JP2019007760A - Through electrode substrate, through electrode substrate manufacturing method and dynamic quantity sensor - Google Patents

Abstract

To provide a high airtight through electrode substrate.SOLUTION: A through electrode substrate includes: a substrate 110 having a first surface 110A, a second surface 110B on a reverse side of the first surface 110A, and a through hole 115; a through electrode 120 filled in the through hole 115; a side surface 120E of the through electrode 120; a slit 125 arranged with a side wall 115A of the through hole 115; a first inorganic material 130 covering an end portion 120C of the through electrode 120 and the slit 125 on a side of the first surface 110A of the substrate 110, contacting to a portion of an upper surface 120A of the through electrode 120 and the first surface 110A of the substrate 110, and having a first opening portion 135 on the trough electrode 120; and a second inorganic material 150 covering an end portion 120D of the trough electrode 120 and the slit 125 on a side of the second surface 110B of the substrate 110, contacting to a part of a lower surface 120B of the through electrode 120 and the second surface 110B of the substrate 110, and having a second opening portion 155 on the through electrode 120.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a through electrode substrate, a method for manufacturing the through electrode substrate, and a mechanical quantity sensor.

  Some electronic devices require a structure that completely shuts off the outside air (medium airtight structure), and the structure that completely shuts off the outside air is called a hermetic seal. For example, in order to protect electronic components from environmental conditions such as moisture, dust, and heat in the air, it is necessary to have an airtight structure. Furthermore, an electrode terminal is required to take out an output signal as a result of power supply or some sensing of the airtight electronic component. As the above-mentioned electronic component, in particular, a mechanical quantity sensor that detects an absolute value of an external force (hydraulic pressure, atmospheric pressure, vacuum degree) that changes from moment to moment is widely used in many industrial fields to precisely control the device. ing. For example, as a mechanical quantity sensor using a diaphragm, a small mechanical quantity sensor has been developed. Patent Document 1 discloses a technique for measuring a pressure from a capacitance value generated between a diaphragm and a detection electrode provided opposite to the diaphragm. In the above technique, a through electrode substrate is used as the detection electrode.

JP 2009-258088 A

  In the mechanical quantity sensor, the pressure inside the sensor needs to be constant. That is, the inside of the mechanical quantity sensor needs to have high airtightness. However, depending on the shape of the through electrode or the manufacturing method, the airtightness between the through electrode and the substrate in the through electrode substrate is not sufficient, and the mechanical quantity sensor may not normally function. Examples of the mechanical quantity sensor include an acceleration sensor, an angular velocity sensor (gyro, yaw rate), a pressure sensor, an odor sensor, a CMOS / CCD image sensor, and the like, all of which require high airtightness.

  In view of such a problem, an object of the embodiment of the present disclosure is to provide a through-electrode substrate having high airtightness.

  According to an embodiment of the present disclosure, the first surface, the second surface opposite to the first surface, and the substrate including the through hole, the through electrode filled in the through hole, the side surface of the through electrode, and the through hole The slit disposed between the side wall and the first surface side of the substrate covers the end of the through electrode and the slit, is in contact with a part of the upper surface of the through electrode and the first surface of the substrate, and is formed on the through electrode. On the second surface side of the substrate, the first inorganic material having one opening portion covers the end of the through electrode and the slit, contacts a part of the upper surface of the through electrode and the second surface of the substrate, and on the through electrode A through electrode substrate is provided that includes a second inorganic material having a second aperture.

  In the through electrode substrate, the inorganic material is in contact with the side wall of the through hole.

  In the through electrode substrate, the upper surface of the through electrode has a dish-like concave shape.

  According to one embodiment of the present disclosure, the first surface, the second surface opposite to the first surface, and the substrate provided with the through hole, and the first surface, the second surface, and the side wall of the through hole of the substrate are provided. The underlayer, the through electrode provided on the underlayer, and the first surface side of the substrate cover the boundary portion and the through hole between the through electrode and the underlayer, and are in contact with the upper surface of the through electrode and the first surface of the substrate. And a first inorganic material having an opening on the through electrode.

  In the above through electrode substrate, the diameter of the through hole is 1 to 4 times the thickness of the first inorganic material.

  In the through electrode substrate, the first inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order, and the thickness of the second inorganic film is equal to that of the first inorganic film. The thickness is 1 to 30 times the thickness.

  In the through electrode substrate, the first inorganic film is a silicon nitride film, and the second inorganic film is a silicon oxide film.

  In the through electrode substrate, the first inorganic material is a sintered body.

  The through electrode substrate further includes a filler provided in the through hole and in contact with the through electrode on the side surface.

  The through electrode substrate further includes a conductive layer in contact with the first surface of the substrate, the upper surface of the through electrode on the first surface side, and the first inorganic material.

  According to one embodiment of the present disclosure, a base layer is formed on the first surface of the substrate, the second surface opposite to the first surface, and the side wall of the through hole, and the through electrode is formed so as to be in contact with the base layer. On the first surface side of the substrate, an inorganic material is formed so as to cover the boundary between the through electrode and the base layer and the through hole, and to be in contact with the top surface of the through electrode and the base layer. A method for manufacturing a through electrode substrate is provided, including forming a hole.

  In the method for manufacturing the through electrode substrate, the diameter of the through hole is 1 to 4 times the thickness of the inorganic material.

  In the method for manufacturing the through electrode substrate, the inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order, and the thickness of the second inorganic film is the first inorganic film. It is characterized in that it is 1 to 30 times the thickness.

  In the method for manufacturing the through electrode substrate, the first inorganic film made of an inorganic material is a silicon nitride film, and the second inorganic film made of an inorganic material is a silicon oxide film.

  In the method for manufacturing the through electrode substrate, the inorganic material is formed by a plasma CVD method.

  The method for manufacturing a through electrode substrate includes forming a filler so as to be in contact with a side surface of the through electrode.

  The method for manufacturing a through electrode substrate includes forming a filler so as to be in contact with a side surface of the through electrode in the through hole.

  In the method for manufacturing the through electrode substrate, the base layer is formed by an immersion method.

  According to one embodiment of the present disclosure, a mechanical quantity sensor including the through electrode substrate is provided.

  According to one embodiment of the present disclosure, it is possible to provide a through electrode substrate having a highly airtight through electrode.

It is sectional drawing explaining the mechanical quantity sensor which concerns on one Embodiment of this indication. It is a top view and a sectional view explaining a penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is a top view and a sectional view explaining a penetration electrode substrate concerning one embodiment of this indication. It is a top view and a sectional view explaining a penetration electrode substrate concerning one embodiment of this indication. It is a sectional view explaining a penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is sectional drawing explaining the manufacturing method of the penetration electrode substrate concerning one embodiment of this indication. It is a sectional view explaining a penetration electrode substrate concerning one embodiment of this indication.

  Hereinafter, a through electrode substrate, a mechanical quantity sensor, and the like according to each embodiment of the present disclosure will be described in detail with reference to the drawings. In addition, each embodiment shown below is an example of embodiment of this indication, Comprising: This indication is limited to these embodiment and is not interpreted. Note that in the drawings referred to in the present embodiment, the same portions or portions having similar functions are denoted by the same reference symbols or similar reference symbols (symbols having only xxx-1, xxx-2, etc.). The repeated description may be omitted. In addition, the dimensional ratio in the drawing may be different from the actual ratio for convenience of explanation, or a part of the configuration may be omitted from the drawing.

  Note that in this specification, terms such as “above” and “below” are used for convenience in describing the positional relationship between components with reference to the drawings. Moreover, the positional relationship between components changes suitably according to the direction which draws each structure. Therefore, the present invention is not limited to the words and phrases described in the specification, and can be appropriately rephrased depending on the situation.

<First Embodiment>
(1-1. Configuration of mechanical quantity sensor)
FIG. 1 shows a cross-sectional view of the mechanical quantity sensor 10. As shown in FIG. 1, the mechanical quantity sensor 10 includes a through electrode substrate 100, a substrate 210, an insulating layer 220, a conductive layer 230, and a thin film 235.

A silicon substrate is used as the substrate 210. For the insulating layer 220, silicon oxide, silicon nitride, hafnium oxide, aluminum oxide, or the like is used. A semiconductor material is used for the conductive layer 230, but a metal material or the like may be used. For example, when silicon (Si) is used for the conductive layer 230, a large amount of boron (B), aluminum (Al), phosphorus (P), arsenic (As), or the like is contained in the silicon (for example, 10 ¹⁸ to 10 ²⁰ atoms / cm). by about ³⁾ may include, it may have a conductivity. The substrate 210 and the insulating layer 220 have an opening 215.

  The thin film 235 is provided as a portion corresponding to the region 250 of the conductive layer 230. The film thickness of the thin film 235 may be set as appropriate, and is preferably 1 μm or more and 100 μm or less. The thin film 235 has flexibility. The thin film 235 has conductivity at least on the first surface 235A (upper surface).

  The mechanical quantity sensor 10 has a closed space 300, and the shape of the thin film 235 changes according to an external force (for example, pressure). For example, when the external force is large, the thin film 235 is greatly bent downward (on the first surface 235A side). Further, when the external force is small, the thin film 235 is less bent downward (on the first surface 235A side). Due to the difference in the shape change of the thin film 235, the distance between the thin film 235 and the electrode 140 provided on the through electrode substrate 100 changes. Thereby, since the electrostatic capacitance between the thin film 235 and the electrode 140 changes, this is regarded as an electric signal, and an electric signal corresponding to an external force is obtained. The configuration of the through electrode substrate 100 will be described in detail below.

(1-2. Configuration of the through electrode substrate)
2A is a top view between A1 and A2 of the through electrode substrate 100, and FIG. 2B is a cross-sectional view between A1 and A2 of the through electrode substrate 100. FIG. As shown in FIG. 2B, the through electrode substrate 100 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130, an electrode 140, an inorganic material 150, and an electrode 160.

  The substrate 110 has a first surface 110A and a second surface 110B opposite to the first surface 110A. The substrate 110 is provided with a through hole 115. As shown in FIG. 2B, the through hole 115 when viewed from above may have a circular shape. The diameter of the through hole 115 may be set as appropriate, but is preferably set in the range of 10 μm to 100 μm.

  A high resistance material is used for the substrate 110. For example, a glass substrate such as a quartz glass substrate, a soda glass substrate, a borosilicate glass substrate, or an alkali-free glass substrate is used as the substrate 110. The thickness of the substrate 110 may be set as appropriate, and is preferably set in the range of 200 μm to 700 μm.

Note that the substrate 110 is not limited to a glass substrate, and is a sapphire substrate, a silicon substrate, a silicon carbide substrate, an alumina (Al ₂ O ₃ ) substrate, an aluminum nitride (AlN) substrate, a zirconia (ZrO ₂ ) substrate, acrylic, polycarbonate, or the like. Alternatively, a resin substrate including the above or a laminate of these substrates may be used.

  The through electrode 120 is filled in the through hole 115. A low resistance material is used for the through electrode 120. For example, copper (Cu) is used for the through electrode 120. Note that the present invention is not limited to this, and a material containing gold (Au), silver (Ag), nickel (Ni), or tin (Sn) may be used.

  A slit 125 is provided between the side surface 120 </ b> E of the through electrode 120 and the side wall 115 </ b> A of the through hole 115. In the slit 125, gas generated during the formation of the through electrode substrate may stay.

  The inorganic material 130 is provided in contact with a part of the first surface 110 </ b> A of the substrate 110 and the upper surface 120 </ b> A of the through electrode 120. At this time, the inorganic material 130 covers the end portion 120 </ b> C and the slit 125 of the through electrode 120 as shown in FIGS. 2A and 2B. Thereby, movement of fluids, such as gas which exists between penetration electrode 120 and substrate 110, can be controlled.

  The inorganic material 130 may be in contact with the side wall 115A of the through hole 115 (that is, the inorganic material 130 may be provided in the slit 125). Thereby, the stress dispersion | distribution in 120 C of edge parts of the penetration electrode 120 can be aimed at more. In addition, the inorganic material 130 has an opening 135 in the upper surface 120 </ b> A of the through electrode 120.

  Further, the side surface 130A of the inorganic material 130 may have a tapered shape. Thereby, even if the film thickness of the inorganic material 130 is large, disconnection of the electrode 140 is prevented.

  An inorganic insulating material is used for the inorganic material 130. For example, the inorganic material 130 is a single film or a stacked film such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or an aluminum oxide film. A silicon nitride film is desirable because of its high density. Moreover, the inorganic material 130 can improve airtightness by using a laminated film. The inorganic material 130 is not limited to the above, and an inorganic resin material may be used.

  The hole diameter of the through hole 115 may be set as appropriate between the inorganic material 130 and the through hole 115, but is preferably 1 to 4 times the thickness of the inorganic material 130. . As a result, the inorganic material can have a sufficient thickness, and can have sufficient airtightness against the gas retained in the slit 125.

  The electrode 140 is in contact with the first surface 110 </ b> A of the substrate 110, the upper surface 120 </ b> A of the through electrode 120, and the inorganic material 130. Note that the electrode 140 is not necessarily in contact with the first surface 110 </ b> A of the substrate 110.

  The inorganic material 150 is provided in contact with the second surface 110B of the substrate 110 and a part of the upper surface 120B of the through electrode 120. In addition, the inorganic material 150 covers the end portion 120 </ b> D of the through electrode 120 and the slit 125, similarly to the inorganic material 130. In addition, the inorganic material 150 has an opening 155 on the upper surface 120 </ b> B of the through electrode 120. (In FIG. 2, the slit 125 is greatly illustrated on the drawing for easy understanding.)

  The electrode 160 is in contact with the upper surface 120 </ b> B of the through electrode 120 and the inorganic material 150. The electrode 160 may be in contact with the second surface 110B of the substrate 110.

(1-3. Manufacturing method of through electrode substrate)
Next, a method for manufacturing the through electrode substrate 100 shown in FIG. 2 will be described with reference to FIGS.

  First, as shown in FIG. 3, a substrate 110 having a first surface 110A and a second surface 110B opposite to the first surface 110A is used. For example, as the substrate 110, a soda glass substrate, a non-alkali glass substrate, or a silicon substrate is used.

  Next, as shown in FIG. 4, a through hole 115 is formed in the substrate 110. The through hole 115 is formed by using, for example, a laser irradiation method (which can be referred to as a laser ablation method) for the substrate 110. As the laser, an excimer laser, a neodymium: yag laser (Nd: YAG) laser, a femtosecond laser, or the like is used. When an excimer laser is used, light in the ultraviolet region is irradiated. For example, when xenon chloride is used in an excimer laser, light having a wavelength of 308 nm is irradiated. The diameter of the through hole 115 may be set as appropriate by controlling the laser irradiation, but is preferably in the range of 10 μm to 100 μm. By using the above method, the through hole 115 has a circular shape when viewed from above. A plurality of through holes 115 may be provided.

The formation of the through-hole 115 is not limited to the laser irradiation method, and a dry etching method such as a reactive ion etching method or a deep reactive ion etching method, a wet etching method, or a laser irradiation method may be used. And a wet etching method may be used in combination. As an etchant for the wet etching method, any of hydrofluoric acid (HF), nitric acid (HNO ₃ ), and an alkaline solution may be used. For example, when wet etching a glass substrate, hydrofluoric acid is used. Further, when etching a silicon substrate, an alkaline solution or nitric acid and hydrofluoric acid are used. The through hole 115 may have a rectangular shape or a tapered shape in a cross-sectional view.

  Next, as shown in FIG. 5, the through electrode 120 is formed in the through hole 115. In addition to copper (Cu), nickel (Ni), gold (Au), silver (Ag), tin (Sn), or the like is used for the through electrode 120.

  The through electrode 120 is formed by the following method. First, a thin film of copper (Cu) is formed on the second surface 110B of the substrate 110 by a sputtering method. Next, a copper (Cu) film is formed by an electrolytic plating method using a copper (Cu) thin film as a seed layer. At this time, since the copper (Cu) film grows not only in the epitaxial direction but also in the lateral direction, the bottom 115B (see FIG. 4) of the through hole 115 is covered. (This film may be referred to as a lid plating film 117, see FIG. 5).

  Next, as shown in FIG. 6, the through electrode 120 is formed by filling the through hole 115 with a copper (Cu) film by electrolytic plating using the lid plating film 117 as a seed layer. Finally, the portion of the upper surface 120A of the through electrode 120 exposed from the first surface 110A of the substrate 110 and the lid plating film 117 are removed by a chemical mechanical polishing (CMP) method.

  Note that, at the stage of forming the through electrode 120, the adhesion between the substrate 110 and the through electrode 120 is small. Therefore, for example, when heat treatment is performed, a slit 125 is generated between the end portion 120C of the through electrode 120 and the side wall 115A of the through hole 115 due to a difference in thermal expansion coefficient, a change in stress, and the like. (In FIG. 6, the slit 125 is greatly illustrated for easy understanding.)

  Next, as shown in FIG. 7, an inorganic material 130 is formed. The inorganic material 130 is formed by a CVD (Chemical Vapor Deposition) method, a sputtering method, or a vapor deposition method. For example, the inorganic material 130 is formed of a single film or a laminated film of an inorganic film such as silicon oxide or silicon nitride.

  Note that the inorganic material 130 may be an organic-inorganic hybrid resin containing silica. The inorganic material 130 is processed into a predetermined shape by a combination of a photolithography method, an etching method, and the like. At this time, an opening 135 is formed on the through electrode 120 with respect to the inorganic material 130. The inorganic material 130 covers a part of the first surface 110A of the substrate 110 by processing. Thereby, the stress concentration of the inorganic material 130 can be relaxed.

  The hole diameter of the through hole 115 may be set as appropriate between the inorganic material 130 and the through hole 115, but is preferably 1 to 4 times the thickness of the inorganic material 130. . As a result, the inorganic material can have a sufficient thickness, and can have sufficient airtightness against the gas retained in the slit 125. The inorganic material 130 may be formed to have a tapered shape on the side surface. Thereby, when forming the subsequent electrode 140, a disconnection can be prevented.

  Next, as shown in FIG. 8, 140 is formed on the first surface 110 </ b> A of the substrate 110, the upper surface 120 </ b> A of the through electrode 120, and the insulating layer 140. The electrode 140 is formed using a plating method, a sputtering method, a vapor deposition method, a printing method, an etching method, or the like. The electrode 140 is made of copper (Cu) nickel (Ni), gold (Au), silver (Ag), tin (Sn), aluminum (Al), tungsten (W), titanium (Ti) or molybdenum (Mo). . For example, the electrode 140 is a copper (Cu) film formed by a plating method.

  Next, the inorganic material 150 and the electrode 160 are formed on the second surface 110 </ b> B of the substrate 110. The inorganic material 150 is formed in the same manner as the inorganic material 130. The electrode 160 is formed in the same manner as the electrode 140. The through electrode substrate 100 is manufactured by the above method.

  The through-electrode substrate 100 is manufactured by the above-described structure and method, and thus can have high airtightness even if gas is retained in the slit 125. For this reason, the pressure of the space 300 inside the mechanical quantity sensor 10 shown in FIG. 1 can be made constant. Therefore, the mechanical quantity sensor using the through electrode substrate 100 can stably exhibit its function. Further, the through electrode 120, the inorganic material 130, and the substrate 110 are arranged in this order at the end of the through hole 115. As a result, the stress applied to the vicinity of the end of the through-hole 115 in the inorganic material 130 is dispersed during formation of the through-electrode substrate (particularly during heat treatment), thereby preventing defects (cracks) in the inorganic material 130 or peeling of the inorganic material 130 from the film. Is done.

  9A is a top view between A1 and A2 of the through electrode substrate 100-1, and FIG. 9B is a cross-sectional view between A1 and A2 of the through electrode substrate 100-1.

  In FIG. 9B, the upper surface 120A-1 on the first surface 110A side and the upper surface 120B-1 on the second surface 110B side of the substrate 110 of the through electrode 120 each have a dish-like concave shape. This shape is due to dishing that occurs when the through electrode 120 is polished by a CMP method with a metal film (for example, a copper (Cu) film). At this time, as a result of applying a strong pressure to the through electrode 120, the width of the slit 125-1 may be larger than the width of the slit 125 of the through electrode substrate 100. In such a case, gas flow may be facilitated. However, since the through electrode substrate 100-1 includes the inorganic material 130 and the inorganic material 150, the end portion 120C and the slit 125-1 of the through electrode 120 can be sufficiently covered. For this reason, the penetration electrode substrate 100-1 can further have the effect in addition to having high airtightness. Therefore, the pressure of the space 300 inside the mechanical quantity sensor 10 can be made constant, so that the function of the mechanical quantity sensor 10 can be stably exhibited.

Second Embodiment
(2-1. Configuration of the through electrode substrate)
Next, through electrode substrates having different structures will be described. In addition, about the structure, material, and method which were shown in 1st Embodiment, the description is used.

  FIG. 10A shows a top view between A1 and A2 of the through electrode substrate 100-2. FIG. 10B shows a cross-sectional view between A1 and A2 of the through electrode substrate 100-2.

  As shown in FIG. 10B, the through electrode substrate 100 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130-2, an electrode 140, an inorganic material 150-2, and an electrode 160.

  In the through electrode substrate 100-2, a slit may not be provided completely or slightly between the side surface 120E of the through electrode 120 and the side wall 115A of the through hole 115 (in FIG. 2B). Described as slit 125-2). Even in this case, the gas during formation may stay.

  The inorganic material 130-2 is provided in contact with the first surface 110A of the substrate 110 and the upper surface 120A of the through electrode 120. At this time, the inorganic material 130-2 covers the end 120C (and the slit 125-2) of the through electrode 120.

  An inorganic insulating material is used for the inorganic material 130-2. In this example, a film in which an inorganic film 131 and an inorganic film 133 are stacked is used as the inorganic material 130. At this time, a silicon nitride film is used as the inorganic film 131. For the inorganic film 133, a silicon oxide film is used. At this time, the thickness of the inorganic film 133 is preferably 1 to 30 times, more preferably 2 to 20 times the thickness of the inorganic film 131. This is because the stress of the silicon nitride film is larger than the stress of the silicon oxide film.

The silicon nitride film used for the inorganic film 131 is formed using a SiH ₄ gas, an NH ₃ gas, or the like by a plasma CVD method. A silicon oxide film used for the inorganic film 133 is formed by a plasma CVD method using SiH ₄ gas, N ₂ O gas, or the like.

  The inorganic material 150-2 is provided in contact with the second surface 110B of the substrate 110 and the upper surface 120B of the through electrode 120. Further, the inorganic material 150-2 covers the end portion 120 </ b> D and the slit 125 of the through electrode 120, similarly to the inorganic material 130.

  An inorganic insulating material is used for the inorganic material 150-2. In this example, a film in which an inorganic film 151 and an inorganic film 153 are stacked is used as the inorganic material 150-2, similarly to the inorganic material 130-2. At this time, a silicon nitride film is used as the inorganic film 151. For the inorganic film 153, a silicon oxide film is used.

  Since the silicon nitride film used as the inorganic film 131 and the inorganic film 151 has high density, gas flow is prevented. That is, the airtightness of the through electrode can be increased.

  On the other hand, particularly when in contact with or close to the substrate 110, stress is applied to the end 120C and the end 120D of the through electrode 120 due to the difference between the thermal expansion coefficient of the substrate 110 and the thermal expansion coefficient of the through electrode 120. It is easy to concentrate and the inorganic material 130 and the inorganic material 150 may be damaged. At this time, as shown in FIG. 10B, the inorganic material 130 and the inorganic material 150 are laminated films, so that stress can be relaxed (controlled). Thereby, damage to the inorganic material 130 and the inorganic material 150 is prevented while ensuring airtightness.

<Third Embodiment>
(3-1. Configuration of the through electrode substrate)
Next, the through electrode substrate 100-3 having a different structure will be described. In addition, about the structure, material, and method shown in 1st Embodiment and 2nd Embodiment, the description is used suitably.

  FIG. 11 is a cross-sectional view taken along the line A1-A2 of the through electrode substrate 100-3. As shown in FIG. 11, the through electrode substrate 100-3 includes a substrate 110, a through hole 115, a through electrode 121, and an inorganic material 130-3.

  The underlayer 113 is provided on the first surface 110 </ b> A, the second surface 110 </ b> B, and the side wall 115 </ b> A of the through hole 115 of the substrate 110. The underlayer 113 includes a metal oxide. For example, zinc oxide is used as the metal oxide. The foundation layer 113 has a function of improving the adhesion between the substrate 110 and the third electrode 140.

  The through electrode 121 is provided on the base layer 113. The through electrode 121 includes a seed layer 122.

  The inorganic material 130-3 is provided in contact with the base layer 113 A on the first surface 110 A side of the substrate 110 and the upper surface 121 A of the through electrode 121. At this time, the inorganic material 130 covers the through hole 115 and the boundary portion 121E between the through electrode 121 and the base layer 113.

  In addition, the hole diameter of the through-hole 115 may be appropriately set between the inorganic material 130-3 and the through-hole 115, but is preferably 1 to 4 times the thickness of the inorganic material 130-3. It is desirable that At this time, the inorganic material 130-3 has a thickness sufficient to cover the boundary portion 121E between the through electrode 121 and the base layer 113.

  When the film thickness of the inorganic material 130-3 is large, the inorganic material 130-3 can cover the through hole 115 on the first surface 110A side of the substrate 110 as described above. In addition, the inorganic material 130-3 has an opening 135 in the upper surface 120 </ b> A of the through electrode 120.

  An inorganic insulating material is used for the inorganic material 130-3. In this example, a film in which an inorganic film 131 and an inorganic film 133 are stacked in this order is used as the inorganic material 130-3. At this time, a silicon nitride film is used as the inorganic film 131. For the inorganic film 133, a silicon oxide film is used. At this time, the thickness of the inorganic film 133 is 1 to 30 times, preferably 2 to 20 times the thickness of the inorganic film 131.

  With the above structure, the movement of a fluid such as gas existing between the through electrode 121 and the substrate 110 can be suppressed, and the pressure inside the mechanical quantity sensor 10 can be made constant.

(3-2. Manufacturing method of through electrode substrate)
Next, the manufacturing method of the penetration electrode substrate 100-3 is shown in FIGS.

  First, as shown in FIG. 12, the base layer 113 is formed on the side wall of the through hole 115, the first surface 110 </ b> A and the second surface 110 </ b> B of the substrate 110. The underlayer 113 is formed by an immersion method. The base layer 113 includes a metal oxide. For example, zinc oxide is used as the metal oxide. Specifically, the base layer 113 is formed by immersing the substrate 110 in a solution containing zinc acetate dihydrate. Heat treatment may be performed after the formation of the base layer 113.

  Next, as shown in FIG. 13, a seed layer 122 is formed on the first surface 110 </ b> A, the second surface 110 </ b> B, and the through hole 115 of the substrate 110. The seed layer 122 is formed by an electroless plating method. The seed layer 122 includes copper (Cu). Note that nickel (Ni) or gold (Au) may be used for the seed layer 122 as a material other than copper.

  The electroless plating method will be described below. When performing electroless plating, a conditioner, an activator, a metal salt, a reducing agent, a complexing agent, or the like is used. The conditioner is used as a pretreatment agent. The conditioner is used to make the Pd catalyst easily adhere to the surface of the underlayer 113. The activator is used to form a Pd catalyst on the surface. A metal salt is a material for depositing a metal. For example, when performing copper plating, copper sulfate is used. The reducing agent is used to reduce the metal salt. As the reducing agent, dimethylaminoborane (DMAB), formaldehyde, hydrazine hydrochloride, hydrazine sulfate, or the like is used. The complexing agent is used to control the deposition rate of the metal film. As the complexing agent, ethylenediaminetetraacetic acid (EDTA), Rochelle salt (L-potassium sodium tartrate tetrahydrate), citrate ion or the like is used. Moreover, before performing electroless plating, you may perform a degreasing process. Moreover, you may heat-process after an electroless-plating process.

  Next, as illustrated in FIG. 14, a resist film 127 is formed on the seed layer 122. The resist film 127 may be a coated film or a dry film resist. The resist film 127 is processed into a predetermined shape by photolithography.

  Next, as shown in FIG. 15, the through electrode 121 is formed on the exposed seed layer 125. The through electrode 121 is formed by an electrolytic plating method. The through electrode 121 is subjected to conformal plating. A copper (Cu) film is used for the through electrode 121. The method for forming the through electrode is called a semi-additive method. After the through electrode 121 is formed, the resist film 127 is removed. The resist film 127 may be removed by a chemical solution or may be removed by a dry etching method.

  Next, as shown in FIG. 16, the seed layer 122 provided under the resist film 127 is removed. At this time, the seed layer 122 is removed by a wet etching method. The above method is called a semi-additive method. By using the above method, the through electrode 121 can be formed thick.

  Next, as shown in FIG. 17, the inorganic material 130 is formed on the first surface 110 </ b> A side of the substrate 110 so as to be in contact with the base layer 113 and the upper surface 121 </ b> A of the through electrode 121. At this time, the inorganic material 130 covers the through hole 115 and the boundary portion 121 </ b> E between the through electrode 121 and the base layer 113.

  An inorganic insulating material is used for the inorganic material 130-3. In this example, a film in which an inorganic film 131 and an inorganic film 133 are stacked is used as the inorganic material 130-3. A silicon nitride film is used as the inorganic film 131. As the inorganic film 133, a silicon oxide film is used. At this time, the thickness of the inorganic film 133 is preferably 1 to 30 times, more preferably 2 to 20 times the thickness of the inorganic film 131. This is because the stress of the silicon nitride film is larger than the stress of the silicon oxide film.

In this example, the inorganic material 130-3 is formed by a plasma CVD method. The silicon nitride film used for the inorganic film 131 is formed using SiH ₄ gas and NH ₃ gas. The silicon oxide film used for the inorganic film 133 is formed using SiH ₄ gas and N ₂ O gas. Note that the inorganic film 131 and the inorganic film 133 may be formed by a sputtering method, an evaporation method, or a printing method.

  In addition, the hole diameter of the through-hole 115 may be appropriately set between the inorganic material 130-3 and the through-hole 115, but is preferably 1 to 4 times the thickness of the inorganic material 130-3. It is desirable that At this time, the inorganic material 130-3 has a sufficient thickness. Thereby, on the first surface 110A side of the substrate 110 described above, the inorganic material 130-3 grows not only in the epitaxial direction but also in the lateral direction. Thereby, the inorganic material 130-3 can cover the through hole 115.

  The inorganic material 130-3 is processed into a predetermined shape by combining a photolithography method and an etching method. At this time, the opening 135 is formed on the through electrode 121 with respect to the inorganic material 130-3.

  Through the above method, the through electrode substrate 100-3 shown in FIG. 11 is manufactured.

  In the through electrode substrate 100-3 manufactured by the above method, heat treatment is performed between the base layer 113 and the through electrode 121 (particularly between the base layer 113 and the seed layer 122), so that the metal and A difference in coefficient of thermal expansion may occur with the metal oxide. Thereby, distortion (stress concentration) occurs, and the adhesion between the through electrode and the underlying layer may not be sufficient. (For example, one may be tensile stress and the other may be compressive stress.) For this reason, a gap is generated at the boundary (interface) between the base layer 113 and the through electrode 121, and a fluid such as gas is generated. May be movable. However, the silicon nitride film used as the inorganic film 131 of the inorganic material 130-3 provided on the through electrode substrate 100-3 has high density. The inorganic material 130-3 has a sufficiently large thickness. For this reason, the flow of gas at the boundary (interface) between the base layer 113 and the through electrode 121 is prevented.

  Moreover, the through-hole 115 is completely covered with the inorganic material 130-3. That is, by having the inorganic material 130-3, the airtightness of the through electrode substrate can be improved.

  Note that the inorganic material 130 is a laminated film, so that stress can be relaxed (controlled). For example, a tensile stress is given to the silicon nitride film of the inorganic film 131, and a compressive stress is given to the silicon oxide film. By controlling the stress in this manner, generation of defects (cracks, film peeling, etc.) in the inorganic material 130-3 is suppressed.

<Fourth embodiment>
(4-1. Configuration of the through electrode substrate)
Next, the through electrode substrate 100-4 having a different structure will be described. In addition, about the structure, material, and method shown in 1st-3rd embodiment, the description is used suitably.

  FIG. 18 is a cross-sectional view taken along the line A1-A2 of the through electrode substrate 100-4. As shown in FIG. 18, the through electrode substrate 100-4 includes a substrate 110, a through hole 115, a through electrode 120, an inorganic material 130, and a filler 170.

  The filler 170 is provided in the through hole 115. The filler 170 is in contact with the side surface of the through electrode 120. The filler 170 includes an inorganic resin material. In addition, the filler 170 may include inorganic particles. The inorganic particles have a size of, for example, several tens of nm to several tens of μm. The inorganic particles include silica, alumina and the like.

  The filler 170 is filled and formed in the through hole 115 so as to be in contact with the side surface of the through electrode 121. The filler 170 is formed by a sol-gel method, an ink jet method, or an immersion method. After forming the filler 170, heat treatment may be appropriately performed. Thereby, a filler can be made denser.

(Modification 1)
In the third embodiment, as the inorganic material 130-3, an example in which a laminated film of a silicon nitride film and a silicon oxide film is used is shown, but the present invention is not limited to this. A sintered body may be used for the inorganic material 130-3. For example, an inorganic sintered body (ceramics) may be used as the sintered body.

(Modification 2)
In 1st Embodiment, although the upper surface of the penetration electrode 120 showed the example which has a concave shape, it is not limited to this. For example, filling plating is performed on a substrate having a bottomed shape (sometimes referred to as a hole glass substrate), and the substrate is filled from the non-bottomed surface side (second surface side) until the filled metal material is exposed. The penetrating electrode 120 may be formed by polishing. In that case, the hole shape of the bottomed structure is not a rectangular structure but a pointed shape. Then, the filling plating shape also has a pointed (convex shape) shape. At this time, the upper surface of the through electrode may be convex.

  DESCRIPTION OF SYMBOLS 10 ... Mechanical quantity sensor, 100 ... Through-electrode board, 110 ... Substrate, 113 ... Underlayer, 115 ... Through-hole, 117 ... Lid plating film, 120 ... Through-electrode 121 ... Through electrode, 122 ... Seed layer, 125 ... Slit, 127 ... Resist film, 130 ... Inorganic material, 131 ... Inorganic film, 133 ... Inorganic film, 135 ... Opening part, 140 ... Electrode, 150 ... Inorganic material, 151 ... Inorganic film, 153 ... Inorganic film, 155 ... Opening part, 160 ... Electrode, 170 ..Filling material, 210 ... substrate, 215 ... opening, 220 ... insulating layer, 230 ... conductive layer, 235 ... thin film, 250 ... region, 300 ... space

Claims (19)

A substrate having a first surface, a second surface opposite to the first surface, and a through hole;
A through electrode filled in the through hole;
A slit disposed between a side surface of the through electrode and a side wall of the through hole;
On the first surface side of the substrate, the edge of the through electrode and the slit are covered, a part of the upper surface of the through electrode and the first surface of the substrate are in contact, and a first opening is formed on the through electrode A first inorganic material having a part;
On the second surface side of the substrate, the edge of the through electrode and the slit are covered, a part of the upper surface of the through electrode and the second surface of the substrate are in contact, and a second opening is formed on the through electrode A second inorganic material having a part,
Through electrode substrate. The inorganic material is in contact with a side wall of the through hole;
The through electrode substrate according to claim 1. The upper surface of the through electrode has a dish-like concave shape,
The through electrode substrate according to claim 1. A substrate having a first surface, a second surface opposite to the first surface, and a through hole;
An underlayer provided on the first surface, the second surface and the side wall of the through hole of the substrate;
A through electrode provided on the underlayer;
The first surface side of the substrate covers the boundary between the through hole and the through electrode and the base layer, is in contact with the upper surface of the through electrode and the first surface of the substrate, and has an opening on the through electrode. A first inorganic material having
Through electrode substrate. The diameter of the through hole is 1 to 4 times the thickness of the first inorganic material.
The through electrode substrate according to claim 4. The first inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order,
The thickness of the second inorganic film is 1 to 30 times the thickness of the first inorganic film.
The through electrode substrate according to claim 1. The first inorganic film is a silicon nitride film,
The second inorganic film is a silicon oxide film.
The through electrode substrate according to claim 6. The first inorganic material is a sintered body.
The through electrode substrate according to claim 4. Further comprising a filler provided in the through hole and in contact with the through electrode on a side surface;
The through electrode substrate according to any one of claims 4 to 8. A conductive layer in contact with the first surface of the substrate, an upper surface on the first surface side of the through electrode, and the first inorganic material;
The through electrode substrate according to claim 1. Forming a base layer on the first surface of the substrate, the second surface opposite to the first surface, and the side wall of the through hole;
A through electrode is formed so as to be in contact with the base layer,
On the first surface side of the substrate, an inorganic material is formed so as to cover the boundary between the through hole and the through electrode and the base layer, and to be in contact with the upper surface of the through electrode and the base layer,
For the inorganic material, forming an opening on the through electrode,
A manufacturing method of a penetration electrode substrate containing. The diameter of the through-hole is 1 to 4 times the thickness of the inorganic material.
The manufacturing method of the penetration electrode substrate of Claim 11. The inorganic material is a film in which a first inorganic film and a second inorganic film are laminated in this order,
The thickness of the second inorganic film is 1 to 30 times the thickness of the first inorganic film.
The manufacturing method of the penetration electrode substrate of Claim 12. The first inorganic film of the inorganic material is a silicon nitride film;
The second inorganic film of the inorganic material is a silicon oxide film;
The manufacturing method of the penetration electrode substrate of Claim 13. The inorganic material is formed by a plasma CVD method.
The manufacturing method of the penetration electrode substrate of Claim 14. The inorganic material is a sintered body.
The manufacturing method of the penetration electrode substrate of Claim 11. Forming a filler so as to be in contact with a side surface of the through electrode in the through hole,
The manufacturing method of the penetration electrode substrate as described in any one of Claims 11 thru | or 16. The underlayer is formed by a dipping method.
The manufacturing method of the penetration electrode substrate as described in any one of Claims 11 thru | or 17. Including the through electrode substrate according to claim 1,
Mechanical quantity sensor.