KR101404094B1 - Pressure sensor and method of manufacturing the same - Google Patents

Abstract

The present invention provides a pressure sensor with a small size, excellent sensitivity and a simplified manufacturing process. According to an aspect of the present invention, there is provided a pressure sensor including: a substrate having a cavity formed therein; A pressure-receiving layer positioned on the substrate to seal the cavity, the pressure-receiving layer being deformed by external pressure; And a pressure sensing layer that protrudes from the substrate in the cavity and is located below the pressure receiving layer and senses the pressure as the electrical resistance value changes due to residual stress generated by the deformation of the pressure receiving layer.

Description

Technical Field The present invention relates to a pressure sensor and a manufacturing method thereof,

TECHNICAL FIELD The present invention relates to a pressure sensor, and more particularly, to a pressure sensor formed using a MEMS (MEMS) technology and a method of manufacturing the same.

The pressure sensor is a device that can measure atmospheric pressure and can accurately measure the altitude based on the pressure. Accordingly, the present invention can be applied to a precise location-based service in a building in which a GPS does not operate, and to a service requiring accurate pressure information such as TPMS.

A general structure of a pressure sensor capable of measuring absolute pressure consists of a membrane that is deformed by external pressure and a piezoelectric resistor, a cavity, and a substrate formed on the membrane. Conventional pressure sensors have been formed using bulk micromachining or surface micromachining.

In the case of a pressure sensor formed using a substrate processing technique, a process of etching the back surface of the sensor substrate and bonding other substrates to form a cavity is required. Therefore, there is a concern that the process becomes complicated due to the additional process, and the sensitivity of the sensor is reduced due to the residual stress caused by the bonding of the two substrates.

In the case of a pressure sensor formed using surface processing technology, polysilicon or silicon nitride is used as the membrane layer, and therefore, polysilicon or metal should be used as the piezoelectric resistor material. Therefore, there is a limit in that the sensitivity of the pressure sensor becomes very low due to the material of the piezoelectric resistor.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pressure sensor having a small size, a high sensitivity and a simplified manufacturing process.

Another technical problem to be solved by the technical idea of the present invention is to provide a method of manufacturing a pressure sensor in which a small size, excellent sensitivity and a manufacturing process are simplified.

According to an aspect of the present invention, there is provided a pressure sensor comprising: a substrate having a cavity formed therein; A pressure-receiving layer positioned on the substrate to seal the cavity, the pressure-receiving layer being deformed by external pressure; And a pressure sensing layer that protrudes from the substrate in the cavity and is located below the pressure receiving layer and senses the pressure as the electrical resistance value changes due to residual stress generated by the deformation of the pressure receiving layer.

In some embodiments of the present invention, the device may further include an etch stop layer located below the pressure sensing layer and isolating the pressure sensing layer from the cavity.

In some embodiments of the present invention, a separation layer may be further disposed between the pressure sensing layer and the etch stop layer.

In some embodiments of the present invention, the pressure sensing layer and the etch stop layer may comprise a first impurity having a first conductivity type. In addition, the isolation layer may include a second impurity having a second conductivity type different from the first conductivity type.

In some embodiments of the present invention, the first conductivity type may be a p-type conductivity type and the second conductivity type may be an n-type conductivity type.

In some embodiments of the present invention, the pressure sensing layer may contain impurities at a lower concentration than the etch stop layer.

In some embodiments of the present invention, it may further comprise a mask layer isolating the pressure sensing layer from the cavity.

In some embodiments of the present invention, the pressure receiving layer may comprise silicon oxide, silicon nitride, silicon oxynitride or polysilicon. In addition, the pressure sensing layer may include monocrystalline silicon.

In some embodiments of the present invention, the apparatus may further include a boundary member located at an outer periphery of the cavity and defining a size of the pressure receiving layer.

According to an aspect of the present invention, there is provided a method of manufacturing a pressure sensor comprising: forming a boundary member surrounding a part of a substrate; Removing a portion of the substrate to form a recessed region; Forming a sacrificial layer filling the recessed region; Forming an etch stop layer, a separation layer, and a pressure sensing layer, wherein the etch stop layer, the isolation layer, and the pressure sensing layer are disposed between the boundary member and the sacrificial layer and doped with impurities in a protruding region of the substrate defined by the recessed region; Removing the sacrificial layer and a lower portion of the substrate to form a cavity; And forming a pressure-receiving layer on the cavity to seal the cavity.

The pressure sensor according to the technical idea of the present invention is a device capable of measuring the absolute pressure, and since the pressure sensor can be manufactured by simultaneously applying the surface micromachining and the front-side bulk micromachining , The pressure-receiving layer is made of silicon oxide, silicon nitride or polysilicon, while the pressure-sensitive layer can be made of monocrystalline silicon having a high piezoelectric coefficient, and a built-in vacuum cavity can be formed. Therefore, the sensitivity of the pressure sensor is high, the size of the device can be reduced, and the manufacturing process is simplified.

Also, unlike the prior art in which cavities are formed by joining substrates, cavities are formed by filling vacancies with an insulating material and then removing the cavities by etching, thereby preventing the occurrence of residual stresses, The reduction loss of the sensor can be prevented.

In addition, since the cavity is formed by the vertical etching method by reactive ion etching, the loss of the area required for the pressure sensor can be minimized.

The effects of the present invention described above are exemplarily described, and the scope of the present invention is not limited by these effects.

1 is an external perspective view showing a pressure sensor according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view of the pressure sensor of FIG. 1 according to an embodiment of the present invention.
3 is a cross-sectional view of the pressure sensor of FIG. 2 taken along lines AA and BB, according to an embodiment of the present invention.
4 to 17 are sectional views schematically showing a method of manufacturing the pressure sensor of FIG. 2 according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. The scope of technical thought is not limited to the following examples. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the scope of the invention to those skilled in the art. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items. The same reference numerals denote the same elements at all times. Further, various elements and regions in the drawings are schematically drawn. Accordingly, the technical spirit of the present invention is not limited by the relative size or spacing depicted in the accompanying drawings.

1 is an external perspective view showing a pressure sensor 100 according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing the pressure sensor 100 of FIG. 1 according to an embodiment of the present invention. 3 is a cross-sectional view taken along line A-A and B-B of the pressure sensor 100 of FIG. 2 according to an embodiment of the present invention.

Referring to FIG. 1, a pressure sensor 100 includes a substrate 110 and a pressure receiving layer 150 disposed on the substrate 110. Optionally, a first mask layer 130 may be further positioned between the substrate 110 and the pressure receiving layer 150.

2 and 3, the pressure sensor 100 includes a substrate 110, a pressure-receiving layer 150, and a pressure-sensitive layer 146. In addition, the pressure sensor 100 may include a boundary member 120.

The substrate 110 may comprise a semiconductor material and may include, for example, silicon, germanium, or silicon-germanium. The substrate 110 may be a single crystal material, for example, monocrystalline silicon. The substrate 110 may include a cavity 160. Cavity 160 may be a vacuum.

The pressure receiving layer 150 may be positioned to seal the cavity 160 on the substrate 110. The pressure receiving layer 150 may include a material that is deformed by external pressure. For example, the pressure-receptive layer 150 may comprise an insulating material and may include, for example, an oxide, nitride, or oxynitride and may include, for example, silicon oxide, silicon nitride, Or the pressure receiving layer 150 may include undoped polysilicon. The pressure receiving layer 150 may be comprised of a third mask layer 152 and a cover layer 154 and may further include an extension 156 extending to define the cavity 160. The pressure receiving layer 150 may be referred to in the art as a membrane.

The pressure sensing layer 146 may be located in the cavity 160 and may protrude laterally from the substrate 110 and be positioned below the pressure receiving layer 150. The pressure sensing layer 146 can sense the absolute pressure as the electrical resistance value changes due to the piezoelectric effect due to the residual stress generated by the external pressure of the pressure receiving layer 150. The pressure sensing layer 146 may comprise a monocrystalline material and may include, for example, monocrystalline silicon. On the other hand, the pressure receiving layer 150 may include silicon oxide, silicon nitride, polysilicon, or the like.

The pressure sensing layer 146 may be formed by doping the substrate 110 with a first conductive impurity. The first conductive impurity contained in the pressure sensing layer 146 may include a p-type conductive material, for example, a Group III element. The pressure sensing layer 146 may include, for example, boron (B), aluminum (Al), gallium (Ga), indium (In) The pressure sensing layer 146 is deformed by the external pressure and the electrical resistance value may be changed due to the piezoelectric effect due to the residual stress generated by the deformation of the pressure receiving layer 150, Whereby the external pressure can be measured.

The pressure sensing layer 146 may be included in the doping layer 140. For example, the doping layer 140 may include a pressure sensitive layer 146, an isolation layer 144, and an etch stop layer 142.

The etch stop layer 142 may be located below the pressure sensing layer 146. The etch stop layer 142 is located below the pressure sensing layer 146 and isolates the pressure sensing layer 146 from the cavity 160. The etch stop layer 142 may function to prevent etching by blocking the pressure sensing layer 146 from the etchant in the etching processes for forming the cavity 160. The etch stop layer 142 may be formed by doping the first conductive impurity into the substrate 110. The first conductive impurity contained in the etch stop layer 142 may include a p-type conductive material, for example, a Group III element. The etch stop layer 142 may include, for example, boron (B), aluminum (Al), gallium (Ga), indium (In) The etch stop layer 142 may be formed by doping the first conductive type impurity with a relatively high energy, and thus the first conductive type impurity may be contained at a relatively high concentration. On the other hand, the pressure sensing layer 146 may be formed by doping the first conductive impurity with a relatively low energy, and thus may include the first conductive impurity at a relatively low concentration.

A separation layer 144 may be positioned between the pressure sensing layer 146 and the etch stop layer 142. The separation layer 144 is interposed between the etch stop layer 142 and the pressure sensing layer 146 and may function to physically separate the etch stop layer 142 and the pressure sensing layer 146. The isolation layer 144 may be formed by doping the substrate 110 with a second conductivity type impurity having a conductivity type different from that of the first conductivity type impurity. The second conductive impurity contained in the isolation layer 144 may include an n-type conductive material and may include, for example, a Group V element. The isolation layer 144 may include, for example, nitrogen (N), phosphorous (P), arsenic (As), or antimony (Sb)

The above-described conductive types for the etching stop layer 142, the separation layer 144, and the pressure sensing layer 146 are illustrative, and the technical idea of the present invention is not limited thereto. For example, the case where the etching stop layer 142 and the pressure sensing layer 146 include an n-type conductivity type impurity and the separation layer 144 has a p-type conductivity type is also included in the technical idea of the present invention do.

The first mask layer 130 may be disposed on the pressure sensing layer 146 and the second mask layer 132 may be disposed on the side walls. The first mask layer 130 and the second mask layer 132 may be connected to each other. The first mask layer 130 and the second mask layer 132 may isolate the pressure sensing layer 146 from the cavity 160 so that in the etching processes for forming the cavity 160, It is possible to perform the function of preventing the etching from being blocked by the etching agent. The first mask layer 130 and the second mask layer 132 may be composed of a hard mask layer and may include a silicon material. In addition, the first mask layer 130 and the second mask layer 132 may include the same material or may include different materials.

The boundary member 120 is located at the outer periphery of the cavity 160 and can define the size of the pressure receiving layer 150. The pressure can be measured corresponding to the area of the pressure-receptive layer 150 surrounded by the boundary member 120. The boundary member 120 may prevent the pressure sensitive layer 146 from contacting the etchant in the etching process performed in manufacturing the pressure sensor 100 to prevent undesired etching of the pressure sensitive layer 146.

The boundary member 120 may have a polygonal shape, a garden shape, an elliptical shape, or the like, and may have a rectangular shape, for example. The boundary member 120 may extend from the lower side of the substrate 110 in the cavity 160 along the side wall of the cavity 160 and may also be interposed between the pressure sensing layer 146 and the substrate 110 Can be extended. The boundary member 120 may comprise an oxide, nitride, or oxynitride and may include, for example, silicon oxide, silicon nitride, or silicon oxynitride.

FIGS. 4 to 17 are cross-sectional views schematically showing a method of manufacturing the pressure sensor 100 of FIG. 2 according to an embodiment of the present invention. Figs. 4 to 17 respectively show cross-sections taken along line A-A and line B-B in Fig. 2, respectively. The sequence of the manufacturing process steps described with reference to Figs. 4 to 17 is illustrative, and the case of being performed in a different order is also included in the technical idea of the present invention.

Referring to FIG. 4, a substrate 110 is prepared. The substrate 110 may comprise a semiconductor material and may include, for example, silicon, germanium, or silicon-germanium. The substrate 110 may be a single crystal material, for example, monocrystalline silicon.

Referring to FIG. 5, a portion of the substrate 110 is removed to form a peripheral groove 112. The perimeter groove 112 may surround a predetermined area of the substrate 110 to define the area where the pressure sensor is formed, that is, the area of the pressure receiving layer 150. The removal process may be performed using dry etching.

Referring to FIG. 6, the peripheral groove 112 is filled with an insulating material to form a boundary member 120 surrounding a predetermined region of the substrate 110. The boundary member 120 may comprise an oxide, nitride, or oxynitride and may include, for example, silicon oxide, silicon nitride, or silicon oxynitride. The boundary member 120 may be formed to surround a region where the pressure sensor is formed. The boundary member 120 may be formed using thermal oxidation, sputtering, chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), or atomic layer deposition (ALD) .

Referring to FIG. 7, a first mask layer 130 is formed on a substrate 110. The first mask layer 130 may expose a portion of the substrate 110. The first mask layer 130 may be formed to expose the boundary member 120 in the A-A cross section. On the other hand, the first mask layer 130 may be formed to cover the boundary member 120 in the B-B cross section. That is, the boundary member 120 is exposed from the first mask layer 130 at a corner, and covered by the first mask layer 130 in a region except a corner. The first mask layer 130 may be comprised of a hard mask layer and may comprise a silicon material. A photoresist mask (not shown) may be used to form the first mask layer 130.

Referring to FIG. 8, the substrate 110 exposed from the first mask layer 130 is removed to form a first recess region 131. The removal process may be an etching process, a wet etching process, a dry etching process, or an etch-back process, and reactive ion etching (RIE) may be used. The boundary member 120 may be removed from the exposed region (A-A cross-section) from the first mask layer 130 and not removed from the region covered by the first mask layer 130 (B-B cross-section).

Referring to FIG. 9, a second mask layer 132 extending from the first mask layer 130 is formed in the first recess region 131. The second mask layer 132 may expose a portion of the substrate 110. The second mask layer 132 may cover a portion of the bottom wall and the bottom wall in the first recess region 131. The second mask layer 132 may cover a part of the side wall and the bottom in the first recess region 131 in the A-A cross section and may be formed to cover the boundary member 120 as well. On the other hand, the second mask layer 132 may be formed so as to cover the side wall in the first recess region 131 in the B-B cross section. Note that, in the B-B cross section, the boundary member 120 is covered by the first mask layer 130. The second mask layer 132 may be comprised of a hard mask layer and may comprise a silicon material. A photoresist mask (not shown) may be used to form the second mask layer 132. Also, the first mask layer 130 and the second mask layer 132 may comprise the same material. The first mask layer 130 and the second mask layer 132 may be formed using sputtering, chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), atomic layer deposition (ALD), or the like.

Referring to FIG. 10, the substrate 110 exposed from the second mask layer 132 is removed to form a second recess region 133 extending from the first recess region 131. The removal process may be an etching process, a wet etching process, a dry etching process, or an etch-back process, and reactive ion etching (RIE) may be used. The second recess region 133 may be formed so as to have a step in the A-A cross section and not in the B-B cross section. In addition, the substrate 110 can be exposed by the second recessed region 133. The depth of the second recessed region 133 is preferably smaller than the depth of the boundary member 120.

Referring to Fig. 11, a sacrifice layer 135 for filling the second recess region 133 is formed. The sacrifice layer 135 may be formed by filling the second recess region 133 with an insulating material and then planarizing using etch-back or chemical mechanical polishing (CMP). The top surface of the sacrificial layer 135 may be coplanar with the top surface of the first mask layer 130. The sacrificial layer 135 may comprise, for example, an oxide, a nitride, or an oxynitride, and may include, for example, silicon oxide, silicon nitride, or silicon oxynitride. In addition, the sacrificial layer 135 may include a material having an etch selectivity different from that of the first mask layer 130 and the second mask layer 132. The sacrificial layer 135 may be formed using sputtering, chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), atomic layer deposition (ALD), or the like.

Referring to FIG. 12, a plurality of doped layers 140 are formed by doping impurities in a protruding region of the substrate 110 located between the boundary member 120 and the second mask layer 132. The plurality of doped layers 140 may be formed using diffusion and / or ion implantation. The doping layers 140 may include an etch stop layer 142, a separation layer 144, and a pressure sensing layer 146. The etch stop layer 142 is located at the bottom of the doping layer 140 and the isolation layer 144 is located on the etch stop layer 142 and the pressure sensing layer 146 may be located on the isolation layer 144. have.

The etch stop layer 142 may be formed by doping a first conductive impurity into a protruding region of the substrate 110. The first conductive impurity contained in the etch stop layer 142 may include a p-type conductive material, for example, a Group III element. The etch stop layer 142 may include, for example, boron (B), aluminum (Al), gallium (Ga), indium (In) The etch stop layer 142 may be formed by doping the first conductive type impurity with a relatively high energy, and thus the first conductive type impurity may be contained at a relatively high concentration. The etch stop layer 142 may function to prevent etching by blocking the pressure sensing layer 146 from the etchant in subsequent etching processes for forming the cavity 160. The etch stop layer 142 may be located between the boundary member 120 and the second mask layer 132 and may extend to the lower end of the second mask layer 132 as well.

The isolation layer 144 may be formed by doping a second conductive impurity having a conductivity type different from that of the first conductive impurity into a protruding region of the substrate 110. The second conductive impurity contained in the isolation layer 144 may include an n-type conductive material and may include, for example, a Group V element. The isolation layer 144 may include, for example, nitrogen (N), phosphorous (P), arsenic (As), or antimony (Sb) The isolation layer 144 may be located above the etch stop layer 142 and below the pressure sensing layer 146. The isolation layer 144 is interposed between the etch stop layer 142 and the pressure sensing layer 146 and may function to physically separate the etch stop layer 142 and the pressure sensing layer 146 .

The pressure sensitive layer 146 may be located on the isolation layer 144 and may also be surrounded by the isolation layer 144. The upper side of the pressure sensing layer 146 may be covered by the first mask layer 130. One side wall of the pressure sensing layer 146 may be covered by the second mask layer 132 and the other side wall of the pressure sensing layer 146 may be covered by the separation layer 144. The pressure sensing layer 146 may be formed by doping the first conductive impurity into the protruding region of the substrate 110. In particular, the pressure sensing layer 146 may be formed on the substrate 110 by doping the first conductive impurity. The first conductive impurity contained in the pressure sensing layer 146 may include a p-type conductive material, for example, a Group III element. The pressure sensing layer 146 may include, for example, boron (B), aluminum (Al), gallium (Ga), indium (In) The pressure sensing layer 146 may be formed by doping the first conductive impurity with a relatively low energy, thereby allowing the first conductive impurity to be contained at a relatively low concentration. The pressure sensing layer 146 is deformed by the external pressure and the pressure receiving layer 150 (see FIG. 3) is deformed and the residual stress caused by the deformation of the pressure receiving layer 150 The resistance value can be changed, and thus the external pressure can be measured.

As described above, after impurities are doped to form the etch stop layer 142, the separation layer 144, and the pressure sensing layer 146, the impurities can be activated through an appropriate heat treatment process.

The above-described conductive types for the etching stop layer 142, the separation layer 144, and the pressure sensing layer 146 are illustrative, and the technical idea of the present invention is not limited thereto. For example, the case where the etching stop layer 142 and the pressure sensing layer 146 include an n-type conductivity type impurity and the separation layer 144 has a p-type conductivity type is also included in the technical idea of the present invention do.

Since the etching stop layer 142, the separation layer 144 and the pressure sensing layer 146 are formed from the substrate 110, when the substrate 110 is a single crystal material, the etching stop layer 142, the separation layer 144 ), And the pressure sensing layer 146 may each be a single crystal material.

Referring to FIG. 13, a third mask layer 152 is formed on a substrate 110. The third mask layer 152 may extend to cover the sacrificial layer 135 and the first mask layer 130. The third mask layer 152 may comprise an insulating material, for example, an oxide, a nitride, or an oxynitride, and may include, for example, silicon oxide, silicon nitride, or silicon oxynitride. Alternatively, the third mask layer 152 may comprise undoped polysilicon.

Referring to FIG. 14, a portion of the third mask layer 152 is removed to form an etch opening 153 exposing the sacrificial layer 135. The etching openings 153 may be formed on the outside of the boundary member 120, for example, and may be formed in plural.

Referring to FIG. 15, the first etching agent is injected through the etching opening 153 to remove the sacrificial layer 135. This removal process can be implemented using wet etching. A cavity 160 may be formed in the region where the sacrificial layer 135 is removed. When the sacrifice layer 135 is composed of an insulating material, the first etchant may include hydrochloric acid, hydrofluoric acid, hydrogen peroxide, and the like. The substrate 110 and the second mask layer 132 may be exposed in the cavity 160 as the sacrificial layer 135 is removed.

Referring to FIG. 16, a second etchant is injected through the etch opening 153 to remove a lower portion of the substrate 110. Accordingly, the size of the cavity 160 can be larger. When the substrate 110 is made of silicon, the second etchant may include a material capable of removing the silicon, for example, TMAH (Tetramethylammonium hydroxide), KOH, and the like. In the etching process, the boundary member 120, the first mask layer 130, the second mask layer 132, and the third mask layer 152 are etched by the second etchant Since the ratio is small, it can remain almost etched. In addition, the etch stop layer 142 may be substantially etched by the second etchant. The isolation layer 144 and the pressure sensing layer 146 are not surrounded by the etch stop layer 142 and the second mask layer 132 and do not contact the second etchant, Can be protected from etching.

Referring to FIG. 17, a cover layer 154 is formed on the third mask layer 152. The cover layer 154 may include an extension 156 to fill the etch opening 153. The extension 156 may extend to contact the second mask layer 132. The cover layer 154 may comprise an insulating material, for example, an oxide, a nitride, or an oxynitride, and may include, for example, silicon oxide, silicon nitride, or silicon oxynitride. Alternatively, the cover layer 154 may comprise undoped polysilicon. The cover layer 154 can be formed using sputtering, chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), atomic layer deposition (ALD), or the like. The third mask layer 152 and the cover layer 154 may comprise the same material.

The third mask layer 152 and the cover layer 154 together can constitute the pressure receiving layer 150. A cavity 160 may be formed on the lower side of the pressure receiving layer 150 and a cavity 160 may be formed on the pressure receiving layer 150. Inside the cavity 160, a pressure sensing layer 146 may be positioned in contact with the pressure receiving layer 150. The cover layer 154 can be formed in a vacuum atmosphere, so that the cavity 160 can have a vacuum. The pressure sensor 100 is completed through the above-described manufacturing process.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. Will be apparent to those of ordinary skill in the art.

100: pressure sensor, 110: substrate, 112: peripheral groove, 120:
130: first mask layer, 131: first recess region, 132: second mask layer,
133: second recess region, 135: sacrificial layer, 140: doped layer, 142: etch stop layer,
144: separation layer, 146: pressure sensing layer, 150: pressure receiving layer, 152: third mask layer,
153: etch opening, 154: cover layer, 156: extension, 160: cavity

Claims (11)

A substrate on which a cavity is formed;
A pressure-receiving layer positioned on the substrate to seal the cavity, the pressure-receiving layer being deformed by external pressure; And
A pressure sensing layer that protrudes from the substrate in the cavity and is positioned below the pressure receiving layer and senses a pressure as the electrical resistance value changes due to a residual stress caused by the deformation of the pressure receiving layer;
/ RTI >
Wherein the pressure receiving layer comprises silicon oxide, silicon nitride, silicon oxynitride or polysilicon,
Wherein the pressure sensing layer comprises monocrystalline silicon. The method according to claim 1,
An etch stop layer located below the pressure sensing layer and isolating the pressure sensing layer from the cavity;
Further comprising a pressure sensor. 3. The method of claim 2,
A separation layer positioned between the pressure sensing layer and the etch stop layer;
Further comprising a pressure sensor. The method of claim 3,
Wherein the pressure sensing layer and the etch stop layer comprise a first impurity having a first conductivity type,
Wherein the isolation layer includes a second impurity having a second conductivity type different from the first conductivity type. 5. The method of claim 4,
The first conductivity type is a p-type conductivity type,
And the second conductivity type is an n-type conductivity type. 3. The method of claim 2,
Wherein the pressure sensing layer contains impurities at a lower concentration than the etch stop layer. The method according to claim 1,
A mask layer isolating the pressure sensing layer from the cavity;
Further comprising a pressure sensor. delete The method according to claim 1,
A boundary member located at an outer periphery of the cavity and defining a size of the pressure receiving layer;
Further comprising a pressure sensor. Forming a boundary member surrounding a portion of the substrate;
Removing a portion of the substrate to form a recessed region;
Forming a sacrificial layer filling the recessed region;
Forming an etch stop layer, a separation layer, and a pressure sensing layer, wherein the etch stop layer, the isolation layer, and the pressure sensing layer are disposed between the boundary member and the sacrificial layer and doped with impurities in a protruding region of the substrate defined by the recessed region;
Removing the sacrificial layer and a lower portion of the substrate to form a cavity; And
Forming a pressure-receiving layer on the cavity to seal the cavity;
Wherein the pressure sensor comprises a pressure sensor. A pressure sensor manufactured by the method of manufacturing a pressure sensor according to claim 10,
The pressure sensor includes:
A substrate on which a cavity is formed;
A pressure-receiving layer positioned on the substrate to seal the cavity, the pressure-receiving layer being deformed by external pressure; And
A pressure sensing layer that protrudes from the substrate in the cavity and is positioned below the pressure receiving layer and senses a pressure as the electrical resistance value changes due to a residual stress caused by the deformation of the pressure receiving layer;
.

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