High density slider clamp fixture

{
  "publication_number": "US10655959B2",
  "country": "US",
  "kind": "B2",
  "title": "High density slider clamp fixture",
  "abstract": "A high density slider clamp fixture is disclosed for accurately positioning a large number of head sliders for metrology testing. The slider clamp fixture may include a single piece, monolithic structure comprising a large number of slider nests, aligned in rows and columns in the slider fixture. Each slider nest includes a reference datum surface machined to precisely align with all other reference datum surfaces in a row of the monolithic structure. Each slider nest further includes a flexure clamp for independent clamping of each slider in the row against the reference datum surfaces.",
  "claims": [
    "1. A clamp fixture for clamping a plurality of sliders, comprising: a monolithic structure comprising one or more rows of slider nests for receiving the plurality of sliders, a slider nest in a row comprising: a reference datum edge formed in the monolithic structure, the reference datum edge aligned with other reference datum edges in the row, and a flexure configured to clamp a slider of the plurality of sliders against the reference datum edge, the flexure configured to clamp the slider independently of other flexures in the row.",
    "2. The clamp fixture of claim 1, wherein the reference datum edge and flexure are configured to constrain the slider along a first axis, the slider nest further comprising a pair of sidewalls configured to guide the slider into the slider next along a second axis orthogonal to the first axis.",
    "3. The clamp fixture of claim 1, wherein the monolithic structure further comprises a base, the flexure machined into the monolithic from a surface opposed to the base down to the base.",
    "4. The clamp fixture of claim 3, wherein the monolithic structure further comprises a datum block extending from the base, the reference datum edge being machined into the datum block.",
    "5. The clamp fixture of claim 3, wherein the flexure is defined by a pair of gaps machined from a surface of the monolithic structure down to the base.",
    "6. The clamp fixture of claim 5, the flexure comprising a section adjacent to the base configured to bend.",
    "7. The clamp fixture of claim 5, one of the pair of gaps machined to include a non-circular opening configured to receive a non-circular cam shaft.",
    "8. The clamp fixture of claim 1, wherein the one or more rows comprise a plurality of rows.",
    "9. The clamp fixture of claim 1, wherein the monolithic structure is formed of electrically conductive steel.",
    "10. A clamp fixture for clamping a plurality of sliders, comprising: a monolithic structure comprising a row of slider nests for receiving the plurality of sliders, the row comprising: an edge configured to provide a reference datum against which sliders in the row are aligned, a plurality of flexures configured to move between a clamping position where the plurality of flexures clamp the plurality of sliders against the edge, and an open position with a plurality of flexures do not clamp the plurality of sliders against the edge, the plurality of flexures configured to clamp the plurality of sliders independently of each other.",
    "11. The clamp fixture of claim 10, further comprising a cam configured move the plurality of flexures between the clamping position and the open position.",
    "12. The clamp fixture of claim 11, wherein the cam and monolithic structure are configured move the plurality of flexures together between the clamping position and the open position.",
    "13. The clamp fixture of claim 10, the row of slider nests further comprising a pair of sidewalls for each slider nest, the pair of sidewalls configured to guide a slider of the plurality of sliders into the slider nest when the plurality of flexures are in the open position.",
    "14. The clamp fixture of claim 10, the row of slider nests further comprising a pair of pedestals for each slider nest, the pair of pedestals configured to support a slider of the plurality of sliders when the slider is positioned in the slider nest with the plurality of flexures in the open position.",
    "15. A clamp fixture for clamping a plurality of sliders, comprising: a monolithic structure comprising a plurality of slider nests for receiving the plurality of sliders, the plurality of slider nests defined in rows extending in a first direction along the monolithic structure, each row comprising: a plurality of coplanar reference datum edges formed in the monolithic structure, and a plurality of flexures configured to clamp a group of the plurality of sliders against the plurality of reference datum edges, the plurality of flexures configured to clamp the plurality of sliders independently of each other; and one or more cams affixed to the monolithic structure and configured to actuate the plurality of flexures in each row between a clamping position where the plurality of flexures clamp sliders against the plurality of reference datum edges, and an open position where the plurality of flexures do not clamp sliders against the plurality of reference datum edges.",
    "16. The clamp fixture of claim 15, wherein the one or more cams and monolithic structure are configured move the plurality of flexures together between the clamping position and the open position.",
    "17. The clamp fixture of claim 15, the row of slider nests further comprising a pair of sidewalls for each slider nest, the pair of sidewalls configured to guide a slider of the plurality of sliders into the slider nest when the plurality of flexures are in the open position.",
    "18. The clamp fixture of claim 10, the row of slider nests further comprising a pair of pedestals for each slider nest, the pair of pedestals configured to support a slider of the plurality of sliders when the slider is positioned in the slider nest with the plurality of flexures in the open position.",
    "19. A clamp fixture for clamping a plurality of sliders, comprising: alignment means for aligning the plurality of sliders against one or more reference datums; biasing means for clamping each of the plurality of sliders against the alignment means independently of each other; and actuation means for actuating the biasing means between a clamping position where the biasing means clamp each of the sliders together against the alignment means, and an open position where the biasing means do not clamp the sliders against the alignment means."
  ],
  "description_excerpt": "Critical dimension scanning electron microscopes (CD-SEMs) and Dual Beam Focused Ion Beam SEMs (FIB) are often used to analyze and provide measurement of sub-micron features in surface and cross-sections of the read and write heads of a magnetic transducer in magnetic hard disk drives. A group of sliders including read/write heads may be arranged in a fixture called a rowbar holder, and from there, the sliders may be transferred onto an adhesive strip on a wafer for analysis in the CD-SEM and FIB. When testing head sliders in a high throughput automated metrology CD-SEM and FIB tool, it is important to precisely align ends of the sliders including the deposited read and write head film layers along a reference datum. If the high throughput CD-SEM or FIB encounters a misaligned head slider, it may be unable to automatically progress analysis of features of the succeeding slider's read/write layers, requiring stoppage of the metrology test while a technician manually re-teaches position reference in the application software on misaligned sliders and then resumes the automated testing run. High throughput CD-SEMs and FIBs are expensive tools to run, and any unexpected work stoppage to re-teach misaligned sliders can be costly.\n\nA problem with conventional slider testing as explained above is that the dimensions of head sliders can vary slightly due to manufacturing tolerances. Thus, when clamped within a rowbar holder, the deposited end of some sliders may rest properly against the reference datum, but smaller sliders may rotate slightly, or otherwise have deposited ends which are not flush against the reference datum.",
  "cpc": [
    "G01B 15/00",
    "B25B 1/08",
    "B25B 5/08",
    "G11B 5/3166",
    "G11B 5/3173",
    "H05K 7/12"
  ],
  "ipc": [
    "B25B 5/08",
    "G01B 15/00",
    "G11B 5/31",
    "H05K 7/12"
  ],
  "assignees": [
    "SanDisk Technologies LLC"
  ],
  "inventors": [
    "Darrick T. Smith",
    "Glenn P. Gee",
    "Anthony M. Bagus",
    "Teodosio B. Quilapquilap, JR.",
    "Sharon C. Agtina"
  ],
  "filing_date": "2017-12-22",
  "publication_date": "2020-05-19",
  "grant_date": "2020-05-19",
  "priority_date": "2017-12-22",
  "application_number": "US-201715852068-A",
  "family_id": "66950096",
  "cited_by_count": 0,
  "citations": [
    "US3665370A",
    "US3777596A",
    "US3975805A",
    "US4157583A",
    "US4502601A",
    "US6481204B1",
    "CA2470290A1"
  ]
}