JP2539593Y2 - Thick film printed circuit - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thick film printed circuit used for a hybrid IC or the like, and more particularly to a thick film printed circuit on which a conductive film covered with a glass film is printed for the purpose of protecting a circuit board surface.

[0002]

2. Description of the Related Art In a hybrid IC, for example, a conductor film or a resistor film formed in a desired pattern on a surface of a substrate made of ceramic or the like is protected from external influences and is insulated from each other. It is common practice to cover the substrate surface including the surface with a glass film. At this time, the electrode portion on which components such as chips are mounted and the electrode portion for joining the lead frame are not covered with the glass protective film.

According to the above-described thick-film printed circuit, the thickness of a conductor film, a glass film, and the like printed on a circuit board can be measured in a portion of the pattern which is not covered with the glass film before the component is mounted. However, when the components are mounted, there is no portion that is not covered with the glass film, so that there is an inconvenience in managing the circuit board after manufacturing such as inspection of all products and post inspection.

[0004]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, a main object of the present invention is to provide a thick film printed circuit which can easily measure each film thickness after mounting components. .

[0005]

According to the present invention, the above-mentioned object is to provide a thick-film printed circuit having a glass protective film for protecting a pattern such as a conductor film and a resistor film formed on a substrate surface. This is achieved by providing a thick film printed circuit, wherein the glass protective film is provided with a window exposing a part of the pattern and the substrate adjacent to the part.

[0006]

In this way, since the pattern and the substrate are exposed from the window provided in the glass protective film, for example, if a contact type film thickness measuring instrument is applied in this window, the pattern and the glass protective film can be obtained. Can be easily measured.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail below with reference to a specific embodiment, with reference to the accompanying drawings, in which: FIG.

FIG. 1 shows a hybrid I to which the present invention is applied.
The principal part top view of C is shown.

A conductive film formed on the ceramic substrate 1,
On the surface of the formation pattern 2 made of a resistor film or the like, portions other than the electrode portion region 3 on which the chip and the like are mounted and the electrode portion region 4 to which the lead frame is joined are covered with a glass protective film 5. The main component of this glass protective film is lead oxide (P
bO) and a film obtained by firing a glass paste made of a low-melting glass having a firing temperature of 500 ° C. to 550 ° C.
After firing this glass protective film 5, each of the electrode portion regions 3, 4
, And chip components (not shown), a lead frame, and the like are attached.

A window 6 is formed on the right side of the portion of the pattern 2 covered with the glass protective film 5 in FIG. 1 so that the surface of the ceramic substrate 1 and the pattern 2 are exposed.
That is, as shown in FIG. 2, there is a portion of the pattern 2 where the glass protective film 5 is not covered.

When measuring the film thickness of each film formed on the ceramic substrate 1 configured as described above, even after components (not shown) are mounted in the electrode regions 3 and 4, If a contact needle of a contact-type film thickness measuring device (not shown) is slid in the window 6, the film thickness of the pattern 2 and the glass protective film 5 can be easily measured.

The window 6 is provided with the glass protective film 5 of the pattern 2.
The same effect as that of the present embodiment can be obtained regardless of the portion on the ceramic substrate 1 as long as the portion is covered with.

[0013]

As is clear from the above description, according to the thick-film printed circuit of the present invention, only the window is formed,
Since the thickness of the pattern of the conductor film, resistor film, etc. and the glass protective film can be measured easily and at the same position after the components are mounted, a thick film printed circuit suitable for quality control without complicating the manufacturing process at all. Can be provided. In particular, since the inspection can be performed at any time as needed, it is very convenient for the user in quality control.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a hybrid IC to which the present invention is applied.

FIG. 2 is an enlarged sectional view taken along line II-II of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic substrate 2 Conductor film, resistor film 3, 4 Electrode area 5 Glass protective film 6 Window

Claims (1)

(57) [Scope of request for utility model registration] 1. A thick film printed circuit having a glass protective film for protecting a pattern such as a conductor film and a resistor film formed on a substrate surface, wherein the glass protective film includes a part of the pattern and A thick-film printed circuit comprising a window exposing the substrate adjacent to the portion.