JPH0839810A - Substrate for recording head and production thereof - Google Patents

Abstract

PURPOSE:To constitute a substrate for a recording head having a heating part high in heat conducting efficiency by forming a plurality of electrothermal conversion elements on the insulating film embedded in a semiconductor substrate and forming electrothermal conversion drive elements in the semiconductor substrate. CONSTITUTION:A layer composed of an Al material is deposited on a first conductive film 209 being a heating resistor layer composed of TaN in a specific thickness by a sputtering method to form a second conductive film 210. Continuously, Al and TaN are patterned to form electrothermal conversion elements and other wiring simultaneously. Next, an insulating film 213 composed of a P-Si film with predetermined thickness is deposited by a P-CVD method and an insulating film 214 composed of a PSG film with the specific thickness is further deposited by a atmospheric pressure CVD method. Next, the insulating film 214 on a heat accumulation layer 206 is etched by patterning to form aperture parts and, thereafter, a protective film 215 composed of Ta is deposited. The aperture parts 216 are operated as heating parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrothermal conversion element, a recording head substrate having an electrothermal conversion driving element formed on a substrate, and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 4 is a cross-sectional view showing a portion forming a conventional electrothermal converting element. An outline of the converting element will be described below with reference to the same figure.

After forming the N type epitaxial region 401,
The driving element 402 is formed inside, and the insulating film 403 is deposited. After that, patterning is performed to remove the insulating film 403 on the driving element 402 and deposit an insulating film 404. An opening for electrically connecting to the driving element 402 is provided by patterning, a metal material for the first electrode 405 is deposited, and the first electrode 405 is formed by a patterning process.

Next, the heat storage layer 406 is thickly deposited and patterned to form an opening 407 on the first electrode 405. Next, a metal material to be the heating resistance layer 408 and the wiring electrode 409 is deposited, the wiring electrode 409 is formed by patterning, and then patterning is performed to form the heating resistance layer 408.

After that, protective films 410 and 411 are successively deposited, and the protective film 411 other than the necessary portions is removed by patterning. In this way, the electrothermal converting element is formed, and the heat generating portion 412 is further formed.

[0006]

However, in the above-mentioned conventional example, since the heat storage layer 406 also serves as an interlayer insulating film between the first electrode 405 and the wiring electrode 409, it is necessary to increase the film thickness. Therefore, there is a drawback that it takes a long time to store and radiate heat. Further, the hole portion 4 for electrically connecting the first electrode 405 and the wiring electrode 409 to the heat storage layer 406.
When forming 07, since the film thickness of the heat storage layer 406 is large,
It is necessary to thicken the resist used as an etching mask at the time of patterning, it is difficult to form fine openings, and the reliability of the metal wiring is reduced, and at the same time, the metal wiring is disconnected due to the internal stress of the heat storage layer 406 itself. However, there is a problem in that the yield is significantly reduced.

In addition, the heating resistance layer 408 and the protective film 410
In the heat generating portion 412 formed by 411 and 411, the heat conduction efficiency is poor because the thickness of the protective film 410 is large.

The present invention solves the above-mentioned problems and forms a heat storage layer having a high heat conduction efficiency, and at the same time, enables formation of a wiring corresponding to a high degree of integration. An object of the present invention is to provide a recording head substrate that can be formed and a manufacturing method thereof.

[0009]

The above object can be achieved by the present invention described below. That is, the present invention provides a recording head substrate in which a plurality of electrothermal conversion elements are formed on an insulating film, and the electrothermal conversion driving elements for driving the electrothermal conversion elements are formed in a semiconductor substrate. The present invention discloses a recording head substrate, which is embedded in the semiconductor substrate.

Further, according to the present invention, a plurality of electrothermal conversion elements are formed on an insulating film, and each electrothermal conversion driving element for driving each electrothermal conversion element is formed in a semiconductor substrate. Also disclosed is a method for manufacturing a recording head substrate, characterized in that the insulating film is embedded in the semiconductor substrate.

The present invention has been made in view of the above technical problems, and at the same time as forming a heat storage layer having a high heat conduction efficiency, it is possible to form a wiring corresponding to a high degree of integration and a high heat conduction efficiency. Provided is a recording head substrate capable of forming a heat generating portion, and a manufacturing method thereof.
In particular, in a method of forming a heat storage layer and a heat generation layer by combining an insulating film and a conductive film, (1) a first step of providing an opening portion in a semiconductor substrate and burying a first insulating film; and (2) A second step of depositing a second insulating film on the first insulating film and the semiconductor substrate, and forming a second opening on the first insulating film by patterning; and (3) the third step. Forming a first conductive film and a second conductive film on the first insulating film and the second insulating film, and patterning the second conductive film from a part or the whole of the second opening. A third step of removing,
(4) A third insulating film and a fourth insulating film are deposited on the first conductive film, the second conductive film, and the second opening, and the second insulating film is patterned by patterning the third insulating film and the fourth insulating film. A fourth step of removing the fourth insulating film from a part or the whole, and (5) forming a protective film on the third insulating film and the fourth insulating film,
And a fifth step of removing a part of the protective film by patterning.

As described above, in the present invention, since the heat storage layer is formed in the semiconductor substrate, the heat transfer efficiency for heat storage and heat dissipation can be greatly improved. Further, in the present invention, since the interlayer insulating film can be formed thinly, fine through holes can be formed, and fine metal wiring can be formed. Therefore, it is possible to prevent disconnection of the metal wiring due to stress migration, and it is possible to form a highly reliable metal wiring. Furthermore, since the thickness of the protective film of the heat generating portion is reduced, the heat conduction efficiency of the heat generating resistor can be greatly improved.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings, but the present invention is not limited thereto.

Example 1 A first preferred embodiment according to the present invention is to provide a semiconductor substrate with a first opening, and embed a first insulator in the first opening to form a first insulator on the semiconductor substrate. After depositing a second insulating film on the first insulating film, patterning is performed to form a second insulating film only on the first insulating film.
Of the second conductive material is continuously deposited on the second conductive material, and only the second conductive material is formed from a part or all of the second conductive material. And further depositing third and fourth insulating films on the entire semiconductor substrate including the second opening, and removing only the fourth insulating film in the second opening by patterning. Then, the third opening is formed, and then the third conductive film is deposited on the entire semiconductor substrate including the third opening to form the electrothermal conversion element.

FIG. 1 is a drawing which shows the features of the present invention best. In FIG. 1, 101 is a semiconductor substrate, 102 and 102a are insulating films, 103 is a photosensitizer, 104 is a hole portion, and 105 is an insulating film. , 106 is an interlayer insulating film, 107 is an opening, 108 is a first conductive film, and 109 is the first of 108.
An opening covered with a conductive film, 110 is a second conductive film, 111
Is an insulating film, 112 is an opening covered with the insulating film of 111, 113 is an insulating film, 114 is an opening of the insulating film of 113, 115 is a protective film, and 116 is a protective film of 115. Represents an open hole.

The process flow shown in FIG. 1 will be described below step by step. First, the insulating films 102 and 102a are deposited on the semiconductor substrate 101, patterning is performed by a photolithography process, and a desired portion of the photosensitive agent 1 is formed.
03 and the insulating films 102 and 102a are removed.

In the present invention, the semiconductor substrate 101 is
An N-type epitaxial growth layer is formed, and the insulating film 102 is a SiN film formed by LP-CVD with a thickness of 200 n.
The thermal oxidation film 102a has a thickness of 50 nm (see FIG. 1A).

Subsequently, a photolithography process is performed by using a dry etching method to form the photosensitizer 103 and the insulating film 102.
As a mask, the semiconductor substrate 101 has a depth of 1.0 to
An opening 104 having a width of 3.0 μm and a width of 10 to 50 μm is formed. After forming the opening 104, the photosensitizer 103 is formed.
Is removed. Next, the insulating film 10 is formed in the opening (104).
Embed 5

In this embodiment, the dimensions of the opening 104 are 1.5 μm in depth and 20 μm in width, and the insulating film 105 is thermally oxidized to a thickness of 2 μm by a thermal oxidation (pyrogenic) method. A film is formed to fill the opening. After the thermal oxidation is completed, the insulating film 102 used as the mask is removed (see FIG. 1B).

Since the insulating film 102 is a SiN film, hot phosphoric acid is used for removal. In addition, in FIG. 1B, the number of the insulating film embedded in the opening is one, but a plurality of the insulating films can be arranged if necessary. The insulating film 105 formed here is used as a heat storage layer.

Next, an interlayer insulating film 106 is deposited on the semiconductor substrate 101 having a structure in which the insulating film 105 is buried. Then, patterning is performed by a photolithography process to form the opening 107. As the interlayer insulating film 106, a PSG film is deposited to a thickness of 700 nm by an atmospheric pressure CVD method, but in addition to this, an NSG film and a BPSG film are also deposited.
Film, P-SiN film by P-CVD method, P-SiO film,
The P-SiON film and the various insulating films described above are formed to a thickness of 100.
It can be compositely deposited in the range of up to 1000 nm.

The openings 1 are formed by patterning these films.
In the case where 07 is provided, a hole is formed on the insulating film 106 (see FIG. 1C).

Next, a first conductive film 108 is deposited on the patterned interlayer insulating film 106 and the opening 107. TaN having a thickness of 100 nm is deposited on the first conductive film 108 by a sputtering method. This TaN is used as a heating resistor (see FIG. 1D).

Subsequently, the second conductive film 110 is deposited on the first conductive film 108, and the second conductive film 110 in the opening 109 is removed by patterning. The second conductive film 110 is made of Al—Cu 5 by a sputtering method.
Although it is deposited to have a thickness of 50 nm, the film thickness can be increased or decreased in order to have a necessary resistance value, and further, the film quality is PureAl, Al-Si, Al-Si-Cu, Al.
-Cu-Ti or the like can be used (see FIG. 1 (e)). After that, patterning is performed again to remove unnecessary portions of the first conductive film 108.

Next, an insulating film 111 is deposited on the opening 109 and the patterned second conductive film 110. In this example, the P-SiN film is deposited to a thickness of 200 nm by the P-CVD method.
The P-SiON film can be deposited to the required film thickness. Here, the hole 109 becomes like the hole 112 (see FIG. 1F). Subsequently, another insulating film 113 is deposited on the insulating film 111.

In this example, PS by atmospheric pressure CVD method is used.
G film is deposited to a thickness of 800 nm, but NSG, B
PSG and these membranes can be used in combination. Then, the opening 112 is formed by patterning.
The insulating film 113 covering the inside is etched to form an opening 114 (see FIG. 1G).

Next, the opening 114 and the insulating film 1
A protective film 115 is deposited on 13. The protective film 115
Has Ta deposited to a thickness of 200 nm by a sputtering method. Reference numeral 116 denotes an opening covered with the protective film 115, which serves as a heat generating portion (see FIG. 1 (h)).

In this embodiment, the electrothermal conversion element is formed as described above. By embedding the heat storage layer (insulating film 105) of the electrothermal conversion element in the semiconductor substrate 101 as described above, the heat conduction efficiency is significantly improved, so that the heat storage / heat radiation cycle can be shortened. In addition, the insulating film 11 on the heating resistor (second conductive film 108: TaN)
Since the thickness of 1 (SiN film) is also thin, the heat conduction efficiency is improved also here, and by combining it with the heat storage layer 105, a synergistically high efficiency of heat conduction can be achieved. can do.

Further, since the interlayer insulating film 106 can be thinned, it becomes possible to apply a thin layer of resist etc. at the time of patterning when forming the metal wiring.
It is also possible to form fine metal wiring by increasing the resolution. Further, since the internal stress of the interlayer insulating film 106 itself is reduced, disconnection (stress migration) of the metal wiring can be suppressed, and the metal wiring with high reliability can be formed.

Embodiment 2 As a second embodiment of the present invention, a semiconductor substrate is provided with a first opening portion, a first insulator is embedded in the first opening portion, and a first opening portion is formed on the semiconductor substrate. After depositing the second insulating film, a plurality of second openings are formed only on the first insulator by patterning, and the first and second conductive portions are formed in the second openings. Material is continuously deposited, and only the second conductive material is removed from a part or all of the second opening portion,
Further, third and fourth insulating films are deposited on the entire semiconductor substrate including the second opening, and only the fourth insulating film in the second opening is removed by patterning. 3 holes are formed, and then a third conductive film is deposited on the entire semiconductor substrate including the third holes to form an electrothermal conversion element.

FIG. 2 is a drawing best showing the features of the second embodiment according to the present invention. In FIG. 2, 201 is a semiconductor substrate, 202 and 203 are insulating films, 204 is a photosensitizer, and 205 is an opening. , 206 is an insulating film, 207 is an interlayer insulating film, 208 is an opening, 209 is a first conductive film, 210 is a second conductive film, 211 is a stepped portion covered with the second conductive film 210, and 212 is An opening 213 from which the second conductive film 210 is removed is an insulating film that covers the second conductive film 210.
Reference numeral 4 denotes an insulating film which covers the entire surface, 215 a protective film, and 216 denotes an opening which is formed by removing the insulating film 214 and covered with the protective film 215.

The process flow shown in FIG. 2 will be described below step by step. First, the insulating films 202 and 203 are deposited on the semiconductor substrate 201, and patterning is performed to remove a desired portion of the photosensitive agent 204 and the insulating films 202 and 203 to form the opening 205. In this example, the semiconductor substrate 201 forms an N-type epitaxial growth layer, and the insulating film 202 is a thermal oxide film of 50 nm.
The insulating film 203 is formed to a thickness of S by the LP-CVD method.
The iN film is deposited to a thickness of about 200 nm (see FIG. 2A).

Subsequently, a dry etching method is used in a photolithography process, with the photosensitive agent 204 and the insulating film 203 as a mask, in the semiconductor substrate 201, a depth of 1.0 to 3.0 μm, a length of 10 to 50 μm, and a width of 500. ~ 2
An opening 205 having a diameter of 000 μm is formed. After forming this opening, the photosensitive agent 204 is removed.

Next, the insulating film 20 is formed in the opening (205).
6 is formed. In this embodiment, the dimensions of the openings are 1.5 μm in depth, 20 μm in length and 1500 μm in width, and the insulating film 206 is formed into a thermal oxide film having a thickness of 2 μm by the thermal oxidation method. The hole is embedded. After completion of this thermal oxidation, the insulating film 203 used as a mask
Are removed (see FIG. 2B). In this embodiment,
The insulating film 203 is a SiN film, and hot phosphoric acid was used for removal. Insulating film 206 formed here
Since it is used as a heat storage layer, a plurality of stages can be formed if necessary.

Next, an interlayer insulating film 207 is deposited on the semiconductor substrate 201 having a structure in which the insulating film 206 is buried. After that, patterning is performed to form the opening 208 (see FIG. 2C). In this example, the interlayer insulating film 207 is formed of a PSG film of 700 by atmospheric pressure CVD method.
It is deposited to a thickness of nm, but in addition to this, NSG film,
BPSG film, P-SiN film by P-CVD method, PS
The iO film, the P-SiON film, and the various insulating films described above can be compositely deposited in a thickness range of 100 to 1000 nm. Next, the first conductive film 2 is formed on the patterned interlayer insulating film 207 and the opening 208.
09 and the second conductive film 210 are continuously deposited (see FIG. 2D). Here, TaN having a thickness of 100 nm is deposited on the first conductive film 209 by a sputtering method, and this TaN is used as a heating resistor. The second conductive film 210 that follows is formed by sputtering Al.
The system material is deposited to a thickness of 550 nm. The step portion 2 is formed by the interlayer insulating film 207 and the second conductive film 210.
11 is formed.

Next, by patterning, at least a part of the second conductive film 210 is removed along the step portion 211. Continuing patterning is performed to remove the first conductive film 209 to form a plurality of individual heating resistors (see FIG. 2E). The opening portion 212 is formed by this patterning.

Next, an insulating film 213 is deposited on the opening 212 and the patterned first conductive film 209 and second conductive film 210. In this example, the P-SiN film is deposited to a thickness of 200 nm by the P-CVD method, but in addition to this, a P-SiO film, a P-SiON film, or the like may be deposited to a required film thickness. it can.

Subsequently, another insulating film 214 is deposited on the insulating film 213 (see FIG. 2F). The insulating film 214 is a PSG film formed by a normal pressure CVD method and has a thickness of 800 nm.
PSG membranes, and combinations of these membranes can be used.

Thereafter, the opening 2 is formed by patterning.
The insulating film 214 covering the inside of 12 is etched to form an opening 216. After that, the entire protective film 2
15 is deposited to form a hole 216, which serves as a heat generating portion (see FIG. 2G). Here, as the protective film 215, Ta is deposited to a thickness of 200 nm by a sputtering method.

In this embodiment, the electrothermal conversion element is formed as described above. Since the heat storage layer (insulating film 206) of the electrothermal conversion element is widely embedded in the semiconductor substrate 201 as described above, the heat transfer efficiency is significantly improved, and thus the heat storage / heat radiation cycle can be shortened. Further, since the thickness of the insulating film 213 (SiN film) on the heating resistor (first conductive film 209: TaN) is also thin, the heat conduction efficiency is improved also here, and the heat storage layer (insulating film) is improved. 206), it is possible to achieve a synergistically high efficiency of heat conduction.

Further, since the film thickness of the interlayer insulating film 207 can be made thin, it becomes possible to apply a thin layer of resist or the like at the time of patterning when forming metal wiring, and also to form fine metal wiring by high resolution. It will be possible. Furthermore,
Since the internal stress of the interlayer insulating film 207 itself is reduced, disconnection of the metal wiring due to stress migration can be suppressed, and highly reliable metal wiring can be formed.

Next, the manufacturing process of the electrothermal conversion driving element according to this embodiment will be described with reference to FIGS. P
Type silicon substrate 1 (impurity concentration 1 × 10 ¹² to 1 × 10 ¹⁶
After forming a 800 nm-thick thermal oxide film on the surface of (cm ⁻³ ), the thermal oxide film of the portion forming the N-type collector buried region 2 of each cell was removed by a photolithography process.

After forming the thermal oxide film, N-type impurities (for example, P, As, etc.) are ion-implanted, and the N-type collector buried region 2 having an impurity concentration of 1 × 10 ¹⁸ cm ^-3 or more is formed by thermal diffusion.
Was formed to a thickness of 2 to 6 μm, and the sheet resistance was set to a low resistance of 80 Ω / □ or less. Then, the thermal oxide film in the region where the P-type isolation buried region 3 is formed is removed to 100 nm.
After forming a thermal oxide film having a thickness, P-type impurities (for example, B
Etc.) is ion-implanted and the impurity concentration is 1 × 1 by thermal diffusion.
A P-type isolation buried region 3 having a size of 0 ¹⁵ to 1 × 10 ¹⁷ cm ⁻³ or more was formed.

Next, after removing the thermal oxide film on the entire surface, the N-type epitaxial region 4 (impurity concentration 1 × 10 ¹³ to 1 × 1) is formed.
0 ¹⁵ cm ⁻³ ) was epitaxially grown to a thickness of about 5 to 20 μm.

Next, a thermal oxide film with a thickness of about 100 nm is formed on the surface of the N-type epitaxial region 4, resist patterning is performed by a photolithography process, and P
P-type impurities were ion-implanted only in the portion forming the type isolation region 6. After removing the resist, the thermal diffusion should reach the P-type isolation buried region 3,
P-type isolation region 6 (impurity concentration 1 × 10 ¹⁸ to
1 × 10 ²⁰ cm ⁻³ ) was formed to a thickness of about 10 μm.

Next, patterning is performed by a photolithography process to remove the thermal oxide film only in the portion where the N-type collector region 7 is to be formed.
It is formed to have a thickness of about 35 nm, P ions are implanted, and thermal diffusion after that reaches the N ⁺ collector buried region 2 and the sheet resistance becomes a low resistance of 10 Ω / □ or less. Concentration 1 × 10 ¹⁸ to 1 × 10 ²⁰ cm
^-3 degree) formed. In this case, the collector region 7 has a thickness of about 10 μm.

Next, a SiN film is deposited to a thickness of about 200 nm by the LP-CVD method, a resist is applied, and patterning is performed to remove the SiN film in the region where the heat storage layer (insulating film) 206 is formed. Subsequently, the N-type epitaxial region 4 in the region where the heat storage layer (insulating film) 206 is formed is etched by the dry etching method. After removing the resist
Thermal oxidation is performed to deposit a thermal oxide film of 2 μm, a heat storage layer (insulating film) 206 is formed, and then the SiN film is removed.

Next, a thermal oxide film having a thickness of about 50 nm was formed, resist patterning was performed, and P-type impurities were ion-implanted only in the portion where the low-concentration P-type base region 5 was formed. After removing the resist, the low-concentration base region 5 (P-type base region, impurity concentration 1 × 10 ¹⁴ to 1 × 10 ^{4) is formed} by thermal diffusion.
^{About 17} cm ^-3 ) was formed to a thickness of about 5 to 10 μm. The P-type base region 5 is formed by forming the N ⁺ collector buried region 2 and the P-type isolation buried region 3 on the P-type silicon substrate 1, then removing the oxide film, and thereafter 5 × 10 ^{14 is formed.}
It is also possible to grow a low-concentration P-type epitaxial layer (not shown) of about 5 × 10 ¹⁷ cm ^{−3 by} about ³ to 10 μm.

Further, when the P-type epitaxial layer is used as described above, it is possible to make the structure in which the P-type isolation buried region 3 and the P-type isolation region 6 are unnecessary, and the P-type isolation buried region is used. The photolithography process for forming the buried region 3, the P-type isolation region 6, and the low-concentration base region 5, and the high temperature impurity diffusion process can be deleted or omitted.

Next, resist patterning was performed, and P-type impurities were implanted only in the portions where the high-concentration P-type base region 8 and the high-concentration P-type isolation region 9 were formed. After removing the resist, resist patterning is performed again, and N-type impurities are implanted to form the high-concentration N-type emitter region 10 and the high-concentration N-type collector region 11. After removing the resist, the high-concentration P-type base region 8, the high-concentration P-type isolation region 9, the high-concentration N-type emitter region 10 and the high-concentration N-type collector region 11 were simultaneously formed by thermal diffusion. In addition, these areas (8 ~
The thickness of 11) is 1.0 μm or less, and the impurity concentration is about 1 × 10 ¹⁸ to 1 × 10 ²⁰ cm ⁻³ .

Further, after removing the thermal oxide film at the connection part of the partial electrodes, Al or the like is deposited on the entire surface, and A except the partial electrode region is formed.
1 and the like were removed. Then, the interlayer film 2 is formed by the atmospheric pressure CVD method.
A PSG film of No. 07 was formed on the entire surface to a thickness of about 0.6 to 2.0 μm. SiO 2 by P-CVD method,
SiON or SiN films can also be used.

Next, the interlayer film 2 corresponding to the upper portions of the emitter region and the base / collector region for electrical connection.
A part of 07 is opened by patterning to form a through hole. Next, TaN as the heat generation resistance layer which is the first conductive film 209 is formed in order to establish electrical connection with the interlayer film 207, the emitter region, the emitter electrode 13 above the base / collector region, and the collector / base. Through a through hole on the common electrode 12 and a thickness of 100n
About m was deposited.

Next, the second conductive film 210 is deposited on the first conductive film 209. Here, as the second conductive film, a layer made of an Al material by a sputtering method was deposited to a thickness of about 500 nm. Subsequently, Al and TaN (first conductive film 20)
9) was patterned to simultaneously form the electrothermal conversion element and other wiring.

Next, the insulating film 213 is formed by the P-CVD method or the like.
Is deposited. In this example, the P-SiN film is formed to a thickness of 200 n.
It is deposited to a thickness of m. Further, the insulating film 214 is deposited by the atmospheric pressure CVD method or the like. In this example, the PSG film is
It is deposited to a thickness of 800 nm.

Next, by patterning, the insulating film 214 (PSG film) on the heat storage layer (insulating film) 206 is etched to form an opening. In this example, the insulating film 213 (P-SiN film) is exposed only on the bottom surface of the opening. Finally, as the protective film 215, Ta is formed to a thickness of 200 n.
About m was deposited. Here, the opening portion 216 operates as a heat generating portion.

FIG. 5 shows a comparison of changes in voltage when the electrothermal conversion driving element according to the present invention and a conventional product are incorporated in a recording head and ink is actually foamed. It can be seen that the ink foaming voltage is obviously reduced by about 30% in the sample according to the present invention.

[0057]

As described above, in the present invention, by embedding and forming the heat storage layer in the semiconductor substrate, the heat conduction efficiency for heat storage / heat dissipation can be greatly improved. Further, by reducing the thickness of the protective film of the heat generating portion, the heat conduction efficiency in the heat generating resistor can be significantly improved. Furthermore, by independently forming the heat storage layer and the interlayer insulating film, the interlayer insulating film can be thinned and fine through holes can be formed, so that fine metal wiring can be formed. Become.

Furthermore, since the interlayer insulating film can be thinned, the internal stress of the interlayer insulating film itself can be reduced, so that disconnection of the metal wiring due to stress migration can be prevented and a highly reliable metal can be obtained. The present invention has remarkable effects such as the possibility of forming wiring.

[Brief description of drawings]

FIG. 1 is an explanatory view of a process flow according to a schematic cross-sectional view of an electrothermal conversion element in Example 1.

FIG. 2 is a process flow explanatory diagram according to a schematic cross-sectional view of an electrothermal conversion element in Example 2.

FIG. 3 is a schematic cross-sectional view of a recording head substrate on which an electrothermal conversion element is formed according to the present invention.

FIG. 4 is a schematic cross-sectional view of an electrothermal conversion element formed by a conventional method.

FIG. 5 is a graph showing a comparison of ink bubbling voltage between the recording head according to the present invention and the recording head according to the conventional method. (However,
A shows the change of the ink bubbling voltage of the sample in which only the insulating film thickness on the heating portion of the electrothermal conversion element was changed based on the conventional example, and B shows the heat storage layer embedded in the semiconductor substrate according to the present invention, and FIG. 5 shows changes in the ink bubbling voltage of samples in which the insulating film thickness on the heat generating portion of the electrothermal conversion element was changed. )

[Explanation of symbols]

1 P-type silicon substrate 2 N ⁺ collector burying region 3 P-type isolation burying region 4 N-type epitaxial region 5 P-type base region 6 P-type isolation region 7 N-type collector region 8 High-concentration base region 9 High-concentration P Type isolation region 10 high concentration N type emitter region 11 high concentration N type collector region 12 collector base common electrode 13 emitter electrode 14 isolation electrode 101, 201 semiconductor substrate 102, 102a, 105, 111, 113, 202,
203, 206, 213, 214, 403, 304
Insulating film 103,204 Photosensitizer 104,107,109,112,114,116,2
05, 208, 212, 216, 407 Opening part 106, 207 Interlayer insulating film 108, 209 First conductive film 110, 210 Second conductive film 115, 215, 410, 411 Protective film 211 Step part 401 N-type epitaxial region 402 Driving element 405 First electrode 406 Heat storage layer 408 Heat generation resistance layer 409 Wiring electrode 412 Heat generating part

Claims (16)

[Claims] 1. A recording head substrate in which a plurality of electrothermal conversion elements are formed on an insulating film, and the electrothermal conversion driving elements for driving the electrothermal conversion elements are formed in a semiconductor substrate. A recording head substrate, wherein the substrate is embedded in the semiconductor substrate. 2. The recording head substrate according to claim 1, wherein the insulating film is embedded in an opening of the semiconductor substrate. 3. The recording head substrate according to claim 1, wherein the insulating film operates as a region for storing heat and radiating heat of the electrothermal conversion element. 4. The recording head substrate according to claim 3, comprising one or more of the insulating films. 5. The recording head substrate according to claim 1, wherein the electrothermal converting element is formed in an opening of an interlayer insulating film laminated on the semiconductor substrate. 6. The recording head substrate according to claim 5, wherein two types of insulating films are deposited on the electrothermal conversion element. 7. The recording head substrate according to claim 6, wherein the two types of insulating films have different thicknesses. 8. The recording head according to claim 6, wherein only one of the two types of insulating films deposited in the opening is removed to form the opening. Substrate. 9. A method of manufacturing a recording head substrate, comprising: forming a plurality of electrothermal conversion elements on an insulating film; and forming each electrothermal conversion driving element for driving each electrothermal conversion element in a semiconductor substrate. A method of manufacturing a recording head substrate, wherein the insulating film is embedded in the semiconductor substrate. 10. The method of manufacturing a recording head substrate according to claim 9, wherein the insulating film is embedded in an opening of the semiconductor substrate. 11. The method of manufacturing a recording head substrate according to claim 9, wherein the insulating film is operated as a region for storing heat and radiating heat of the electrothermal conversion element. 12. The method of manufacturing a recording head substrate according to claim 11, wherein the insulating film has one or more insulating films. 13. The method for manufacturing a recording head substrate according to claim 9, wherein the electrothermal conversion element is formed in an opening of an interlayer insulating film laminated on the semiconductor substrate. 14. The method of manufacturing a recording head substrate according to claim 13, wherein two types of insulating films are deposited on the electrothermal conversion element. 15. The method of manufacturing a recording head substrate according to claim 14, wherein the two types of insulating films have different thicknesses. 16. The recording head according to claim 14, wherein only one of the two types of insulating films deposited in the opening is removed to form the opening. Substrate manufacturing method.