JPS58145193A - Low temperature operating circuit board mounting structure - 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 The present invention relates to a structure of a circuit board and a housing in which a large number of these circuit boards are installed, and particularly to a structure that can be cooled to a low temperature and operated without error.

In information devices such as computers, high-speed operation is required, and circuits are becoming more dense and highly integrated.However, silicon integrated circuits and other devices have limitations due to their materials, and currently microfabrication technology is not available. Efforts are being made to find a way out. However, on the other hand, as another direction to overcome the above-mentioned limitations, circuit elements that operate at high speed when cooled to extremely low temperatures have been developed. For example, the Josephson element is It is known that the device operates at ultra-high speed and consumes very little power.
M T (Ejgh Elaotron Mobili
ty Transistor) is an element with a new operating mechanism, which also operates at a low temperature, that is, liquid nitrogen (N2) temperature (7
This is a device that operates at high speed (7K).

There is a strong possibility that miniaturized ultra-high-speed computers will appear in the near future with elements such as those mounted at high density, and it is therefore essential that electronic circuit boards be kept at low temperatures to operate reliably. Become.

By the way, existing circuit boards and the casings in which they are mounted are designed to operate mainly at room temperature.
Unable to cope with severe temperature cooling, the connection between the circuit board and the case (connector) may become disconnected due to heat shrinkage, making it impossible to operate, or even if it does not come off, contact resistance increases. High speed operation will be impaired.

Therefore, the mercury contact method has long been used as a connection method for cases where there are large temperature changes, but it is difficult to create a fine, high-density structure for high-speed operation, the structure is weak, and mercury is also a material. It is also poisonous.

(d) Purpose of the Invention The present invention eliminates the above-mentioned problems and proposes a high-density mounting circuit board and its housing structure that can be operated at low temperatures and at high speeds.

(0) Structure of the Invention The object of the invention is that the outer plate of the casing parallel to the circuit board is made of a material that has a larger temperature shrinkage than the circuit board, and the four-way board is perpendicular to the outer casing plate. Circuit paper board mounting having a tapered shape, on which a connection lead is provided, a clamping surface inside the casing that clamps the lead also having a tapered shape, and a lead end facing the connection lead mentioned above is provided on the clamping surface. This can be achieved through structure.

(f) Examples of the invention Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a circuit board 1 according to the present invention and a casing 2 equipped with the circuit board 1. The circuit board 1 is made of a material with small temperature contraction.
For example, it is formed of a ceramic substrate, on which low-temperature operation electronic components (not shown) such as Josephson elements or HEMT elements are mounted, and both ends IT thereof are tapered on both sides. This circuit board 1 is supported by a housing outer plate 8 perpendicular to the circuit board 1, and is held between two-shaped support portions that fit on both sides of the tapered board. The outer envelope plate 4 of the sieve body 2, which is parallel to the circuit paper board 1, is made of a material having a large temperature shrinkage, such as a Teflon plate.

With this structure, the circuit board 1'Fr can be inserted into the housing 2 at room temperature, but if it is cooled to 4K or 77 - during operation, the outer envelope 4 will shrink significantly and the circuit will be damaged. ; Since the plate 1 has a small shrinkage, a large pressure is generated on the supporting portion. Therefore, as shown in the cross-sectional view of the support part shown in FIG. 2, connection leads 5 made of a thin or thick film of gold or copper are formed on the surface of the circuit board 1, and the lead ends 6 made of the same material are formed in contact with the connection leads 5. It is provided on the outer envelope plate 8 of the housing 2 and when brought into contact forms a connection suitable for low temperature operation. In this case, compared to the length of the outer cover plate 4 of the housing 2, the outer cover plate 8 supporting the circuit board l is
The width between the circuit boards is sufficiently small, for example, if the length of the outer plate 4 is 20Q and the width between the circuit boards is about a few inches,
Shrinkage of the outer envelope plate 8 does not pose much of a problem.

FIG. 8 shows a partial plan view of the circuit board 1. At the tapered side end IT, the width of the connection lead 5 is set to about several lOμ78, which is wider than the wiring width on the board surface, so that the contact resistance is made as small as possible. In order to mount component elements on such a circuit board 1, in addition to a low-temperature substrate, a silicon substrate,
An epoxy resin plate or the like is suitable.

In addition to the above-mentioned Teflon, nylon is a suitable material for the outer envelope plate 4, which can be greatly shrunk to strengthen the contact pressure.The table below shows the humidity shrinkage rate compared to other materials. , Teflon is also a material that is resistant to temperature changes such as rapid cooling.

(g) Effects of the Invention As can be seen from the description of the embodiments above, the present invention has a structure that uses thermal contraction at low temperatures to reduce the contact resistance of the connection part, and has a very simple structure. It forms fine patterns and is ideal for high-density circuit configurations.

Therefore, the present invention enables the operation of ultra-high-speed computers.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the circuit board and the casing, FIG. 2 is a sectional view of the supporting portion of the circuit board, and FIG. 8 is a partial plan view of the circuit board. In the figure, ■ is a circuit board, 2 is a sieve, 3 is an outer plate perpendicular to the board, 4 is an outer plate parallel to the board, 5 is a connection lead,
6 indicates a lead end, and IT indicates a side end of the circuit board. Agent Patent Attorney Hiroshi Matsuoka Department 1 Figure 2

Claims (1)

[Claims] In a case in which a circuit board is mounted, an outer wall plate parallel to the circuit board is made of a material that has a larger temperature shrinkage than the built-in circuit board, and the outer wall board is perpendicular to the circuit board. The supported surface of the circuit board is tapered, and connection leads are provided on that surface, and the clamping surface in the casing that clamps it is also tapered, and the connection leads are provided on the clamping surface. A circuit board mounting structure for low-temperature operation characterized by having a lead end that contacts the lead.