Flexible skin incorporating mems technology

{
  "publication_number": "US6071819A",
  "country": "US",
  "kind": "A",
  "title": "Flexible skin incorporating mems technology",
  "abstract": "A flexible skin formed of silicon islands encapsulated in a polyimide film. The silicon islands preferably include a MEMS device and are connected together by a polyimide film (preferably about 1-100 μm thick). To create the silicon islands, silicon wafers are etched to a desirable thickness (preferably about 10-500 μm) by Si wet etching and then patterned from the back side by reactive ion etching (RIE).",
  "claims": [
    "1. A method of manufacturing a flexible microelectronic device comprising: first etching a lower side of a wafer using a first caustic agent; depositing a first layer of aluminum on an upper side of the wafer; patterning the first layer of aluminum; depositing a first layer of polyimide on the upper side of the wafer, covering the first layer of aluminum; depositing a second layer of aluminum on the upper side of the wafer, covering the first layer of polyimide; depositing a second layer of polyimide on the upper side of the wafer, covering the second layer of aluminum; depositing a third layer of aluminum on the lower side of the wafer; patterning the third layer of aluminum; second etching the lower side of the wafer using the third layer of aluminum as a mask and the first layer of aluminum as an etch stop and using a less caustic agent than said first caustic agent, such that the wafer is divided into islands with gaps surrounding each island; and depositing a third layer of polyimide on the lower side of the wafer, such that the gaps are at least partially filled.",
    "2. The method of claim 1 where the first etching is TMAH etching.",
    "3. The method of claim 1 where the first etching is KOH etching.",
    "4. The method of claim 1 where the second etching is vertical reactive ion etching.",
    "5. The method of claim 1 which further comprises forming at least one MEMS device on the upper side of at least one of the islands.",
    "6. The method of claim 5 where at least one of the MEMS devices is a shear stress sensor."
  ],
  "cpc": [
    "B81B 7/0077",
    "B81C 1/00246",
    "H10W 90/10"
  ],
  "assignees": [
    "CALIFORNIA INST OF TECHN"
  ],
  "filing_date": "1998-01-23",
  "publication_date": "2000-06-06",
  "grant_date": "2000-06-06",
  "priority_date": "1997-01-24",
  "application_number": "US-1275698-A",
  "family_id": "21887547",
  "citations": [
    "US4587719A",
    "US4634495A",
    "US5199298A",
    "US5511428A",
    "US5883310A"
  ]
}