RU2456714C1 - Semiconductor article and workpiece for making said article - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: semiconductor article has two parallel flat ends meant for connection with electrodes, and a perpendicular side surface with several edges. The article is made from crystalline material with a layered structure, having cleavage planes between layers that are perpendicular to said parallel flat ends and has a polygon shape in the cross-section, parallel to said flat ends. The cleavage planes between layers of the crystalline material lie parallel to diagonals of the polygon.

EFFECT: article has high strength qualities with optimum combination of electrophysical and thermophysical properties.

8 cl, 10 dwg

Description

FIELD OF TECHNOLOGY

The invention relates to semiconductor technology and, more specifically, to semiconductor products of crystalline materials intended for thermoelectric devices based on Peltier and Seebeck effects, namely thermoelectric generators, cooling and heating devices.

BACKGROUND OF THE INVENTION

Semiconductor products are known, mainly for thermoelectric devices, having two essentially parallel flat ends intended for connection with electrodes, and a substantially lateral surface with several faces perpendicular to them, made of a crystalline material with a layered structure having cleavage planes between layers essentially perpendicular to the specified parallel flat ends, and having in cross section parallel to the specified flat ends, the shape of a polygon, in particular - rectangle (RU 2120684 C1, 1998). In these known semiconductor products, all cleavage planes between the layers of the crystalline material are located at angles of not more than 7 ° to the parallel side faces. Similar semiconductor products are also known in which the cleavage planes between the layers of the crystalline material are located at angles of not more than 10 ° to parallel side faces (WO 98/31056 A1, 1998, RU 2160484 C2, 2000).

These known semiconductor crystalline products are fragile and can crack along the boundaries of the layers of crystalline material passing along the cleavage planes, not only under the influence of thermal and mechanical stresses arising from the operation of thermoelectric devices, but also during transportation of products prior to their installation in thermoelectric devices and during assembly of thermoelectric devices. If cracking of these known semiconductor crystalline products having cleavage planes between layers of crystalline material perpendicular to the ends connected to the electrodes after assembly does not cause a significant deterioration in the operation of thermoelectric devices, then cracking of such products during transportation and assembly is unacceptable.

SUMMARY OF THE INVENTION

The present invention is the creation of semiconductor products, mainly for thermoelectric devices with high strength properties, as well as the creation of blanks for the manufacture of such semiconductor products.

This problem is solved in that in a semiconductor product, mainly for thermoelectric devices, having two parallel flat ends intended for connection with electrodes, and a side surface perpendicular to them with several faces, made of crystalline material with a layered structure having cleavage planes between the layers, perpendicular to parallel flat ends, and having in cross section parallel to flat ends, the shape of a polygon, according to the invention, the cleavage plane between the layer mi crystalline material are parallel to the diagonal of the specified polygon. This embodiment reduces the possibility of cracking of the semiconductor product and increases its strength.

Polygon angles located opposite the diagonal can be rounded. This embodiment further reduces the possibility of cracking of the semiconductor product.

The side surface of the semiconductor product may be free from destructive treatment and may be coated with electrical insulating material.

An electrically conductive coating may be applied to the parallel flat ends of the semiconductor product.

A workpiece for the manufacture of semiconductor products, mainly for thermoelectric devices, made of a crystalline material with a layered structure having cleavage planes between the layers, according to the invention is made in the form of a rod with a rectilinear axis, having a side surface with several faces and having a section perpendicular to the axis of the rod, the shape of the polygon, while the cleavage planes between the layers of crystalline material are parallel to the axis of the rod and parallel to the diagonal polygon.

The corners of the polygon located opposite its diagonal can be rounded.

The side surface of the workpiece may be coated with electrical insulating material.

Further, the present invention is disclosed in exemplary embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The attached drawings show:

Fig. 1 is a side view of a first embodiment of a semiconductor product according to the present invention;

figure 2 is a section aa in figure 1;

figure 3 is a side view of a second embodiment of a semiconductor product according to the present invention;

figure 4 - section bb in figure 3;

figure 5 - blank for the manufacture of a semiconductor product according to the present invention, the first option is a General view;

figure 6 is a section CC in figure 5;

7 is a blank for the manufacture of a semiconductor product according to the present invention, the second option is a General view;

on Fig - section D-D in Fig 7.

figure 9 is a form (container) for receiving the workpiece shown in figure 5, in longitudinal section;

figure 10 is a section EE in figure 9.

MODES FOR CARRYING OUT THE INVENTION

The semiconductor product 1a shown in FIG. 1 (the first embodiment), intended for thermoelectric devices (not shown), has two parallel flat ends 2 and 3 and a side surface perpendicular to them 4. The ends 2 and 3 are designed to connect to the electrodes of the thermoelectric device (not shown). In the cross section AA, parallel to the ends 2 and 3 (FIG. 2), the semiconductor product 1a has the shape of a polygon, namely a quadrangle (a square is shown in FIG. 2, however, the semiconductor product 1a in the cross section AA can have another shape, for example the shape of a rectangle with sides different in length, or a parallelogram, including a rhombus, are not shown in the drawings). The lateral surface 4 has four faces 5a, 5b, 5c, 5d.

The semiconductor product la is made of a crystalline material with a layered structure having cleavage planes 7a, 7b, 7c, 7d, 7e between layers 6a, 6b, 6c, 6d, 6e, 6f that are perpendicular to the ends 2 and 3 and are parallel to the diagonal 8 of the quadrangle, shown by the dashed line (figure 2) and passing between the corners 9a, 9c of the quadrangle. The other two corners 9b, 9d of the quadrangle, located opposite the diagonal 8, are rounded (figure 2). Figure 2 conventionally shows six layers of crystalline material from which the semiconductor product 1a is made, however, the number of layers of crystalline material may be different (not shown in Figure 2).

The lateral surface 4 of the semiconductor product 1a is free from destructive processing and is covered with a layer 10 of insulating material (figure 2). At the ends 2, 3 of the semiconductor product 1a, an electrically conductive coating 11a, 11b is applied.

The semiconductor product 1b (second embodiment) shown in FIG. 3, intended for thermoelectric devices (not shown), has two parallel flat ends 2 and 3 and a side surface perpendicular to them 4. Ends 2 and 3 are intended to be connected to the electrodes of the thermoelectric device (not shown). In the cross section BB, parallel to the ends 2 and 3 (FIG. 4), the semiconductor product 1b has the shape of a polygon, namely a hexagon. The lateral surface 4 has six faces 5a, 5b, 5c, 5d, 5e, 5f. The semiconductor product 1b is made of a crystalline material with a layered structure having cleavage planes 7a, 7b, 7c, 7d, 7e between the layers 6a, 6b, 6c, 6d, 6e, 6f that are perpendicular to the ends 2 and 3 and are parallel to the diagonal 8 of the hexagon, shown by a dashed line (Fig. 4) and passing between the corners 9a, 9d of the quadrangle. The remaining four corners 9b, 9c, 9e, 9f of the hexagon, located opposite the diagonal 8, are rounded (figure 4). Figure 4 conventionally shows six layers of crystalline material from which the semiconductor product 1b is made, however, the number of layers of crystalline material may be different (not shown in Fig. 4).

The side surface 4 of the semiconductor product 1b is free from destructive processing and is covered with a layer 10 of electrical insulation material (Fig. 4). At the ends 2, 3 of the semiconductor product 1b, an electrically conductive coating 11a, 11b is applied.

5, the blank 12a for manufacturing the first embodiment of the semiconductor product 1a is made in the form of a rod with a rectilinear axis 13. In the cross section CC, perpendicular to the axis 13 (Fig.6), the rod 12a has the shape of a polygon, namely a quadrangle (on 6 shows a square, however, the rod 12a in the cross section CC may have a different shape, for example a rectangle or a rhombus, not shown).

The rod 12a has a side surface 4 with four faces 5a, 5b, 5c, 5d (Fig.6). The preform 12a is made of a crystalline material with a layered structure having cleavage planes 7a, 7b, 7c, 7d, 7e between the layers 6a, 6b, 6c, 6d, 6e, 6f, which are parallel to the axis 13 and parallel to the diagonal 8 of the quadrilateral shown by the dashed line (Fig.6) and passing between the corners 9a, 9c of a quadrangle. The other two corners 9b, 9d of the quadrangle, located opposite the diagonal 8, are rounded (Fig.6). 6 conventionally shows six layers of crystalline material from which the preform 12a is made, however, the number of layers of crystalline material may be different (not shown in FIG. 6).

The lateral surface 4 of the workpiece 12A is covered with a layer 10 of electrical insulation material (Fig.6).

The blank 12b for manufacturing the second embodiment of the semiconductor product 1b shown in Fig. 7 is made in the form of a rod with a rectilinear axis 13. In a cross section D-D perpendicular to axis 13 (Fig. 8), the rod 12b has the shape of a polygon, namely a hexagon. The shaft 12b has a side surface 4 with six faces 5a, 5b, 5c, 5d, 5e, 5f (Fig. 8). The preform 12b is made of a crystalline material with a layered structure having cleavage planes 7a, 7b, 7c, 7d, 7e between layers 6a, 6b, 6c, 6d, 6e, 6f that are parallel to axis 13 and parallel to diagonal 8 of the hexagon shown by the dashed line (Fig. 8) and passing between the corners 9a, 9d of the hexagon. The other four corners 9b, 9c, 9e, 9f of the hexagon, located opposite the diagonal 8, are rounded (Fig. 8). On Fig conventionally shows six layers of crystalline material from which the semiconductor product 1b is made, however, the number of layers of crystalline material may be different (not shown in Fig. 8).

The side surface 4 of the workpiece 12b is covered with a layer 10 of electrical insulation material (Fig. 8).

Semiconductor products la, lb are made as follows.

First, preforms 12a, 12b are made from crystalline material, having a predetermined orientation of the material layers along the axes 13 and with respect to the diagonals 8.

To do this, use the container shown in Fig.9.

The container 14 is formed by two parts 14a, 14b having a joint along the plane 15 (Fig.9 and 10). In each part 14a, 14b of the container 14, recesses 16a, 16b are formed to form a cavity 16 having a cross-sectional shape corresponding to the cross-sectional shape of the workpiece 12a or 12b. To obtain the blank 12a, the recesses 16a, 16b have a triangular cross-sectional shape, as shown in FIG. 10, to obtain the blank 12b, the recesses 16a, 16b have a trapezoidal cross-section (not shown in the drawings).

In addition, in one part of the container 14, a recess is made forming a seed cavity 17, and in another part of the container, a recess is formed forming a gate channel 18 to which the loading cavity 19 is connected.

The size of the seed cavity 17 in the direction perpendicular to the plane 15 is much smaller than the dimensions of the cavity 17 in other directions, for example, when the thickness of the cavity 17 in the direction perpendicular to the plane 15 is 0.2 mm, its length in other directions is about 10 mm .

In the loading cavity 19 of the container 14 is placed the source material 21 to obtain the workpiece 12A or 12b. The container 14 is placed in a chamber (not shown in the drawings) in which the heaters 20a, 20b, 20c, 20d are located. The chamber is filled with an inert medium under atmospheric pressure. The temperature in the chamber is increased to a temperature higher than the melting temperature of the loaded material 21, as a result of which it melts and fills the cavity 16 and the seed cavity 17. Then, the temperature of the heaters 20a, 20b, 20c, 20d is changed so that the material crystallizes in the cavity 16 in the direction from the seed cavity 17 to the sprue channel 18 with a speed not exceeding 0.1 mm / min.

As a result, preforms 12a or 12b are obtained with a layered structure having cleavage planes between layers 6a, 6b, 6c, 6d, 6e, 6f that are parallel to axis 13 and parallel to diagonal 8 (FIGS. 2 and 8).

The lateral surface 4 of the blanks 12a, 12b without coating that can destroy the outer layer of crystalline material is coated with an insulating material 10. Then, the blanks 12a, 12b are cut perpendicular to the axes 13 into parts and an electrically conductive coating 11a, 11b is applied to the ends of these parts.

The described semiconductor products made from the described blanks have improved strength properties with an optimal combination of electrophysical and thermophysical properties.

INDUSTRIAL APPLICABILITY

The invention can be applied in thermoelectric generators, thermoelectric cooling and heating devices, as well as in measuring and other devices.

Claims (8)

1. A semiconductor product, mainly for thermoelectric devices, having two essentially parallel flat ends intended to be connected to the electrodes, and a substantially multi-faceted side surface perpendicular thereto, made of a crystalline material with a layered structure having planes cleavages between the layers, essentially perpendicular to the specified parallel flat ends, and having in cross section parallel to the specified flat ends, a polygon shape, characterized in that then the specified cleavage planes between the layers of crystalline material are located essentially parallel to the diagonal of the specified polygon. 2. The semiconductor product according to claim 1, characterized in that the corners of the specified polygon, located against the specified diagonal, are rounded. 3. The semiconductor product according to claim 1, characterized in that its specified lateral surface is free from destructive processing. 4. The semiconductor product according to claim 1, characterized in that its specified side surface is covered with an insulating material. 5. The semiconductor product according to claim 1, characterized in that said electrically conductive coating is applied to said parallel flat ends thereof. 6. A workpiece for the manufacture of semiconductor products, mainly for thermoelectric devices, made of a crystalline material with a layered structure having cleavage planes between the layers, characterized in that it is made in the form of a rod with a substantially rectilinear axis having a side surface with several faces and having in cross section perpendicular to the indicated axis of the rod, the shape of a polygon, while the specified cleavage planes between the layers of crystalline material are essentially count, parallel to said shaft axis and parallel to a diagonal of said polygon. 7. The workpiece according to claim 6, characterized in that the corners of the specified polygon, located opposite the specified diagonal, are rounded. 8. The workpiece according to claim 6, characterized in that its specified lateral surface is covered with an insulating material.

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