JP2005056980A - Integrated circuit with thermally sensitive elements insulated thermally from heat source and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a circuit sensitive to temperature change and a heat source to coexist in an integrated circuit area. <P>SOLUTION: A thermosensitive device 12a is shielded from a heat generating device 12b on a same integrated circuit 10 by providing an optimal trench 14a for insulating thermally the heat generating device 12b from the thermosensitive device 12a. In one embodiment, the trench 14b is formed by rear corrosion penetrating entirely an integrated circuit wafer. As a result, the trench 14b can be filled with an insulating material 18. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

(background)
The present invention generally relates to thermal insulation in integrated circuits.

  An integrated circuit may include various components. Some of these components may generate high heat. Another component may be relatively sensitive to high temperatures and changes.

  In order to keep costs low, it is desirable to integrate as many different components as possible in the same integrated circuit. This integration not only reduces costs, but also reduces the size. However, as more components are integrated, there is a higher probability that a heat sensitive device will be integrated with a high heat generating device.

  Thus, there is a need for a better way to integrate different types of devices on the same integrated circuit without causing problems related to heat.

(Detailed explanation)
In FIG. 1, integrated circuit 10 may include various integrated components. For example, a circuit or device sensitive to a temperature change may be arranged in the region 12a. For example, a heat generating device or circuit such as a power amplifier may be disposed in each of the regions 12b and 12c. In this way, it is desirable to thermally insulate region 12a from both regions 12b and 12c.

  For this purpose, a filled L-shaped trench 14a may be arranged around the edge of the region 12b. In this case, the two sides of the relatively square area facing the area 12a may be shielded by the filled L-shaped trench 14a. Region 12c may be insulated by a completely filled trench 14b. The trench 14 is effective for insulating the heat generating circuit regions 12b and 12c from the temperature sensitive circuit region 12a.

  In this manner, as shown in FIG. 2, the heating circuit 20 may be formed in the region 12 c of the integrated circuit substrate 10. The circuit 20 may be formed inside and on the surface of the semiconductor substrate 11. An upper surface dielectric layer 16 may be disposed on the substrate 11.

  In one embodiment of the invention, the trenches 14 are formed by back side etch from the back side of the substrate 11 while the circuit 10 remains in the form of a wafer. This backside corrosion may use the top dielectric layer 16 as an etch stop. Thus, in one embodiment of the invention, backside erosion extends completely through the wafer substrate 11 and reaches the etch stop dielectric layer 16 on the top surface of the wafer.

  The trench 14 is then filled with a suitable filler 1 having suitable thermal insulation properties. For example, amorphous silicon dioxide may be used as the heat insulating filler 1. In some embodiments, no trench fill is utilized. In another embodiment, the trenches 14 are made from the top surface of the wafer instead of the back surface using conventional isolation trench technology.

  As a result, it can be seen that harmful high temperatures or temperature fluctuations caused by devices with high power consumption, such as radio frequency power amplifiers, are further reduced when viewed from temperature sensitive devices coexisting on the same integrated circuit 10. .

  While the present invention has been described with respect to a limited number of embodiments, those skilled in the art can devise numerous modifications and variations therefrom.

  The appended claims are intended to cover all such modifications and variations that fall within the true spirit and scope of the invention.

  An integrated circuit is provided that includes a heat sensitive region, a heat generating region, and a trench disposed to shield the heat generating region from the heat sensitive region.

  The circuit of Example 1 is provided, wherein the trench is disposed in the vicinity of at least two sides of the heat generating region.

  The circuit of Example 1 is provided, wherein the trench completely surrounds the heat generating region.

  A circuit according to example 1 formed on a semiconductor substrate, wherein the trench extends completely through the substrate.

  The circuit of Example 4 is provided that includes a dielectric layer disposed on the top surface of the substrate.

  A circuit as in example 1 is provided that includes a trench filler disposed within the trench.

  The circuit of Example 6 is provided wherein the trench filler is amorphous silicon dioxide.

  The circuit of embodiment 1 is provided, wherein the circuit includes a semiconductor substrate, and the trench extends to enter the substrate from the back side of the substrate.

  The circuit of embodiment 8, wherein the trench extends from the back surface of the substrate and completely penetrates the substrate.

  The circuit of Example 9 is provided wherein the trench is filled with a thermal insulating filler.

  Generating a heat-sensitive first circuit in a first region of the integrated circuit; forming a second circuit generating heat in the second region of the integrated circuit; and generated by the second circuit Forming a trench around the second region to shield the first circuit from applied heat.

  The method of embodiment 11 is provided including the steps of forming the first and second regions on a semiconductor substrate and forming a trench extending completely through the substrate.

  The method of embodiment 12 is provided including forming a dielectric layer on the substrate and using the dielectric layer as an etch stop.

  A method according to example 13, comprising filling the trench with a trench filler.

  A method according to example 14 is provided, comprising filling the trench with amorphous silicon dioxide.

  The method of example 1 is provided including the step of forming the trench using backside erosion.

  A first region of the substrate including a semiconductor substrate, a heat-sensitive first element; a second region of the substrate including a second element that generates heat; the first region; And an integrated circuit comprising a trench extending completely through the substrate.

  The circuit of embodiment 17, wherein the substrate includes a top surface and a back surface, and the trench extends from the back surface to the top surface.

  The circuit of example 17 is provided including a dielectric layer provided on the substrate and the trench.

  The circuit of example 17 is provided wherein the trench is filled with a trench filler.

1 is a bottom plan view of an integrated circuit according to one embodiment of the present invention. FIG. FIG. 2 is an enlarged cross-sectional view cut substantially along the line 2-2 in FIG. 1 according to an embodiment of the present invention.

Claims (20)

Heat sensitive area,
A heat generation area;
An integrated circuit comprising: a trench arranged to shield the heat generating region from the heat sensitive region.   The circuit according to claim 1, wherein the trench is disposed in the vicinity of at least two sides of the heat generating region.   The circuit of claim 1, wherein the trench completely surrounds the heat generating region.   The circuit of claim 1 formed on a semiconductor substrate, wherein the trench extends completely through the substrate.   The circuit of claim 4 including a dielectric layer disposed on an upper surface of the substrate.   The circuit of claim 1, comprising a trench filler disposed in the trench.   The circuit of claim 6 wherein the trench filler is amorphous silicon dioxide.   The circuit according to claim 1, wherein the circuit includes a semiconductor substrate, and the trench extends to enter the substrate from a back surface of the substrate.   9. The circuit of claim 8, wherein the trench extends from the back surface of the substrate and completely penetrates the substrate.   The circuit of claim 9, wherein the trench is filled with a heat insulating filler. Forming a heat sensitive first circuit in a first region of the integrated circuit;
Forming a second circuit that generates heat in a second region of the integrated circuit;
Forming a trench around the second region to shield the first circuit from heat generated by the second circuit.   The method of claim 11, comprising forming the first and second regions on a semiconductor substrate and forming a trench extending completely through the substrate.   The method of claim 12, comprising forming a dielectric layer on the substrate and using the dielectric layer as an etch stop.   The method of claim 13, comprising filling the trench with a trench filler.   The method of claim 14, comprising filling the trench with amorphous silicon dioxide.   The method of claim 1, comprising forming the trench using backside erosion. A semiconductor substrate;
A first region of the substrate comprising a heat sensitive first element;
A second region of the substrate including a second element that generates heat;
An integrated circuit comprising: a trench disposed between the first region and the second region and extending completely through the substrate.   The circuit of claim 17, wherein the substrate includes a top surface and a back surface, and the trench extends from the back surface to the top surface.   The circuit according to claim 17, further comprising a dielectric layer provided on the substrate and the trench.   The circuit of claim 17, wherein the trench is filled with a trench filler.

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