JP2008137139A - Micro-electromechanical device and manufacturing method thereof - Google Patents

Abstract

A microelectromechanical device having excellent reliability and a method for manufacturing the same are provided.
A microelectromechanical structure 3 formed on a substrate 2, a frame member 4 formed on the substrate 2 so as to surround the microelectromechanical structure 3, and the frame member 4 are covered. A cavity forming film 6 that forms a cavity 5 between the micro electro mechanical structure 3 and a seal layer that is laminated on the cavity forming film 6 and seals the micro electro mechanical structure 3 in the cavity 5. And a stop layer 7.
[Selection] Figure 1

Description

  The present invention relates to a microelectromechanical device in which a microelectromechanical structure (MEMS element) such as a micromechanical relay, an acceleration sensor, a pressure sensor, and an actuator is sealed, and a method for manufacturing the same.

  2. Description of the Related Art In recent years, attention has been focused on MEMS (Micro Electro Mechanical System) elements manufactured by using a semiconductor manufacturing process such as LSI and other ultra-fine processing processes. The MEMS element is hermetically sealed in order to protect the element from the influence of the outside world as in a normal semiconductor device. However, since the MEMS element must hold the element in a hollow state due to its operating characteristics, it is necessary to apply a sealing structure that can hold the hollow state. As such a sealing structure, a metal cap type package that has been conventionally applied is known. However, since an increase in the size of the package is inevitable, it is possible to meet the recent demand for downsizing. Can not.

  In response to such a problem, a sacrificial layer covering the MEMS element is formed, a cavity forming film having a through hole leading to the sacrificial layer is laminated on the sacrificial layer, and then the sacrificial layer is selectively removed from the through hole. And the structure which laminated | stacked the sealing layer so that the through-hole of a cavity formation film was plugged up, and sealed the MEMS element was proposed (for example, refer patent document 1). In this way, the MEMS element is sealed with the cavity necessary for its operating characteristics held around by the sealing material composed of the cavity forming film and the sealing layer.

However, in the conventional sealing structure, for example, when these are packaged with a mold resin in order to protect the wiring layer on the substrate from the external environment, the strength of the sealing material against the mold pressure is not sufficient, Breaking the base, cracking, etc. And when a sealing material contacts a MEMS element, it will become a factor which degrades an element characteristic.
JP-A-2005-123561

  An object of the present invention is to provide a microelectromechanical device excellent in reliability and a method for manufacturing the same.

  A microelectromechanical device according to an aspect of the present invention includes a microelectromechanical structure formed on a substrate, a frame member formed on the substrate so as to surround the microelectromechanical structure, A cavity-forming film that covers a frame member and forms a cavity between the micro-electromechanical structure and a seal that is laminated on the cavity-forming film and seals the micro-electromechanical structure in the cavity And a layer.

  In addition, a method for manufacturing a microelectromechanical device according to one embodiment of the present invention includes a step of forming a microelectromechanical structure on a substrate, a sacrificial member that covers the microelectromechanical structure, and the substrate surface. Forming a frame member surrounding the sacrificial member, a cavity forming film covering the sacrificial member and the frame member so that at least one of the frame member and the cavity forming film has a through hole, and the sacrificial member through the through hole And a step of laminating a sealing layer on the cavity forming film after removing the sacrificial member.

  With the above configuration, it is possible to provide a microelectromechanical device having excellent reliability and a method for manufacturing the same.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, although embodiment of this invention is described below based on drawing, those drawings are provided for illustration and this invention is not limited to those drawings.

  FIG. 1 is a cross-sectional view schematically showing the configuration of a microelectromechanical device (hereinafter referred to as a MEMS device) according to a first embodiment of the present invention.

  As shown in FIG. 1, the MEMS device 1 according to the first embodiment includes a MEMS element 3 formed on a substrate 2, a frame member 4 formed on the substrate 2 so as to surround the MEMS element 3, and A cavity forming film 6 that covers the frame member 4 and forms a cavity 5 with the MEMS element 3 and a sealing layer 7 laminated on the cavity forming film 6 are provided. Further, a wiring layer 8 such as a signal line, a power supply line, and a ground line for operating the MEMS element 3 is formed on the substrate 2. As the substrate 2, for example, an insulating substrate such as glass or synthetic resin or a semiconductor substrate such as silicon can be used. When a semiconductor substrate is used, the wiring layer 8 is disposed on the substrate 2 via an insulating layer (not shown). It is formed.

  As the MEMS element 3, a cantilever relay configured by a cantilever 3 a and a cantilever support portion 3 b can be applied. The cantilever 3a is composed of a metal thin film or the like. The cantilever support 3b is made of, for example, silicon nitride, aluminum oxide, titanium oxide, or an insulating resin, and is obtained by processing into a predetermined shape by a photolithography method, a dry etching method, or the like. For example, an electrostatic microswitch, electrostatic microrelay, micromechanical relay, acceleration sensor, pressure sensor, or actuator can be applied to the MEMS element 3.

  The frame member 4 is formed on the substrate 2 so as to surround the MEMS element 3. The shape of the frame member 4 includes, for example, a quadrangle, a circle, an ellipse, and the like as an outer shape when viewed in plan, and may be any other shape, but from the viewpoint of work efficiency and impact resistance, a quadrangle ( B-shaped) is preferable. The material constituting the frame member 4 may be any material as long as it can easily form a desired frame shape and is difficult to peel off when a sacrificial layer described later is etched away in the manufacturing process of the MEMS device 1. The frame member 4 is made of, for example, SiN (silicon nitride), polysilicon (poly-Si), or the like, and can be formed using a CVD (Chemical Vapor Deposition) method or the like.

  The cavity forming film 6 is formed so as to form a cavity 5 necessary for operating characteristics of the MEMS element 3 on the inner side thereof and cover the frame member 4. As the shape of the cavity forming film 6, for example, a frustum shape obtained by excising the top of a cone such as a cone, a hexagonal pyramid, a quadrangular pyramid, or a hemispherical (dome) shape can be given. In this embodiment, the shape is a square frustum shape, and has a through hole 9 in the flat portion (center portion). The cavity forming film 6 is made of, for example, SiN or the like, and is formed by sputtering, CVD, vapor deposition, or the like.

  The sealing layer 7 is stacked on the cavity forming film 6. In the present embodiment, it is formed so as to block the through hole 9 provided in the flat portion of the cavity forming film 6. The shape of the sealing layer 7 is the same shape as that of the cavity forming film 6, and in this embodiment is a square frustum shape. The sealing layer 7 can be formed by the same material and forming method as the cavity forming film 6.

  The wiring layer 8 is formed on the substrate 2, is electrically connected to the MEMS element 3, and exchanges electric signals and the like with the outside. For the wiring layer 8, for example, a metal thin film made of Au, Cr, Rt, Ti, Ni, Al, Cu, or the like, an alloy thin film thereof, a conductor thin film in which these layers are laminated, or the like can be applied. In this case, a metal thin film or the like is formed by a sputtering method, a metal vapor deposition method, or the like, and then patterned by photolithography or the like. The form of the wiring layer 8 is not particularly limited, and can be appropriately selected according to required specifications such as a coplanar line, a microstrip line, a grounded coplanar line, or a simple thin film signal line.

  The MEMS device 1 of the present embodiment described above is manufactured as follows, for example. 2A to 2C and FIGS. 3D to 3F are process diagrams schematically showing a method for manufacturing the MEMS device 1 shown in FIG.

First, as shown in FIG. 2A, a metal thin film made of Al or the like is formed on a substrate 2 by a sputtering method or the like, and then patterned by a photolithography method or the like to form a wiring layer 8. A sacrificial layer 10 made of, for example, SiO ₂ is formed so as to cover a part of the wiring layer 8, and the MEMS element 3 including the cantilever 3a and the cantilever support portion 3b is formed. Next, a rectangular frame member 4 made of SiN or the like is patterned by a CVD method, then a photolithography method or the like so as to surround the sacrificial layer 10 on which the MEMS element 3 is formed.

Next, as shown in FIG. 2B, a sacrificial layer 11 made of the same material (SiO ₂ ) as the sacrificial layer 10 is laminated on the sacrificial layer 10 so as to cover the square-shaped frame member 4. Then, an organic insulating film such as a resist 12 is formed on the sacrificial layer 11 by coating or the like. The resist 12 is used as a mask material in the subsequent taper etching, and is also used for forming the cavity forming film 6 as a sacrificial member together with the sacrificial layers 10 and 11. Subsequently, using the resist 12 as a mask material, the sacrificial layer 11 is processed into a square frustum shape by taper etching under the condition that taper etching is performed. The taper etching is performed by dry etching such as reactive ion etching (RIE). In this taper etching, the taper angle can be adjusted to a desired angle by controlling the gas conditions of the etching gas. In the taper etching, as the etching progresses, the resist 12 retreats and the thickness of the resist 12 decreases, but at least the upper surface of the sacrificial layer 11 is covered with the resist 12 after the etching is completed. The thickness of the resist 12 to be formed first is preferably determined.

  Thereafter, as shown in FIG. 2C, the cavity forming film 6 made of SiN or the like is used by sputtering, CVD, or the like so as to cover the frame member 4, the sacrificial layer 11 that has been processed in shape, and the resist 12 as a whole. To form a film.

  As shown in FIG. 3D, a part of the cavity forming film 6, here, a part of the upper surface is removed by using a photolithography method, a dry etching method or the like, and the sacrificial layers 10 and 11 and the resist 12 are removed. A through hole 9 is formed in the cavity forming film 6. The through-hole 9 is provided so as to avoid a portion directly above the MEMS element 3 so that the formation of the through-hole 9 and subsequent etching or the like do not adversely affect the characteristics of the MEMS element 3.

Next, the resist 12 is removed by ashing from the through-hole 9 provided in the cavity forming film 6, and then an etchant such as buffer hydrofluoric acid that can selectively dissolve and remove the sacrificial layers 10 and 11 made of SiO _{2 is} removed. Then, the sacrificial layers 10 and 11 are removed, and a cavity 5 is formed around the MEMS element 3 as shown in FIG. The resist 12 can also be removed by a wet etching method. When the sacrificial layers 10 and 11 are made of SiO ₂ , an RIE method, a dry etching method using hydrofluoric acid vapor, or the like can be used in addition to the wet etching method. Thereafter, as shown in FIG. 3F, a sealing layer 7 made of SiN or the like is laminated on the cavity forming film 6 by using a sputtering method, a CVD method or the like, and the through holes 9 of the cavity forming film 6 are formed. The MEMS element 3 is sealed by closing.

  As described above, according to the present embodiment, the rectangular frame member 4 is formed so as to surround the MEMS element 3, and the sealing composed of the cavity forming film 6 and the sealing layer 7 is formed so as to cover the frame member 4. By forming the stoppers, even when these are packaged with a mold resin, they are resistant to impacts and stresses, and cracks and the like are unlikely to occur at the base of the sealing material. For this reason, it is possible to provide the MEMS device 1 with high sealing reliability capable of reliably sealing the MEMS element 3 in the cavity 5.

  Further, the sacrificial layer 11 can be easily processed into a frustum shape by taper etching by the RIE method.

The sacrificial layers 10 and 11 may be made of a synthetic resin such as a polyimide resin. In this case, as the cavity forming film 6, the sacrificial layer 11 is not easily damaged by the film forming process of the cavity forming film 6, and from the viewpoint of the selectivity of etching between the sacrificial layer 11 and the cavity forming film 6, ₂ etc. can also be applied. The sacrificial layers 10 and 11 made of polyimide resin can be removed by ashing through the through holes 9 provided in the cavity forming film 6. Therefore, the sacrificial layers 10 and 11 as the sacrificial members and the resist 12 applied to the sacrificial layers 10 and 11 can be collectively removed by ashing.

  The sacrificial layer 11 has a frustum shape such as a square frustum, but may have a dome (hemispherical) shape. In this case, the sacrificial layers 10 and 11 can be formed in a dome shape by forming them with a photoresist or the like and annealing at about 300 ° C. By making such a frustum shape or hemispherical shape, the cavity forming film 6 and the sealing layer 7 are formed in a subsequent process as compared with the case where the side wall of the sacrificial layer 11 is formed substantially perpendicular to the substrate 2. To provide a MEMS device 1 that can be laminated on the sacrificial layer 11 with a substantially uniform film thickness in each part (base and upper part), can improve the strength of the sealing material, and is excellent in sealing reliability. Can do.

  Next, the MEMS device according to the second embodiment will be described with reference to FIG. FIG. 4 is a cross-sectional view schematically showing the configuration of the MEMS device 21 according to the second embodiment of the present invention. Similar to the first embodiment, the MEMS device 21 according to the present embodiment includes a square frame member 23, a frustum-shaped cavity forming film 24, and a sealing layer 7. The form is different in that a through hole 22 for etching away the sacrificial layers 10 and 11 is provided on the side wall of the frame member 23. The same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is simplified or omitted.

  As shown in FIG. 4, the MEMS device 21 according to the second embodiment includes a MEMS element 3 formed on a substrate 2 and a frame member that is formed so as to surround the MEMS element 3 and that has a through hole 22 on a side wall thereof. 23, a cavity forming film 24 that covers the frame member 23 and forms the cavity 5 with the MEMS element 3, and a sealing layer 7 laminated on the cavity forming film 24.

  The MEMS device 21 of the present embodiment described above is manufactured as follows, for example. FIGS. 5A to 5C and FIGS. 6D to 6F are process views schematically showing a method for manufacturing the MEMS device 21 shown in FIG. FIG. 7 schematically shows the frame member 23 formed in the manufacturing process of the MEMS device 21 according to the second embodiment of the present invention and the through-hole forming film 25 for forming a through-hole in the frame member 23. It is a top view.

  First, as shown in FIG. 5A, the wiring layer 8 is formed on the substrate 2. A sacrificial layer 10 made of, for example, a polyimide resin is formed so as to cover a part of the wiring layer 8, and the MEMS element 3 including the cantilever 3a and the cantilever support portion 3b is formed.

Next, as shown in FIG. 5B, a through hole forming film 25 for forming the through hole 22 in the frame member 23 is formed on the substrate 2, and the through hole forming film 24 is made of SiO _2. The square-shaped frame member 23 is formed by patterning so as to surround the MEMS element 3 by a CVD method, then a photolithography method or the like. When the through hole forming film 25 and the frame member 23 are viewed in plan, a part of the frame member 23 is laminated on the through hole forming film 25 as shown in FIG. The through-hole forming film 25 is made of a polyimide resin that is the same material as the sacrificial layer 10.

  Subsequently, as shown in FIG. 5C, the sacrificial layer 11 made of polyimide is laminated on the sacrificial layer 10 so as to cover the frame member 23, and an organic insulating film such as a resist 12 is applied. . Next, in the same manner as in the first embodiment described above, the sacrificial layer 11 is processed into a frustum shape by taper etching.

As shown in FIG. 6D, a cavity forming film 24 made of SiO ₂ or the like is formed by sputtering, CVD or the like so as to cover the frame member 23, the sacrificial layer 11 and the resist 12 that have been processed. Film.

  Next, as shown in FIG. 6E, the through-hole forming film 25 made of polyimide is removed by ashing, and the sacrificial layers 11 and 11 that are sacrificial members and the sacrificial layer 11 for removing the resist 12 are led. A through hole 22 is formed. Subsequently, the sacrificial layers 10 and 11 made of polyimide and the resist 12 are sequentially removed from the through holes 22 by ashing to form a cavity 5 around the MEMS element 3.

Next, as shown in FIG. 6 (f), a sealing layer 7 made of SiO ₂ or the like is formed on the cavity forming film 24 using an HDP (High Density Plasma) method or the like, and the side wall of the frame member 23 is formed. The MEMS element 3 is sealed by closing the through-hole 22 provided in.

  As described above, according to the present embodiment, the rectangular frame member 23 is formed so as to surround the MEMS element 3, and the sealing formed of the cavity forming film 24 and the sealing layer 7 is formed so as to cover the frame member 23. By forming the stoppers, even when these are packaged with a mold resin, they are resistant to impacts and stresses, and cracks and the like are unlikely to occur at the base of the sealing material. For this reason, it is possible to provide the MEMS device 21 with high sealing reliability capable of reliably sealing the MEMS element 3 in the cavity 5.

  In addition, by providing the through hole 22 in the frame member 23 instead of directly above the MEMS element 3, unnecessary foreign matters are less likely to adhere to the MEMS element 3 during the formation of the through hole 22 or in an etching process, thereby improving the manufacturing yield. be able to.

  Further, by applying polyimide to the sacrificial layers 10 and 11, when removing the sacrificial layers 10 and 11 and the resist 12 from the through-hole 22, the sacrificial layers 10 and 11 and the resist 12 are collectively removed by ashing. The manufacturing process can be simplified.

  Next, a MEMS device according to a third embodiment will be described with reference to FIG. FIG. 8 is a cross-sectional view schematically showing the configuration of the MEMS device 31 according to the third embodiment of the present invention. The MEMS device 31 shown in the figure is different from the first and second embodiments described above in that an electrode 32 made of Cu is formed around the MEMS element 3 as the frame members 4 and 23. In addition, the same code | symbol is attached | subjected to the component same as 1st and 2nd embodiment, and the description is simplified or abbreviate | omitted.

  As shown in FIG. 8, the MEMS device 31 of the third embodiment includes a MEMS element 3 formed on the substrate 2 and an electrode 32 made of Cu formed on the substrate 2 so as to surround the MEMS element 3. Formed on the electrode 32, having a through hole 33, a cavity forming film 34 forming the cavity 5 between the MEMS element 3, and a layer formed on the cavity forming film 34 so as to block the through hole 33. The sealing layer 35 is provided.

  The electrode 32 is electrically connected to the wiring layer 8 formed on the substrate 2 and acts as a lead-out line for wiring on the substrate 2, and exchanges electric signals and the like with the outside. The electrode 32 is made of Cu, and is formed by a damascene method or the like. The electrode 32 is formed in a square shape so as to surround the MEMS element 3, but an insulating film 36 made of SiN or the like is provided between a part of the electrode 32 and the wiring layer 8 to prevent a short circuit. .

  The MEMS device 31 of the present embodiment described above is manufactured as follows, for example. FIGS. 9A to 9C and FIGS. 10D to 10F are process diagrams schematically showing an example of a method for manufacturing the MEMS device 31 shown in FIG.

First, as shown in FIG. 9A, the wiring layer 8 is formed on the substrate 2. A sacrificial layer 10 made of, for example, SiO _{2 is formed} so as to cover a part of the wiring layer 8, and the MEMS element 3 including the cantilever 3a and the cantilever support portion 3b is formed. Next, an insulating material such as SiN is formed on the wiring layer 8 by, for example, sputtering or CVD, and patterned to form the insulating film 36.

Next, as shown in FIG. 9B, a sacrificial layer 11 made of SiO ₂ or the like is formed so as to cover a part of the wiring layer 8 and the insulating film 36.

  Thereafter, as shown in FIG. 9C, an electrode 32 is formed by a damascene method. That is, a square-shaped groove is formed in the sacrificial layer 11 so as to surround the MEMS element 3, and a Cu film is formed on the sacrificial layer 11 so that Cu is embedded in the groove, and then CMP (Chemical Mechanical Polishing) is performed. An unnecessary Cu film is removed by the method to form the electrode 32. The width of the electrode 32 is set to be smaller than that of the insulating film 36 in consideration of positional deviation.

  As shown in FIG. 10D, a cavity forming film 34 made of SiN or the like is formed on the electrode 32 and the sacrificial layer 11. The cavity forming film 34 is also used as a mask material in the sacrificial layer etching in the next step. As the mask material, sacrificial layer etching is possible, and since it remains in the MEMS device 31 as a cavity forming film 34 that finally forms the cavity 5 with the MEMS element 3, an inorganic material is preferable. SiN etc. are mentioned.

  A through hole 33 leading to the sacrificial layer 11 for etching away the sacrificial layers 10 and 11 is formed in the cavity forming film 34 by using a photolithography method, a dry etching method, or the like. Next, the sacrificial layers 10 and 11 are removed by etching through the through holes 33 to form the cavities 5 around the MEMS element 3 (FIG. 10E).

  As shown in FIG. 10 (f), a sealing layer 35 made of SiN or the like is formed using an HDP method or the like so as to cover the cavity forming film 34 and the electrode 32, and the through hole 33 of the cavity forming film 34 is formed. The MEMS element 3 is sealed by closing. Thereafter, a through hole (not shown) for wire bonding to the electrode 32 is formed in the sealing layer 35, and an external bonding pad (not shown) and the electrode 32 are wire bonded. That is, one bonding wire 37 is bonded to the electrode 32, and the other bonding wire 38 is bonded to the wiring layer 8 on the substrate 2.

  As described above, according to the present embodiment, the electrode 32 made of Cu is used as a lead line for wiring on the substrate 2, and when the whole is packaged with a mold resin, the impact and stress are sealed. Since it also acts as a reinforcing member for the material, the sealing element is pressed and broken, so that the MEMS element 3 can be reliably sealed in the cavity 5 without sticking to the MEMS element 3. A device 31 can be provided.

  As shown in FIG. 10F, one bonding wire 37 is bonded to the electrode 32, and the other bonding wire 38 is bonded to the wiring layer 8 on the substrate 2. For example, as shown in FIG. Thus, wire bonding can also be performed. That is, the insulating layer 36 made of SiN or the like as shown in FIG. 8 is not formed on the wiring layer 8 on the substrate 2, and the electrode 32 shown in FIG. It has a shape as shown in FIG.

Next, a MEMS device according to a fourth embodiment will be described with reference to FIG. FIG. 13 is a cross-sectional view schematically showing the configuration of a MEMS device 41 according to the fourth embodiment of the present invention. The MEMS device 41 shown in the figure is different from the third embodiment described above in that the electrode 42 has a barrier layer 43 made of MnSi _x O _{y on} its side wall. In addition, the same code | symbol is attached | subjected to the component same as 1st thru | or 3rd embodiment, and the description is simplified or abbreviate | omitted.

As shown in FIG. 13, the MEMS device 41 of the fourth embodiment has a barrier layer 43 made of MnSi _x O _{y on} the side wall of the electrode 42. The electrode 42 has a shape as shown in FIG. 12 when viewed in a plan view to prevent a short circuit.

  The MEMS device 41 of the present embodiment described above is manufactured as follows, for example. FIGS. 14A to 14C, 15D to 15F, and FIG. 16G are process diagrams schematically showing an example of a method for manufacturing the MEMS device 41 shown in FIG. .

First, as shown in FIG. 14A, the wiring layer 8 is formed on the substrate 2. A sacrificial layer 10 made of, for example, SiO _{2 is formed} so as to cover a part of the wiring layer 8 to form the MEMS element 3 including a cantilever and a cantilever support portion. A part of the wiring layer 8 is covered, and a sacrificial layer 11 made of the same material (SiO ₂ ) is laminated on the sacrificial layer 10 described above.

  Next, as shown in FIG. 14B, a trench is formed in the sacrificial layer 11 so as to surround the MEMS element 3, and sacrifice is performed by CVD or the like so that a Cu alloy such as Cu—Mn is embedded in the trench. A Cu alloy film 44 is formed on the layer 11. In this case, the groove is formed in a shape as shown in FIG. 12 when viewed in plan.

Thereafter, heat treatment is performed at 200 to 350 ° C. As a result, as shown in FIG. 14C, a barrier layer 43 made of MnSi _x O _y is formed at the interface between the Cu alloy film 44 and the sacrificial layer 11. The film thickness of the barrier layer 43 is preferably about 2 to 3 nm. The Cu alloy film 44 may be a Cu film by removing the Mn component of Cu—Mn by heat treatment.

  As shown in FIG. 15D, the unnecessary Cu alloy film 44 (or Cu film) and the barrier metal film 43 are removed and planarized by CMP to form the electrode 42.

  A cavity forming film 34 made of SiN or the like is formed (FIG. 15E). As shown in FIG. 15F, the sacrificial layers 10 and 11 are removed from the cavity forming film 34 by etching. A through-hole 33 communicating with the layer 11 is formed using a photolithography method, a dry etching method, or the like. Next, the sacrificial layers 10 and 11 are removed by etching from the through holes 33 to form the cavities 5 around the MEMS elements 3.

  As shown in FIG. 16G, a MEMS layer is formed by forming a sealing layer 35 made of SiN or the like on the cavity forming film 34 using a CVD method or the like, and closing the through holes 33 of the cavity forming film 34. 3 is sealed. Thereafter, a through hole (not shown) for wire bonding to the electrode 42 is formed in the sealing layer 35, and an external bonding pad (not shown) and the electrode 42 are wire bonded.

As described above, according to the present embodiment, the sacrificial layer is formed by using the Cu alloy such as Cu—Mn for the electrode 42 and forming the barrier layer 43 provided on the side wall of the electrode 42 from MnSi _x O _y. Even when an O ₂ gas is used when 10 and 11 are removed by dry etching, oxidation of the barrier layer 43 and the electrode 42 can be avoided. Therefore, it is possible to prevent the strength of the electrode 42 from deteriorating, and to suppress an increase in resistance when the electrode 42 is used as a lead line for each wiring. Therefore, the reliability of the MEMS device 41 can be improved.

  Similarly to the above-described embodiment, the electrode 42 is used as a lead-out line for each wiring on the substrate 2 and as a reinforcing member for a sealing material against the impact and stress when the whole is packaged with a mold resin. Therefore, it is possible to provide the MEMS device 41 with high sealing reliability capable of reliably sealing the MEMS element 3 in the cavity 5.

  The present invention is not limited to the description of the above embodiment, and can be appropriately changed without departing from the gist of the present invention. For example, the materials, structures, shapes, substrates, processes, etc. mentioned in the first to fourth embodiments are merely examples, and if necessary, materials, structures, shapes, substrates, processes, etc. different from these. May be used.

1 is a cross-sectional view schematically showing a configuration of a MEMS device according to a first embodiment of the present invention. Process drawing which shows the manufacturing process of the MEMS apparatus shown in FIG. 1 with a typical cross section. Process drawing which shows the manufacturing process of the MEMS apparatus shown in FIG. 1 with a typical cross section. Sectional drawing which shows typically the structure of the MEMS apparatus which concerns on the 2nd Embodiment of this invention. Process drawing which shows the manufacturing process of the MEMS apparatus shown in FIG. 4 with a typical cross section. Process drawing which shows the manufacturing process of the MEMS apparatus shown in FIG. 4 with a typical cross section. The top view which shows typically the frame member 23 and the through-hole formation film 25 which were formed in the manufacturing process of the MEMS device which concerns on the 2nd Embodiment of this invention. Sectional drawing which shows typically the structure of the MEMS apparatus which concerns on the 3rd Embodiment of this invention. Process drawing which shows the manufacturing process of the MEMS device shown in FIG. Process drawing which shows the manufacturing process of the MEMS device shown in FIG. Sectional drawing which shows typically the modification of the MEMS apparatus shown in FIG. The top view which shows typically the electrode 32 applied to the MEMS apparatus shown in FIG. Sectional drawing which shows typically the structure of the MEMS apparatus which concerns on the 4th Embodiment of this invention. Process drawing which shows the manufacturing process of the MEMS device shown in FIG. Process drawing which shows the manufacturing process of the MEMS device shown in FIG. Process drawing which shows the manufacturing process of the MEMS device shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 21, 31, 41 ... MEMS device, 2 ... Board | substrate, 3 ... MEMS element, 4, 23 ... Frame member, 5 ... Cavity, 6, 24, 34 ... Cavity formation film, 7, 35 ... Sealing layer, 8 ... wiring layer, 9, 22, 33 ... through hole, 10, 11 ... sacrificial layer, 12 ... resist, 25 ... through hole forming film, 32, 42 ... electrode, 36 ... insulating film, 37 ... bonding wire, 43 ... barrier Layer, 44 ... Cu alloy film.

Claims (5)

A microelectromechanical structure formed on a substrate;
A frame member formed on the substrate so as to surround the microelectromechanical structure;
A cavity-forming film that covers the frame member and forms a cavity with the micro-electromechanical structure;
A microelectromechanical device comprising: a sealing layer which is laminated on the cavity forming film and seals the microelectromechanical structure in the cavity.   The micro electromechanical device according to claim 1, wherein the cavity forming film has a frustum shape or a hemispherical shape.   The micro electromechanical device according to claim 1, wherein the frame member is an electrode made of Cu or a Cu alloy. The microelectromechanical device according to claim 3, wherein the electrode made of Cu or Cu alloy has a barrier layer made of MnSi _x O _{y on a} side wall thereof. Forming a microelectromechanical structure on a substrate;
A sacrificial member that covers the microelectromechanical structure, a frame member that surrounds the sacrificial member on the substrate surface, and a cavity forming film that covers the sacrificial member and the frame member, at least one of the frame member and the cavity forming film is a through hole Forming to have
Removing the sacrificial member through the through hole;
And a step of laminating a sealing layer on the cavity forming film after removing the sacrificial member.

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