{
  "patent_number": "US RE42346",
  "country": "US",
  "title": "How Silicon Microphones Use Layers to Shrink Sound Sensors",
  "original_title": "USRE42346E1 - Solid state silicon-based condenser microphone",
  "summary": "A design for a tiny, silicon-based microphone that stacks a sound-sensing chip and an electronic processor chip together with an intermediate layer to save space.",
  "what_it_does": "This patent describes a way to build a microphone using silicon, the same material used for computer chips. It uses a tiny, flexible diaphragm that moves when sound waves hit it, creating a change in electrical charge between it and a fixed backplate. To make this small enough for devices like phones, the patent stacks the sensor chip on one side of an intermediate layer and an electronic processing chip (ASIC) on the other. A hole through this middle layer allows sound to reach the diaphragm, while electrical paths on the layer connect the two chips together.",
  "what_it_does_not_cover": [
    "Does not cover microphones that use traditional mechanical membranes instead of silicon-based diaphragms",
    "Does not cover microphones where the electronic circuit is placed side-by-side with the sensor rather than stacked",
    "Does not cover non-capacitive sensing methods like piezoelectric or optical microphones"
  ],
  "filed": "2002-07-11",
  "granted": "2011-05-10",
  "expires": null,
  "status": "active",
  "holder": "Epcos Pte Ltd",
  "holder_url": "https://patentbrief.org/company/epcos-pte-ltd",
  "inventors": [
    {
      "name": "Henrick Laurids Hvims",
      "url": "https://patentbrief.org/inventor/henrick-laurids-hvims"
    },
    {
      "name": "Maja Amskov Gravad",
      "url": "https://patentbrief.org/inventor/maja-amskov-gravad"
    },
    {
      "name": "Matthias Heschel",
      "url": "https://patentbrief.org/inventor/matthias-heschel"
    },
    {
      "name": "Siebe Bouwstra",
      "url": "https://patentbrief.org/inventor/siebe-bouwstra"
    },
    {
      "name": "Pirmin Rombach",
      "url": "https://patentbrief.org/inventor/pirmin-rombach"
    },
    {
      "name": "Ole Hansen",
      "url": "https://patentbrief.org/inventor/ole-hansen"
    },
    {
      "name": "Matthias Müllenborn",
      "url": "https://patentbrief.org/inventor/matthias-mllenborn"
    }
  ],
  "times_cited": 4,
  "tags": [
    "consumer_electronics",
    "semiconductors",
    "telecommunications"
  ],
  "abstract": "A solid state silicon-based condenser microphone comprising a silicon transducer chip ( 1 ). The transducer chip includes a backplate ( 13 ) and a diaphragm ( 12 ) arranged substantially parallel to each other with a small air gap in between, thereby forming an electrical capacitor. The diaphragm ( 12 ) is movable relative to the backplate ( 13 ) in response to incident sound. An integrated electronic circuit chip ( 3 ) or ASIC is electrically coupled to the transducer chip ( 1 ). An intermediate layer ( 2 ) fixes the transducer chip ( 1 ) to the integrated electronic circuit chip ( 3 ) with the transducer chip ( 1 ) on a first side of the intermediate layer ( 2 ) and the integrated electronic circuit chip ( 3 ) on a second side of the intermediate layer ( 2 ) opposite the first side. The intermediate layer ( 2 ) has a sound inlet ( 4 ) on the same side as the ASIC giving access of sound to the diaphragm.",
  "url": "https://patentbrief.org/patent/us/RE42346/cyclone-vacuum-cleaner",
  "markdown_url": "https://patentbrief.org/patent/us/RE42346/cyclone-vacuum-cleaner/md",
  "google_patents_url": "https://patents.google.com/patent/USRE42346",
  "relatedPatents": []
}