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    • SiC for RF Devices
    SiC Materials

    Silicon Carbide for RF Devices

    • HPSI Substrate
    • GaN Epitaxy
    • HPSI Substrate
    • GaN Epitaxy

    Proven Expertise in SiC & GaN Materials for RF Applications

    With more than 30 years of development and manufacturing experience, Wolfspeed is driving innovation with the industry’s broadest range of silicon carbide (SiC) and gallium nitride (GaN) materials. Delivering semi-insulating substrates and nitride epitaxy options up to the newly available diameter of 150mm, Wolfspeed materials enable performance far exceeding that of any other technology, for telecom, aerospace, or defense applications with world-leading bandwidth, efficiency and frequency of operation.

    When you partner with Wolfspeed, you get the best and most innovative materials.

    Support

    HPSI SiC Substrates and GaN Epitaxy One Pager (PDF, 522 KB)Download
    Materials Catalog (PDF, 350 KB)Download

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    Infographic diagram of how to order Wolfspeed's materials parts.

    High Purity Semi-Insulating (HPSI) SiC Substrates Product Descriptions

    The Materials Business Unit produces a wide assortment of n-type conductive SiC products. Wolfspeed's industry-leading, high-volume platform process provides our customers with the highest degree of material quality, supply assurance and economies of scale.

    Part Number
    Description
    W4TRF0R-0200
    4H-SiC, HPSI, Research Grade, 100mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ 32.5mm Flat, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
    W4TPF0R-0200
    4H-SiC, HPSI, Production Grade, 100mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ 32.5mm Flat, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
    W4TRG0R-N-0200
    4H-SiC, HPSI, Research Grade, 150mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ Notch, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate
    W4TPG0R-N-0200
    4H-SiC, HPSI, Production Grade, 150mm, On-Axis, ≥1E6 Ω-cm, Standard MPD, 500µm Thick w/ Notch, Double-Sided Polish Si Face CMP Epi Ready, Bare Substrate

    Wolfspeed’s High Purity Semi-Insulating wafers are not vanadium-doped

    Dimensional Properties, Terminology and Measurements

    Flat Length
    Linear dimension of the flat measured with automated optical micrometer.​
    Primary Flat
    The flat of the longest length on the wafer, oriented such that the chord is parallel with a specified low-index crystal plane. Not applicable to 150mm wafers.
    Primary Flat Orientation
    The primary flat is the (1100) plane with the flat face parallel to the [1120] direction.
    Secondary Flat
    A flat of shorter length than the primary flat, whose position with respect to the primary flat identifies the face of the wafer. Not applicable to 150mm wafers.
    Secondary Flat Orientation
    The secondary flat is 90˚ clockwise from the primary flat, +/-5˚, referencing the silicon face up.
    100 mm HPSI Marking
    HPSI products are silicon face polished, and the carbon face of each individual wafer is laser-marked with OCR-compatible font, similar to definitions and characteristics in SEMI T5 specifications. For 100mm wafers, the laser markings are centered when the primary flat is oriented down.
    150 mm HPSI Marking
    HPSI products are silicon face polished, and the carbon face of each individual wafer is laser-marked with OCR-compatible font, similar to definitions and characteristics in SEMI M12. The laser markings are offset right when looking at the carbon face with the notch oriented down.

    GaN Epitaxy Product Descriptions

    Wolfspeed produces GaN, AlxGa1-xN and Al1-yInyN epitaxial layers on SiC substrates. Unless noted otherwise on the product quotation, the epitaxial layer structure will meet or exceed the following specifications (1). Contact Wolfspeed Materials Sales for specification on custom epitaxy requests. Additional comments, terms and conditions may be found in the specification document.

    GaN Epitaxial Layer Specifications – Structural

    Property
    Value or Range
    Precision
    Measurement
    Technique
    Substrate
    On-axis SiC (Semi-Insulating)
    -
    -
    Composition (2)
    AlxGa1-xN or Al1-yInyN
    0 ≤ x ≤ 0.3, 0 ≤ y ≤ 0.2, certain restrictions apply
    Δ x = ± 0.015
    Δ y = ± 0.02
    XRD peak splitting
    Thickness (3)
    1.0 μm to 3.0 μm GaN
    0.5 nm to 1.0 μm AlN
    1.0 nm to 1.0 μm AlxGa1-xN
    1.0 nm to 1.0 μm Al1-yInyN
    2.0 nm to 5.0 nm GaN (Cap Layer)
    5.0 nm to 100 nm SiN (Cap Layer)
    Average
    thickness within
    ± 15% of target
    thickness and
    uniformity
    <10%. (4)
    X-ray or white light
    interferometry
    GaN Crystallinity
    < 250 arcsec (3 μm layer on SiC substrate)
    -
    XRD (0006) FWHM
    (center point)
    Al0.25Ga0.75N
    < 500 arcsec (3 μm layer on SiC substrate)
    -
    XRD (0006) FWHM
    (center point) (5)
    Visible Defects
    < 50/cm2
    -
    Differential
    interference
    microscopy at 50x
    in cross pattern
    with 5 mm edge
    exclusion

    GaN Epitaxial Layer Specifications – Electrical

    Property
    Value or Range
    Precision
    Measurement
    Technique
    Dopant type
    n-type (Si)
    HEMT buffer (Fe and/or C)
    -
    -
    Carrier concentration
    (unintentionally doped)
    < 1E16/cm3, n-type
    -
    CV
    Carrier concentration
    (n-type, Si doped)
    1E16 to 2E19/cm3
    ± 50%
    CV (wafer center,
    room temperature)
    Carrier concentration
    of HEMT structure
    >8E12/cm2
    (25 nm Al0.25Ga0.75N)
    -
    Contactless
    non-destructive
    carrier concentration
    Mobility of HEMT structure
    μ ≥ 1500 cm2 V-1 s-1
    (25 nm Al0.25Ga0.75N)
    -
    Contactless
    non-destructive
    mobility
    Sheet resistivity
    < 2% uniformity
    -
    Contactless
    non-destructive
    sheet resistivity

    Notes:

    1. Certain additional restrictions may apply and will be presented on the product quotation.
    2. Quaternary compositions available upon special request.
    3. Range given for undoped layers. Maximum achievable thickness for doped layers or heterostructures will be reduced.
    4. Precision specification applies only to layers ≥ 0.01 μm thick. Uniformity = (100 x standard deviation / mean). Edge Exclusion is applied.
    5. Please specify epitaxy structure details upon submission of RFQ (i.e. thickness, doping, composition, for each layer).
    6. Custom structures available. Contact Wolfspeed Materials Sales for more information on custom epitaxy requests.

    Tools & Support

    HPSI and Nitride Epitaxy Line Card
    Materials Catalog (PDF, 350 KB)
    Materials Document Library
    Contact the Materials Team

    Knowledge Center

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