JP2010073886A - Semiconductor device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor device capable of preventing deformation of a sealing film for sealing a recess where a movable part of a functional element is arranged, and to provide a method of manufacturing the same. <P>SOLUTION: The semiconductor device includes: a semiconductor chip 10 having a recess 15 on a surface 10a, and equipped with a functional element 100 having a column 11 having a lower end contacting the bottom of the recess 15 and a movable part disposed in the recess 15 so as to surround the column 11; a columnar part 202 disposed on the upper end of the column 11; a spacer 20 having an annular part 201 annularly disposed surrounding the recess 15 on the surface 10a of the semiconductor chip 10; and a sealing film 30 contacting the upper surface 202a of the columnar part 202 of the spacer 20 and the upper surface 201a of the annular part 201 thereof, and disposed so as to cover the upper part of the recess 15 so as to form a cavity. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor device having a functional element having a movable part, and more particularly to a semiconductor device having a sealing film for sealing a concave portion in which the movable part is arranged, and a method for manufacturing the same.

  MEMS (Micro Electro Mechanical System) elements having functional elements having movable parts, surface acoustic wave (SAW) elements, piezoelectric thin film resonators (FBARs) using piezoelectric materials, etc. are used for gyro sensors, pressure sensors, etc. Yes. Generally, in a MEMS element, a SAW element, an FBAR, and the like, a movable part such as a vibrator is formed on a semiconductor chip.

When the movable part of the functional element is disposed in the recess formed on the surface of the semiconductor chip, it is necessary to seal the concave part to protect the movable part of the functional element. This is to prevent the characteristic variation of the functional element. For example, the concave portion is sealed with a sealing film such as a resin (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-19924

  However, since the resin sealing film has low strength, the sealing film may be deformed when the semiconductor chip is molded and sealed. In this case, there is a problem in that the movable portion of the functional element disposed in the recess and the sealing film come into contact with each other, and the functional element is damaged. In order to mold-seal the semiconductor chip without deforming the sealing film above the recess, it is necessary to increase the thickness of the sealing film to, for example, about several hundreds μm, which hinders the thinning of the semiconductor device.

  In view of the above problems, an object of the present invention is to provide a semiconductor device that can suppress deformation of a sealing film that seals a recess in which a movable part of a functional element is disposed, and a method for manufacturing the same.

  According to one aspect of the present invention, there is provided (i) a functional element having a concave portion formed on a surface thereof, a support portion having a lower end in contact with a bottom surface of the concave portion, and a movable portion disposed in the recess so as to surround the support portion. A semiconductor chip provided; (b) a columnar portion disposed on the upper end of the support column; a spacer having an annular portion disposed in an annular shape surrounding the recess on the surface of the semiconductor chip; and (c) a columnar portion of the spacer. And a sealing film disposed in contact with the upper surface of the substrate and the upper surface of the annular portion and covering the upper portion of the recess so as to form a cavity.

  According to another aspect of the present invention, (b) a step of forming a recess on the surface of the semiconductor chip and a column part contacting the lower end with the bottom surface of the recess, and (b) being disposed in the recess so as to surround the column part. Forming a functional element having a movable part; (c) a spacer having a columnar part arranged on the upper end of the support part and an annular part arranged in an annular shape surrounding the recess on the surface of the semiconductor chip; And (d) a method of manufacturing a semiconductor device, including: (d) disposing a sealing film covering the upper surface of the columnar portion of the spacer and the upper surface of the annular portion so as to form a cavity. Is done.

  ADVANTAGE OF THE INVENTION According to this invention, the semiconductor device which can suppress the deformation | transformation of the sealing film which seals the recessed part which has arrange | positioned the movable part of a functional element, and its manufacturing method can be provided.

  Next, first to fourth embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Also, the following first to fourth embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is the component parts. The material, shape, structure, arrangement, etc. are not specified below. The technical idea of the present invention can be variously modified within the scope of the claims.

(First embodiment)
As shown in FIG. 1, the semiconductor device according to the first embodiment of the present invention has a recess 15 formed on the surface 10 a, and surrounds the support 11 and the support 11 that is in contact with the bottom of the recess 15. The semiconductor chip 10 including the functional element 100 having a movable portion disposed in the recess 15, the columnar portion 202 disposed on the upper end of the support column 11, and the recess 10 on the surface 10 a of the semiconductor chip 10 are surrounded. The spacer 20 having the annular portion 201 arranged in an annular shape, and the seal 20 arranged in contact with the upper surface 202a of the columnar portion 202 of the spacer 20 and the upper surface 201a of the annular portion 201 and covering the upper portion of the recess 15 so as to form a cavity. A stop film 30.

  In the example shown in FIG. 1, the semiconductor chip 10 has a structure in which a first silicon film layer 101, a silicon oxide film layer 102, and a second silicon film layer 103 are stacked. As will be described later, a part of each of the second silicon film layer 103 and the silicon oxide film layer 102 is removed by etching, so that the support part 11 and the movable part of the functional element 100 are formed. That is, the bottom surface of the recess 15 is the surface 101 a of the first silicon film layer 101. The upper end surface of the column part 11 is located on the same plane level as the surface 10a of the semiconductor chip 10 and the upper surface of the movable part. Of course, the movable part of the functional element 100 may be formed by other methods. The electrode pad 151 disposed on the surface 10a of the semiconductor chip 10 is used for applying a voltage to the movable part of the functional element 100, outputting a detection signal generated by the functional element 100, and the like, as will be described later.

  For the spacer 20, for example, a resin adhesive such as polyimide, epoxy, acrylic, or silicone can be used. A resin adhesive that can be screen-printed or applied can be used for the spacer 20.

  For the sealing film 30, for example, a resin film such as a photosensitive resin film can be employed. The film thickness of the sealing film 30 is about several tens to one hundred μm. The film thickness of the sealing film 30 is determined in accordance with the area and shape of the recess 15 and the number and arrangement of the column parts 11 disposed in the recess 15.

  In the semiconductor device shown in FIG. 1, in addition to the annular part 201 arranged on the surface 10 a of the semiconductor chip 10 so as to surround the concave part 15, a columnar part arranged on the upper end of the column part 11 arranged in the concave part 15. The sealing film 30 is supported by 202. For this reason, for example, even if pressure is applied to the sealing film 30 above the recess 15 from above, deformation of the sealing film 30 can be suppressed.

  For example, when the shape of the periphery of the recess 15 formed at a depth of 50 μm is a rectangle of 1 mm × 1 mm, a rectangular column part 11 having an upper end surface shape of 50 μm × 50 μm is disposed near the center of the recess 15. Although FIG. 1 illustrates the case where there is one support column 11, a plurality of support columns 11 may be arranged in the recess 15.

  The “movable part” of the functional element 100 is a part where the shape is physically changed or the position is changed according to an external factor such as an external impact. For example, a vibrator of a pressure sensor or a gyro sensor is a movable part.

  FIG. 2 shows an example of a movable part included in the functional element 100. Here, an example in which the functional element 100 is an acceleration sensor will be described. FIG. 2 is a top view of the semiconductor device shown in FIG. FIG. 1 is a cross-sectional view taken along the II direction of FIG. As shown in FIG. 2, the movable part of the functional element 100 has cantilever beams 1111 to 1116 having a fixed end fixed to the inner surface of the recess 15 and a free end extending from the fixed end to the space formed by the recess 15. 1121 to 1123, 1131 to 1136, and 1141 to 1143, and the central movable portion 105 disposed in the central region of the recess.

  The cantilevers 1111 to 1116 extend upward toward the paper surface. The cantilever beams 1121 to 1123 extend leftward toward the paper surface. The cantilever beams 1131 to 1136 extend downward toward the paper surface. The cantilever beams 1141 to 1143 extend rightward toward the paper surface. Hereinafter, the cantilever beams 1111 to 1116, 1121 to 1123, 1131 to 1136, and 1141 to 1143 are collectively referred to as “outer peripheral beam portions” 110.

  A cavity is formed in the central region of the central movable part 105, and the column part 11 is disposed through the cavity. The four corners of the central movable portion 105 are fixed to the inner surface of the recess 15 by support portions 1051 to 1054. Cantilever beams 1011 to 1015, 1021 to 1024, 1031 to 1035, and 1041 to 1044 are arranged on the four outer edges of the central movable portion 105. Hereinafter, the cantilever beams 1011 to 1015, 1021 to 1024, 1031 to 1035, and 1041 to 1044 arranged on the outer edge portion of the central movable portion 105 are collectively referred to as “central beam portions” 106.

  As shown in FIG. 2, the cantilever beams 1111 to 1116 and the cantilever beams 1011 to 1015 are arranged in a crossed finger shape. Similarly, the cantilever beams 1121 to 1123 and the cantilever beams 1021 to 1024, the cantilever beams 1111 to 1136 and the cantilever beams 1031 to 1035, and the cantilever beams 1141 to 1143 and the cantilever beams 1041 to 1044 are arranged in a crossed finger shape. Has been.

  FIG. 3 shows a cross-sectional view along the direction III-III in FIG. The silicon oxide film layer 102 in the recess 15 is etched away, and the outer peripheral beam portion 110 and the central beam portion 106 obtained by patterning the second silicon film layer 103 are formed.

  An example of the operation of the semiconductor chip 10 shown in FIG. 1 will be described below. When an external force is applied to the semiconductor chip 10 while a voltage is applied between the central beam portion 106 and the outer peripheral beam portion 110, the central beam portion 106 and the outer peripheral beam portion 110 are mechanically vibrated by the influence of the external force, and the central beam portion. The inter-beam distance between 106 and the peripheral beam portion 110 varies. The functional element 100 detects a change in electrostatic capacitance between the central beam portion 106 and the outer peripheral beam portion 110 caused by displacement of the movable part. That is, the mechanical displacement of the movable part of the functional element 100 is detected as a change in capacitance. The functional element 100 generates the detected change in capacitance as a detection signal. By processing the detection signal, the acceleration generated in the semiconductor chip 10 is detected. Voltage application to the central beam portion 106 and the outer peripheral beam portion 110 and output of detection signals to the outside are performed via electrode pads 151 to 153 arranged on the surface 10a of the semiconductor chip 10 and the like.

  As shown in FIGS. 1 and 3, the position of the upper surface of the functional element 100 and the position of the surface 10a of the semiconductor chip 10 are on the same plane level. The central beam portion 106 and the outer peripheral beam portion 110 vibrate mechanically. For this reason, the spacer which separates the semiconductor chip 10 and the sealing film 30 so that the central beam part 106 or the outer peripheral beam part 110 and the sealing film 30 do not contact even if the central beam part 106 and the outer peripheral beam part 110 vibrate. The thickness d of 20 needs to be a certain size. The value of the thickness d is set according to the vibration width of the central beam portion 106 and the outer peripheral beam portion 110 determined according to the material and shape. The thickness d of the spacer 20 is set to about several tens of μm, for example, about 50 μm.

  In the semiconductor device according to the first embodiment of the present invention, the sealing film 30 on the semiconductor chip 10 is supported by the spacer 20 having the annular portion 201 and the columnar portion 202. Therefore, according to the semiconductor device shown in FIG. 1, even if pressure is applied to the sealing film 30 from above the concave portion 15 in which the movable part of the functional element 100 is arranged, the sealing film 30 that seals the concave portion 15 is provided. Deformation can be suppressed. As a result, the problem of contact between the movable part of the functional element 100 and the sealing film 30 can be prevented. According to the semiconductor device shown in FIG. 1, the semiconductor device can be made thinner than when the sealing film 30 is supported only by the annular portion 201 disposed in the peripheral region of the recess 15.

  A method of manufacturing the semiconductor device shown in FIG. 1 will be described with reference to FIGS. The semiconductor device manufacturing method described below is merely an example, and it is needless to say that the present invention can be realized by various other manufacturing methods including this modification.

  (A) As shown in FIG. 4, a silicon oxide film 211 is formed on the surface 10a of the semiconductor chip 10 on which the first silicon film layer 101, the silicon oxide film layer 102, and the second silicon film layer 103 are laminated by a thermal oxidation method or the like. Form.

  (B) A part of the silicon oxide film 211 is removed by etching using a photolithography technique or the like using a photoresist film as a mask, and the silicon oxide film 211 is patterned. Specifically, as shown in FIG. 5, the silicon oxide film 211 is left on the region where the central beam portion 106 and the outer peripheral beam portion 110 are formed, and on the region where the column portion 11 is formed. The silicon oxide film 211 on the region where the electrode pads 151 to 153 are arranged is removed.

  (C) An aluminum (Al) film is disposed on the surface 10 a of the semiconductor chip 10. By patterning the Al film using a photolithography technique or the like, an electrode pad 151 is formed on the surface 10a of the semiconductor chip 10 as shown in FIG.

  (D) As shown in FIG. 7, the second silicon film layer 103 is removed by etching using the silicon oxide film 211 as a mask to form side portions of the central movable portion 105 and the outer peripheral beam portion 110. At this time, the central region of the central movable portion 105 is opened, and the side surface portion of the support column 11 is formed at the same time.

  (E) The silicon oxide film 211 and the silicon oxide film layer 102 are removed by etching. At this time, as shown in FIG. 8, using the second silicon film layer 103 as a mask, the silicon oxide film layer 102 is removed by etching until the surface 101a of the first silicon film layer 101 is exposed. As a result, the central beam portion 106 and the outer peripheral beam portion 110 are formed. At the same time, the support column 11 is formed. That is, the functional element 100 having the column portion 11 that contacts the bottom surface of the concave portion 15 and the movable part disposed in the concave portion 15 so as to surround the column portion 11 is formed. The upper end surface of the column portion 11 having a structure in which the second silicon film layer 103 and the second silicon film layer 103 are laminated is located on the same plane level as the surface 10a of the semiconductor chip 10 and the upper surface of the movable portion.

  (F) As shown in FIG. 9, a columnar portion 202 disposed on the upper end surface of the column portion 11 and an annular portion 201 disposed in an annular shape surrounding the recess 15 on the surface 10 a of the semiconductor chip 10 are formed. For example, the epoxy resin is screen printed with a thickness of about 50 μm, and the epoxy resin is thermally cured. From the above, the spacer 20 having the columnar portion 202 and the annular portion 201 is formed.

  (G) The sealing film 30 is disposed so as to cover the upper portion of the columnar portion 202 of the spacer 20 and the upper surface of the annular portion 201 so as to form a cavity. For example, after laminating a photosensitive resin sheet on the semiconductor chip 10, a part of the photosensitive resin sheet is removed by etching using a photolithography technique or the like, and the sealing film 30 having a desired pattern is disposed. Thus, the semiconductor device shown in FIG. 1 is completed.

  As described above, according to the manufacturing method of the semiconductor device according to the first embodiment of the present invention, the sealing film 30 on the semiconductor chip 10 is supported by the spacer 20 having the annular portion 201 and the columnar portion 202. An improved semiconductor device is provided. That is, it is possible to provide a semiconductor device that can suppress deformation of the sealing film 30 that seals the recess 15 even when pressure is applied to the sealing film 30 from above the recess 15 in which the movable part of the functional element 100 is disposed.

  FIG. 10 shows an example in which the semiconductor device shown in FIG. 1 is arranged on the substrate 40 and the semiconductor device is molded and sealed with a mold resin 50. The substrate 40 is a printed wiring board or the like. The electrode pad 151 disposed on the semiconductor chip 10 and the electrode pad 451 disposed on the substrate 40 are connected by a bonding wire.

  As described above, in the semiconductor device shown in FIG. 10, even if the semiconductor chip 10 and the sealing film 30 are covered with the mold resin 50, the movable part and the sealing portion of the functional element 100 caused by the deformation of the sealing film 30 are sealed. Contact with the stop film 30 does not occur. According to the semiconductor device shown in FIG. 11, the molding resin 50 prevents foreign matter from entering into the recess 15 in which the movable part of the functional element 100 is disposed and moisture from entering. For this reason, the characteristics of the semiconductor chip 10 do not vary, and the yield of the semiconductor device is improved. Needless to say, the semiconductor chip 10 and the sealing film 30 may be covered with a sealing material other than the mold resin.

(Second Embodiment)
The semiconductor device according to the second embodiment of the present invention has a structure in which a signal processing semiconductor chip 60 is arranged on a sealing film 30 as shown in FIG. A processing circuit 600 is formed on the signal processing semiconductor chip 60. The processing circuit 600 receives a detection signal in which the functional element 100 detects a mechanical displacement of the movable part as a change in capacitance. Then, the processing circuit 600 detects the acceleration generated in the semiconductor chip 10 by processing the detection signal.

  The processing circuit 600 is formed on the front surface 60 a facing the back surface facing the sealing film 30 of the signal processing semiconductor chip 60. In the example shown in FIG. 11, the electrode pad 651 disposed on the surface 60a of the signal processing semiconductor chip 60 and the electrode pad 151 disposed on the surface 10a of the semiconductor chip 10 are wire-bonded to form the processing circuit 600. And the functional element 100 are electrically connected. In addition, the electrode pads 652 arranged on the surface 60a of the signal processing semiconductor chip 60 and the electrode pads 452 arranged on the surface 40a of the substrate 40 are wire-bonded to form a wiring pattern on the processing circuit 600 and the substrate 40. Are electrically connected.

  As already described, the sealing film 30 on the semiconductor chip 10 is supported by the spacer 20 having the annular portion 201 and the columnar portion 202. For this reason, even if pressure is applied to the sealing film 30 from above the recess 15, deformation of the sealing film 30 that seals the recess 15 can be suppressed. Therefore, as shown in FIG. 11, the signal processing semiconductor chip 60 can be disposed on the sealing film 30.

  When the signal processing semiconductor chip 60 is smaller than the area of the recess 15, the signal processing semiconductor chip 60 cannot cover the recess 15. However, by disposing the signal processing semiconductor chip 60 on the sealing film 30, the semiconductor chip 10 and the signal processing semiconductor chip 60 can be mounted in an overlapping manner.

  According to the semiconductor device shown in FIG. 11, the spacer 20 having the annular portion 201 and the columnar portion 202 is disposed on the semiconductor chip 10, so that the functional element can be applied even when pressure is applied to the sealing film 30 from above the recess 15. The movable part 100 and the sealing film 30 are not in contact with each other. Furthermore, by mounting the semiconductor chip 10 including the functional element 100 having a movable part and the signal processing semiconductor chip 60 for processing an electric signal due to the displacement of the movable part, the semiconductor device can be reduced in size. Others are substantially the same as those in the first embodiment, and redundant description is omitted.

(Third embodiment)
FIG. 12 shows a semiconductor device according to the third embodiment of the present invention. The semiconductor device shown in FIG. 12 does not have the semiconductor chip 10 provided with the functional element 100 and the signal processing semiconductor chip 60 that processes the electric signal due to the displacement of the movable part stacked and mounted, and the semiconductor chip 10 and the signal processing The semiconductor device 60 differs from the semiconductor device shown in FIG. 11 in that the semiconductor chip 60 is arranged on the substrate 40.

  When the chip thickness of the signal processing semiconductor chip 60 is thick, if the semiconductor chip 10 and the signal processing semiconductor chip 60 are arranged so as to overlap each other, the height of the entire semiconductor device exceeds a predetermined height, and the semiconductor device is There are cases where it becomes an obstacle to the implementation. As shown in FIG. 12, by arranging the semiconductor chip 10 and the signal processing semiconductor chip 60 side by side on the substrate 40, the height of the semiconductor device can be suppressed.

  According to the semiconductor device shown in FIG. 12, by disposing the spacer 20 having the annular portion 201 and the columnar portion 202 on the semiconductor chip 10, the functional element can be applied even when pressure is applied to the sealing film 30 from above the recess 15. The movable part 100 and the sealing film 30 are not in contact with each other. Further, when the signal processing semiconductor chip 60 is thick, the semiconductor chip 10 and the signal processing semiconductor chip 60 can be arranged on the same substrate 40. Others are substantially the same as those of the first and second embodiments, and redundant description is omitted.

(Fourth embodiment)
FIG. 13 shows a semiconductor device according to the fourth embodiment of the present invention. The semiconductor device shown in FIG. 13 is different from the semiconductor device shown in FIG. 1 in that a processing circuit 600 that processes an electrical signal due to displacement of a movable part is formed on a semiconductor chip 10 including a functional element 100. .

  Although not shown, the via 150, the functional element 100, and the processing circuit 600 are electrically connected by a wiring or the like disposed on the surface 10 a of the semiconductor chip 10. The functional element 100 and the processing circuit 600 are electrically connected to the substrate 40 via the via 150 and the bump 450 penetrating the semiconductor chip 10.

  According to the semiconductor device shown in FIG. 14, the functional element is formed even when pressure is applied to the sealing film 30 from above the recess 15 by disposing the spacer 20 having the annular portion 201 and the columnar portion 202 on the semiconductor chip 10. The movable part 100 and the sealing film 30 are not in contact with each other. Furthermore, the semiconductor device can be miniaturized by forming the processing circuit 600 on the semiconductor chip 10 and electrically connecting the semiconductor chip 10 and the substrate 40 by the bumps 450 without using bonding wires. Others are substantially the same as those in the first to third embodiments, and redundant description is omitted.

(Other embodiments)
As described above, the present invention has been described according to the first to fourth embodiments. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the description of the first to fourth embodiments already described, the functional element 100 formed on the semiconductor chip 10 is an acceleration sensor. However, the semiconductor chip 10 is a MEMS element other than the acceleration sensor, or For example, a SAW element or FBAR other than the MEMS element may be used.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

1 is a schematic diagram showing a configuration of a semiconductor device according to a first embodiment of the present invention. 1 is a top view of a semiconductor device according to a first embodiment of the present invention. It is sectional drawing along the III-III direction of the functional element shown in FIG. It is process sectional drawing for demonstrating the manufacturing method of the semiconductor device which concerns on the 1st Embodiment of this invention (the 1). FIG. 6 is a process cross-sectional view for explaining the manufacturing method of the semiconductor device according to the first embodiment of the present invention (No. 2). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor device which concerns on the 1st Embodiment of this invention (the 3). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor device which concerns on the 1st Embodiment of this invention (the 4). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor device which concerns on the 1st Embodiment of this invention (the 5). It is process sectional drawing for demonstrating the manufacturing method of the semiconductor device which concerns on the 1st Embodiment of this invention (the 6). It is a schematic diagram which shows the structure of the example which carried out mold sealing of the semiconductor device which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the structure of the semiconductor device which concerns on the 2nd Embodiment of this invention. It is a schematic diagram which shows the structure of the semiconductor device which concerns on the 3rd Embodiment of this invention. It is a schematic diagram which shows the structure of the semiconductor device which concerns on the 4th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Semiconductor chip 11 ... Support | pillar part 15 ... Recess 20 ... Spacer 30 ... Sealing film 40 ... Substrate 50 ... Mold resin 60 ... Signal processing semiconductor chip 100 ... Functional element 101 ... 1st silicon film layer 102 ... Silicon oxide film layer DESCRIPTION OF SYMBOLS 103 ... 2nd silicon film layer 105 ... Center movable part 201 ... Annular part 202 ... Columnar part 211 ... Silicon oxide film 600 ... Processing circuit 1011-1044 ... Cantilever 1051-1054 ... Support part 1111-1143 ... Cantilever

Claims (12)

A semiconductor chip provided with a functional element having a concave portion formed on the surface, a support portion in contact with a bottom end of the concave portion, and a movable portion disposed in the concave portion so as to surround the support portion;
A spacer having a columnar portion disposed on the upper end of the support column, and an annular portion disposed annularly around the recess on the surface of the semiconductor chip;
And a sealing film disposed in contact with the upper surface of the columnar portion and the upper surface of the annular portion of the spacer and covering the upper portion of the concave portion so as to form a cavity.   The semiconductor device according to claim 1, wherein the sealing film is a resin film.   The semiconductor device according to claim 1, wherein the spacer is a resin film.   4. The semiconductor device according to claim 1, wherein the surface of the semiconductor chip and the upper surface of the movable part are located on the same plane. 5.   The semiconductor device according to claim 1, wherein the semiconductor chip and the sealing film are molded and sealed with a resin.   2. The acceleration sensor according to claim 1, wherein the movable part is an acceleration sensor having a cantilever having a fixed end fixed to an inner surface of the recess and a free end extending from the fixed end to a space formed by the recess. The semiconductor device according to any one of 1 to 5.   The semiconductor device according to claim 1, wherein the functional element is any one of a MEMS element, a surface acoustic wave element, and a piezoelectric thin film resonator. Forming a recess on the surface of the semiconductor chip and a support column in contact with the bottom of the bottom of the recess;
Forming a functional element having a movable part disposed in the recess so as to surround the support column;
Forming a spacer having a columnar portion disposed on the upper end of the support column and an annular portion disposed in an annular shape surrounding the recess on the surface of the semiconductor chip;
And disposing a sealing film that covers the upper part of the recess so as to form a cavity and is in contact with the upper surface of the columnar part and the upper surface of the annular part of the spacer.   The step of forming the functional element includes a step of forming a cantilever in which a fixed end is fixed to an inner surface of the recess, and a free end extends from the fixed end to a space formed by the recess. A method for manufacturing a semiconductor device according to claim 8.   The method for manufacturing a semiconductor device according to claim 9, wherein a side surface of the support column and a side surface of the cantilever are formed simultaneously.   The method of manufacturing a semiconductor device according to claim 8, wherein the spacer is formed by a screen printing method.   The method for manufacturing a semiconductor device according to claim 8, further comprising a step of mold-sealing the semiconductor chip and the sealing film.

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