JPH08330484A - Fixing structure of semiconductor element - Google Patents

Abstract

PURPOSE: To provide the unit structure of a semiconductor element and a cooler which is arranged to be easy to be incorporated into a device. CONSTITUTION: Stack units whose key parts are semiconductor elements la and 18 are welded and fixed on both sides of a fixing board 4. For the cord of each part, A and B, which show the parts belong to left side and right side, respectively, are added. Talking to the left side, an insulating spacer 3A, a conductor-cooler 2A, a semiconductor element 1A, a cooler 2A, and a insulating spacer 3A are stacked coaxially in this order on the left flank of the fixing board 4. Two pieces of poles 5A are erected, and a plate spring 6A laid between the left ends adds pressure to the stacked unit, according to the degree of fastening by a nut 7A at the center. This pressure is set to a recommended value for the thermally and electrically well conductivity between the semiconductor element 1A and each cooler 2A on both sides for the first reason and for maintenance of mechanical strength of the semiconductor element 1A for the second reason. In short, the pressure to the right stacked unit and that on the left side are generally different.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor element and a cooling element having electrical conductivity, which are coaxially laminated on both sides of a flat fixed substrate so as to be press-contacted and fixed to each other. Regarding the structure.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIG. FIG. 3 is a side view and FIG. 3B is a plan view of a conventional example. In the figure, two semiconductor elements 1 having a switch function and three cooling elements 2 having conductivity are alternately laminated, and the whole is pressure-bonded to one side of a fixed substrate 4 via an insulating spacer 3.・ Fixed. Here, the semiconductor element 1 is a cylindrical high-power electronic component incorporated in a power device such as an uninterruptible power supply and generates heat during operation. The cooling body 2 is a flat component corresponding to the generated heat and configured by arranging fins in parallel in the thickness direction, and has conductivity and also serves as a conductor. Generally, the cooling body 2 contacts and is arranged on one side or both sides of the semiconductor element 1. It should be noted that semiconductor elements, cooling bodies, and insulating spacers of different types (specifications and dimensions) are denoted by the same reference numerals 1, 2, and 3 for convenience of explanation as being functionally the same.

Further, the pressure contact and the fixing are based on the spring force. That is, the two stacked units such as the semiconductor element 1 and the cooling body 2 are vertically arranged on the fixed substrate 4 so as to sandwich the stacked unit from the left and right.
A bar 19 is bridged over the upper end surface of each column 5, a pressing screw 18 is provided at the center of the bar 19, and a coil spring 17 is inserted at the tip thereof. The lower end surface of the coil spring 17 comes into contact with the upper surface of the upper spacer 3, and a pressing force is applied to the whole by rotation of the pressing screw 18. Here, in order to have good thermal and electrical conductivity between the semiconductor element 1 and the cooling body 2, proper parallelism, flatness, and surface roughness of the contact surface, cleaning of the contact surface, and misalignment of the axis line. Take preventive measures, such as applying adhesive compound with heat conductivity and conductivity, and
Recommended values (upper limit and lower limit) of the applied pressure contact force are set in consideration of the mechanical strength of the semiconductor element. Therefore, the displacement of the spring 17 is adjusted via the pressing screw 18 so that the pressure contact force has a recommended value according to the types of the semiconductor element 1 and the cooling body 2 used here.

Although not shown here, when the laminated unit of the semiconductor element and the cooling body requires two different pressure contact forces depending on the type of the semiconductor element, the upper surface side of the fixed substrate. In addition, two of the same laminated units as described above are arranged in parallel in an upright position so that a separate pressure contact force can be applied to each laminated unit.

[0005]

In the conventional example, when two laminated units are required, they are arranged upright on the upper surface of the fixed substrate and an appropriate pressure contact force is applied to each of them. The size is large, which may be inconvenient when incorporated into the device. Therefore, there is a demand for a structure in which the semiconductor element and the cooling body are wholly easily incorporated into the device.

The problem to be solved by the present invention is to solve the above-mentioned problems of the prior art and to make it possible to easily assemble semiconductor devices and conductive cooling bodies by laminating and pressing them into a device. It is to provide a fixed structure for a semiconductor device.

[0007]

DISCLOSURE OF THE INVENTION The present invention is directed to a flat fixed substrate having one or more flat semiconductor elements on each side thereof and a conductive flat type contacting at least one side of each semiconductor element. The cooling bodies are stacked coaxially, and pressure welding is performed by the force according to the common recommended pressure welding value for each semiconductor element.
It is fixed.

Further, according to the present invention, the means for press-contacting / fixing is a leaf spring fixed / supported by a pillar standing on each side of the fixed substrate, or a leaf spring of the pillar on each side. It is preferable to be fixed and held by the mounting frame at a total of two locations located outside.

[0009]

According to the present invention, the semiconductor element and the cooling body are coaxially laminated on each side of the fixed substrate, and the semiconductor element and the cooling element are pressure-contacted and fixed with a force according to the common recommended pressure-contact value for each semiconductor element. The element has a mechanically sufficient strength to ensure good thermal and electrical conductivity with the cooling body, and also becomes a rod-shaped unit as a whole.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fixed structure for a semiconductor device according to the present invention will be described below with reference to the drawings. FIG.
FIG. 3 is a side view of the first embodiment showing the basic configuration. FIG.
In the above, the laminated units having the semiconductor elements 1A and 1B as main parts are pressed and fixed to both sides of the flat fixed substrate 4, respectively. It should be noted that A and B are added to the respective parts after the common numeral symbols indicating the parts themselves, as they belong to the left side and the right side. The left side of the fixed substrate 4 will be described as a typical example.
A, a conductive cooling body 2A (that is, also serving as a conductor), a semiconductor element 1A, a cooling body 2A, and an insulating spacer 3A are coaxially laminated in that order. Two columns 5A having nuts 7A threaded at their ends are erected on the left side surface of the fixed substrate 4 so as to be located on the upper and lower sides of this laminated unit. At the central portion of the leaf spring 6A spanned between the left ends of the columns 5A, a pressure contact force is applied to the laminated unit according to the degree of tightening by the nut 7A, and this is pressure contacted / fixed to the fixed substrate 4.

As described above, this pressure contact force is due to the heat generated between the semiconductor element 1A and the cooling bodies 2A on both sides.
In order to provide good electrical conductivity, it is determined to have a recommended value by adjusting the tightening of the nut 7A in order to maintain the mechanical strength of the semiconductor element 1A. In other words, the pressure contact force on the laminated unit on the left side and that on the right side are generally different. In addition, in this first embodiment,
Although one semiconductor element 1A is sandwiched from both sides by two cooling bodies 2A, either one of the left side and the right side is cooled depending on the relationship between the heat generation amount of the semiconductor element 1A and the cooling capacity of the cooling body 2A. Sometimes body 2A alone is sufficient.

FIG. 2 is a side view of the second embodiment having a practical arrangement. In FIG. 2, with respect to the fixed substrate 4 located slightly to the right of the center, a laminated unit of semiconductor elements, a cooling body and other members is provided on each of the left and right sides and the leaf springs 6A and 6B.
Fix with the corresponding recommended pressure contact force via. The structure of the laminated unit is essentially the same as that of the first embodiment. That is, in terms of the left side, the number of semiconductor elements 1A that generate heat is 4
There is one, and the cooling bodies 2A are arranged on both sides except one on the left side. Since only one on the left side has a relatively small amount of heat generation, the cooling body 2A is arranged only on the left side. The two semiconductor elements 9A that do not generate heat are attached to the outer peripheral surface of the conductor 8A by screwing. On the right side, there are two semiconductor elements 1B that generate heat, and the cooling bodies 2B are arranged on both sides of each of them. In addition, 1 of the semiconductor element 9B that does not generate heat
The individual pieces are attached by screwing onto the outer peripheral surface of the conductor 8B. It should be noted here that the columns 5A and 5B, which are erected on the left side surface and the right side surface of the fixed substrate 4, respectively, have the leaf springs 6A and 6B in the vicinity of the respective end portions thereof and the corresponding nuts 7.
It was made by forming a U-shaped plate-shaped member, which is held at the position adjustable via A and 7B, and is fixed to the power device side at both side ends located outside each leaf spring 6A and 6B. It is attached to each leg of the mounting frame 10 so as to be sandwiched by two sets of nuts 7A and 7B.

[0013]

According to the present invention, the following excellent effects can be expected. (1) On each side of the fixed substrate, the semiconductor element and the cooling body are coaxially stacked and pressed and fixed, so that two of the laminated units of the semiconductor element and the cooling body form one fixed substrate sandwiching the fixed substrate. It can have a rod-shaped structure. Therefore, it is generally easy to incorporate in the device. (2) Since each pressure contact force on both sides has a recommended value common to each corresponding semiconductor element, the semiconductor element on each side has mechanically sufficient strength, and the thermal Electrical conductivity is secured. (3) Since the means for pressure contact / fixing is a leaf spring fixed / supported by the column of the fixed substrate, structural simplification is supported. (4) Since the structure can be securely and easily fixed and held to the mounting frame at a total of two locations located outside the leaf springs of the columns on each side as one unit, it can be incorporated into the device. Support ease.

[Brief description of drawings]

FIG. 1 is a side view of a first embodiment according to the present invention.

FIG. 2 is a side view of the second embodiment.

FIG. 3A is a side view and FIG. 3B is a plan view of a conventional example.

[Explanation of symbols]

 1A, 1B Semiconductor element 2A, 2B Cooling body 3A, 3B Insulation spacer 4 Fixed substrate 5A, 5B Post 6A, 6B Leaf spring 7A, 7B Nut 8A, 8B Conductor 9A, 9B Semiconductor element 10 Mounting frame

Claims (3)

[Claims] 1. A flat fixed substrate is coaxially laminated on each side thereof with one or more flat semiconductor elements and a flat cooling body having electrical conductivity in contact with at least one side of each semiconductor element. A fixed structure for a semiconductor element, which is press-contacted and fixed by a force according to a common recommended pressure-contact value for each semiconductor element. 2. The fixed structure according to claim 1, wherein the means for press-contacting / fixing is a leaf spring fixed / supported by a pillar standing on each side of the fixed substrate. Fixed structure of semiconductor device. 3. The fixing structure for a semiconductor element according to claim 2, wherein the supporting structure is fixed and held by a mounting frame at a total of two positions outside the leaf springs of the columns on each side. body.