ULTRA and ULTRA-AS Ion Implanted Silicon Charged Particle Radiation Detectors

Silicon Charged Particle Radiation DetectorsULTRA
  • The standard for charged-particle detector spectroscopy.
  • Ultra-thin entrance contact for optimum energy resolution.
  • High geometric efficiency due to close detector-to-can spacing.
  • Rugged and reliable.
  • Gold-plated cans for contacts that last a lifetime.
  • Advanced surface passivation for total device stability.
  • ORTEC quality and reliability.
  • Bakeable up to 200°C (requires special order).

ULTRA-AS
  • Low-background version for alpha spectroscopy.
  • Literature +

  • More Information +


    ULTRA ion-implanted-silicon detectors for alpha and beta spectroscopy are the most advanced charged-particle detectors ever produced. They possess the reliability that has made ORTEC the sole supplier to NASA of silicon detectors for space applications.

    Both the entrance and the back contact are ion implanted. The entrance contact is an extremely thin (∼500 Å) boron implantation. The distance between the silicon surface and the top of the mounting can is <1 mm providing maximum geometric efficiency. The front contact can be easily cleaned with a solvent-moistened cotton swab.

    ULTRA detectors have gold-plated mounting cans. The superior electrical conductivity of gold, which can never oxidize, makes it the choice versus stainless steel or aluminum. An advanced surface passivation that covers the critical silicon dioxide layer guarantees absolute device stability.

    The extremely low leakage current permits specifying the energy resolution at 1-µs amplifier shaping time constant.

    Low-background ULTRA-AS detectors are made with special low-background materials and have an optimized depletion thickness to minimize background counts from cosmic rays. All ORTEC Alpha Spectrometers (Alpha Aria, Alpha Duo, and Alpha Ensemble) can be equipped with either ULTRA-AS detectors or R-Series, Ruggedized Surface Barrier Detectors. All these spectrometers, when equipped with a 450 mm2 detector, have a warranted background performance of ≤24 counts per day, over the 3- to 8-MeV energy range.

    The dimensions of the ULTRA and ULTRA-AS detector mounting cans being identical to those of the corresponding size A or R Series detectors ensure that ULTRA detectors will fit perfectly in any application where A or R Series detectors are being used now.

    *Extensive care regarding detector and chamber cleanliness can result in background count levels as low as 0.05 counts/hr/cm2 of active area, corresponding to 6 counts/24 hours, for a 450 mm2 active area.

    **ULTRA Series detectors require positive bias voltage. R Series detectors require negative polarity bias.
  • Mounting Arrangements +


    B  Microdot connector on the rear of the can.

    C  BNC connector on the rear of the can.

    T  Microdot on the side of the can. Only one side of the can has an opening. Available up to 600 mm2 active area.

    Dimensions given in millimeters.


    Detector Size (mm2)

    W (Nominal)
    Type B Rear Microdot Type C Rear BNC Type "BLIND" T Side Microdot 
     X Y Z X Y Z X Y Z
     025  5.6 16.7 12.3 7.1 16.7 12.3 15.9 19.4 7.9 9.9
     050  8.0 16.7 12.3 7.1 16.7 12.3 15.9 19.4 7.9 9.9
     100  11.3 23.6 12.3 7.1 23.6 12.3 15.9 26.1 7.9 9.9
     150  13.8 23.6 12.3 7.1 23.6 12.3 15.9 26.1 7.9 9.9
     300  19.5 28.6 12.3 7.1 28.6 12.3 15.9 31.6 7.9 9.9
     450 23.9 32.0 12.3
    7.1 32.0 12.3
    15.9 34.8 7.9 9.9
     490 25.0 33.4 12.3
    7.1
    33.4 12.3
    15.9      
     600 27.6 36.1 12.3
    7.1
    36.1 12.3
    15.9 38.4 7.9 9.9
     900 33.9 45.2 12.3
    7.1
    45.2 12.3
    15.9      
     1200 40.0 48.8 12.3
    7.1
    48.8 12.3
    15.9      
     2000 51.0 65.5 12.3
    7.1
    65.5 12.3
    15.9      
     3000 62.0 76.2 12.3
    7.1
    76.2 12.3
    15.9      
     Tolerance ±0.5 ±0.3
    ±0.3
    ±0.3
    ±0.3
    ±0.3
    ±0.3
    ±0.3
    ±0.3
    ±0.3
  • Ordering Information for ULTRA Detectors +


    Specify B, C, or "Blind" T** Mount. To Order: Add the appropriate letter prefix for the mounting desired. Example: BU-016-300-100 or TU-016-300-100.

    * First three digits of Model No. indicate total system resolution FWHM for 241Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

    ** “Blind” T Mount available up to 600-mm2 ULTRAs.


    Active Area (mm2)
    Guaranteed Maximum Resolution* (keV FWHM) Minimum Depletion Depth 100 µm
    α β Model No.
    25 12
    14
    6
    8
    U-012-025-100
    U-014-025-100
    50 12
    14
    6
    8
    U-012-050-100
    U-014-050-100
    100 13
    15
    7
    9
    U-013-100-100
    U-015-100-100
    150 14
    16
    9
    10
    U-014-150-100
    U-016-150-100
    300 16
    19
    11
    14
    U-016-300-100
    U-019-300-100
    450 17
    21
    12
    16
    U-017-450-100
    U-021-450-100
    600 22
    24
    17
    19
    U-022-600-100
    U-024-600-100
    900 27
    33
    22
    28
    U-027-600-100
    U-033-900-100
    1200 35
    42
    30
    37
    U-035-1200-100
    U-042-1200-100
    2000 50
    58
    45
    53
    U-050-2000-100
    U-058-2000-100
    3000 60
    70
    55
    65
    U-060-3000-100
    U-070-3000-100


    Active Area (mm2)
    Guaranteed Maximum Resolution* (keV FWHM) Minimum Depletion Depth 300 µm
    α β Model No.
    25 11
    13
    5
    7
    U-011-025-300
    U-013-025-300
    50 11
    13
    5
    7
    U-011-050-300
    U-013-050-300
    100 12
    14
    6
    8
    U-012-100-300
    U-014-100-300
    150 13
    15
    8
    9
    U-013-150-300
    U-015-150-300
    300 15
    18
    10
    13
    U-015-300-300
    U-018-300-300
    450 16
    20
    11
    15
    U-016-450-300
    U-020-450-300
    600 21
    23
    16
    18
    U-021-600-300
    U-023-600-300
    900 25
    30
    20
    25
    U-025-900-300
    U-030-900-300
    1200 30
    37
    25
    32
    U-030-1200-300
    U-037-1200-300
    2000 40
    48
    35
    43
    U-040-2000-300
    U-048-2000-300
    3000 55
    65
    50
    60
    U-055-3000-300
    U-065-3000-300


    Active Area (mm2)
    Guaranteed Maximum Resolution* (keV FWHM) Minimum Depletion Depth 500 µm
    α β Model No.
    25 11
    12
    5
    6
    U-011-025-500
    U-012-025-500
    50 11
    13
    5
    7
    U-011-050-500
    U-013-050-500
    100 12
    14
    6
    8
    U-012-100-500
    U-014-100-500
    150 12
    14
    7
    9
    U-012-150-500
    U-014-150-500
    300 14
    17
    9
    12
    U-014-300-500
    U-017-300-500
    450 15
    19
    10
    14
    U-015-450-500
    U-019-450-500
    600 20
    22
    15
    17
    U-020-600-500
    U-022-600-500
    900 23
    28
    18
    23
    U-023-900-500
    U-028-900-500
    1200 28
    38
    23
    30
    U-028-1200-500
    U-035-1200-500
    2000 35
    43
    30
    38
    U-035-2000-500
    U-043-2000-500
    3000 50
    60
    45
    55
    U-050-3000-500
    U-060-3000-500
  • Ordering Information for ULTRA-AS Detectors +


    Specify B, C, or "Blind" T** Mount. To Order: Add the appropriate letter prefix for the mounting desired. Example: BU-034-1200-AS or TU-019-300-AS.**

    * First three digits of Model No. indicate total system resolution FWHM for 241Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

    ** “Blind” T Mount available up to 600-mm2 ULTRA-AS.

    ~100 µm active depth to minimize cosmic background.

    Active Area (mm2)
    Alpha Resolution* (keV FWHM @ 5.486 MeV) Model No.
    300 19 U-019-300-AS
    450 20 U-020-450-AS
    490 20 U-020-490-AS
    600 24 U-024-600-AS
    900 29 U-029-900-AS
    1200 37 U-037-1200-AS
    2000 53 U-053-2000-AS
    3000 64 U-064-3000-AS
  • Ordering Information for ULTRA-AS ENS Detectors +


    ULTRA-AS to be installed and system tested with an Alpha Suite Spectrometer.

    Supplied in B Mount.

    * First three digits of Model No. indicate total system resolution FWHM for 241Am, 5.486-MeV alphas, using standard ORTEC electronics and 1-µs shaping time constants.

    ~100 µm active depth to minimize cosmic background.

    Active Area (mm2)
    Alpha Resolution* (keV FWHM @ 5.486 MeV) Model No.
    300 19 ENS-U300
    450 20 ENS-U450
    490 20 ENS-U490
    600 24 ENS-U600
    900 29 ENS-U900
    1200 37 ENS-U1200
    2000 53 ENS-U2000
    3000 64 ENS-U3000