form a conductor line. Next, a resistor material is printed and fired in the same manner. Furthermore, the resistor is trimmed to a desired resistance value, glass printed, and fired to form a passivation film. Finally, solder printing is performed, and the components are mounted and soldered to form an electronic circuit.

Problems to be Solved by the Invention However, when performing double-sided printing and through-hole printing in the production process of such ceramic circuit boards, it is inevitable that the suction holes for holding the board and the suction holes for forming through balls are the same. The actual situation is that this creates a suction-type path, causing instability in through-hole formation.

Furthermore, when using copper conductors that require firing in a neutral atmosphere, due to their nature, oil stains such as hand marks that adhere to them during handling remain in the form of carbon, resulting in dark stains on the board and, in extreme cases, damage to the resistance. This was the main cause of body variation.

In addition, this thick film circuit board can be used for satellite communication, etc.
It is also used as a high frequency block in the GI4 band,
In that case, it is necessary to form a back ground due to the electrical characteristics, and in that case, a conductor is required to extend to the edge of the back surface, and it is required that the printing should not extend around the edge. Ru. This is because the adhesion of the conductor to the end face generates unnecessary inductance and capacitance components, which adversely affect the characteristics of the high frequency circuit.

The present invention solves these conventional problems and provides an excellent ceramic circuit board that has a simple structure and solves the above problems.

Means for Solving the Problems In the ceramic circuit board of the present invention, a circuit board section for actual use is provided in an arbitrary range on the board, and an appropriate margin section is provided around the circuit board section or on one pair of sides.

Function: The ceramic circuit board of the present invention is provided with an appropriate margin around the circuit board in actual use or on one pair of sides. ■ Adsorption holes are formed to attract the board to the margin when printing conductors or resistors. etc. can be provided independently,
The suction pressure for the suction holes used to form through-holes in the actually used parts can be changed independently, allowing stable printing of the inner walls of through-holes.

■ This blank area can be held by hand as a handling area during work, which not only allows for more efficient work, but also eliminates the risk of contaminating the circuit board since the part of the circuit board that is actually used is not touched by hand.

(2) By forming test patterns such as test patterns for resistor printing or fine patterns in this blank area, it can be used for reliability tests of resistors, trimmer experiments, etc.

(2) Furthermore, when forming the back ground electrode, by printing including this margin, the conductor can be printed up to the edge part in a circuit for actual use, and the conductor printing does not wrap around the end surface.

EXAMPLE Hereinafter, a ceramic circuit board according to an example of the present invention will be explained with reference to the drawings.

As shown in FIG. 1, in this example, a ceramic circuit board is prepared in which a margin part 2 of an appropriate area is provided around a circuit part 1 for actual use. Here, 3 is a conductor and 4 is a through hole.

Next, as shown in Fig. 2, suction holes 6 for the through holes 4 of the circuit section 1 in actual use and suction holes 5 for suctioning the peripheral margins 2 are independently installed on the printing press stand (for example, a new long A substrate with a margin 2 was attached to MS-150TN) 7, and a circuit pattern was printed thereon. (The material for the circuit board is 96-At203 through hole diameter 0.
．． Use a 6mφ board.

The conductor material was printed using DuPont's 9163D (Cu paste). At that time, the suction pressure of the through hole was 5 KP/i. Also, the substrate suction part is 2 Ky
It was adsorbed at a pressure of /oi.

Next, after drying, the circuit on the back side was printed under the same conditions, dried to form a pattern, and then placed in an electric furnace in a chino atmosphere at a maximum temperature of 900°C for 10 minutes.

The entire process took 60 minutes to bake. Thereafter, conductivity was checked on both sides, and all through holes 4 showed good conductivity.

Further, as a result of observing the condition of the through holes 4 through a microscopic examination, they were all in good condition.

On the other hand, as shown in FIG. 4, a printing machine stand (for example, New Long MS-15GT) 7' that uses a common hole 10 for the substrate suction holes and through-hole suction holes and performs suction at the same time is used, and the circuit pattern is printed in the same manner. was formed. First, increase the suction pressure to 6
A through hole was formed by suction at 9/ad. Thereafter, firing was completed under the same conditions as above, and a continuity check was performed.

As a result, two had poor continuity. Further microscopic examination revealed that the conductive paste on the front and back sides was clearly uneven, with some not being connected, and some through-holes being thicker than necessary.

During this series of work, I held the blank area of the board directly with my hand. As a result, when we looked at the state of the surface after sintering, we could clearly see black fingerprints in the areas where the hands had touched it.

Next, as shown in step 31, test patterns of conductors and resistors were formed in the blank area 2 other than the actual circuit portion 1.

Next, a butter 73 for a high frequency circuit was formed on the actual circuit portion 1. The state of the apricot is shown in Figure 3. The circuit pattern 3 was formed on the front surface (top surface in the drawing) as in the previous example, and then the entire surface ground section 3' on the back surface was printed and fired so as to cover the peripheral margin section 2. Next, a circuit for actual use was formed by breaking the blank area 2 from the boundary between the area where the ground pattern 3' was formed and the area where the ground pattern 3' was not formed. As a result, the back ground portion 3'
was formed up to the edge end face of the substrate, and did not wrap around to the end face.

Although this embodiment shows an example in which a blank space is provided around the periphery of the substrate, the same effect can be obtained even if the blank space is provided on some sides.

Effects of the Invention As described above, according to the present invention, in a double-sided printed, through-hole formed board, a blank area is provided on at least one pair of sides other than the actual circuit area, and the board suction holes are formed independently in the blank area around this area. By providing this, through-hole formation can be performed stably.

Furthermore, by touching the surrounding blank area with their hands, the operator does not have to use unnecessary nerves, and the ceramic circuit board can be formed quickly and without contaminating the actual circuit portion.

Next, by forming the basic characteristics of the thick film material in the peripheral margins, test pieces can be created using the same substrate and under the same conditions, allowing for more reliable reliability tests. Additionally, there is no need to create new test patterns, which can reduce unnecessary costs and time.

Next, if you need to ground the entire back surface of a high-frequency circuit board, etc., and you do not want to attach the conductor to the end surface, you can easily and reliably do this by printing and firing the conductor with it extending to this margin, and then breaking it. A substrate satisfying the above conditions can be formed.

[Brief explanation of drawings]

Fig. 1 is a plan view of a ceramic circuit board according to an embodiment of the present invention, Fig. 2 is a sectional view when printing when the through-hole suction hole and board suction hole are separated, and Fig. 3 is a back conductor. A cross-sectional view of the circuit board when formed on the entire surface, No. 4
The figure is a sectional view at the time of printing when the through-hole suction hole and the substrate suction hole are combined into one. 1...Actual use circuit board part, 2...Remaining part, 3...Conductor, 4...Through hole, 6... - Substrate suction hole, 6...Through hole suction hole, 7...Printing machine stand. Name of agent: Patent attorney Toshio Nakao and 1 other person23
- Conductor 12 figure/-m-Stool, chant round base Tatsukuni, 54 No. 4 figure

Claims (1)

[Scope of Claims] (1) A ceramic circuit board characterized in that a blank area of an appropriate area is provided on the periphery or on one pair of sides other than the circuit portion for final actual use. (2) The ceramic circuit board according to claim 1, wherein the blank space is used as a substrate suction part during printing. (3) The ceramic circuit board according to claim 1, wherein the blank space is used as a handling area from printing to component mounting. (4) The ceramic circuit board according to claim 1, characterized in that a test pattern is formed in the blank area. (6) The ceramic circuit board according to claim 1, wherein the circuit portion is printed up to the margin.