The FAST SDD® represents Amptek’s highest performance silicon drift detector (SDD), capable of count rates over 1,000,000 CPS (counts per second) while maintaining excellent resolution. The resolution is the same as the standard SDD (125 eV FWHM at the Mn Ka line), and the typical peak-to-background ratio of 20,000:1 is the same, but at a much higher count rate. The FAST SDD® is also available with our C-Series low energy windows for soft x-ray analysis.
Unlike our conventional SDDs which use a junction gate field-effect transistor (JFET) inside the hermetically sealed TO-8 package, along with an external preamplifier, the FAST SDD uses a complementary metal-oxide-semiconductor (CMOS) preamplifier inside the TO-8 package, and replaces the JFET with a metal-oxide-semiconductor field-effect transistor (MOSFET). This significantly reduces capacitance, providing much lower series noise and yielding improved resolution at very short peaking times. The FAST SDD® uses the same detector but with a preamplifier giving lower noise at short peaking times. Improved (lower) resolution enables isolation/separation of fluorescent X-rays with close energy values where peaks would otherwise overlap, permitting users better identification all of the elements in their sample(s). Short peaking times also yield significant improvements in count rates; more counts provide better statistics.
|The XR-100FAST SDD with the PX5||The FAST SDD® with its preamplifier is available in several OEM configurations||The X-123FAST SDD configuration includes the detector, preamplifier, digital processor and power supplies all in one box|
The FAST SDD® is available in all three standard Amptek packages, permitting you to select the version best-suited to your requirements
|125 eV FWHM||4 µs|
|130 eV FWHM||1 µs|
|140 eV FWHM||0.2 µs|
|160 eV FWHM||0.05 µs|
Table 1. Resolution vs. Peaking Time for the FAST SDD®.
Figure 1. Resolution vs. peaking time for the FAST SDD® and standard SDD.
Figure 2. Energy Resolution and Count Rate: This plot shows how the energy resolution at 5.9 keV is related to the output count rate for Amptek’s X-ray detectors, as a function of the pulse shaping time and the equivalent peaking time in a digital processor. These are typical values at full cooling (220K). For example, at a Tpeak of 9.6 microseconds (equivalent to 4.0 microsecond pulse shaping time) the output count rate at 50% dead time is 18 kcps. This is a function only of the pulse processing so is the same for all detectors. The energy resolution for a 6 mm2 Si-PIN is just under 160 eV FWHM while for a 25 mm2 SDD it is 130 eV FWHM.
Figure 3. Throughput for the FAST SDD®.
Figure 4. Resolution vs. Input Counts Rate (ICR) for Various Peaking Times for FAST SDD.
In the bottom plot, the black curve represents “Fano broadening”, the theoretical limit with a Si based detectors, arising from quantum fluctuations in the charge production process. The colored curves represent the combination of Fano broadening and intrinsic electronic noise under optimum conditions (full cooling and long peaking time). The detector selection is most important at the lowest energies because Fano broadening dominates at high enough energies.
In the top plot, the efficiency at low energies is determined by transmission through the window and detector dead layer. The efficiency at high energies is determined by attenuation in the active depth of the detector. A Si detector with Be window is recommended between about 2 and 30 keV. A Si detector with a C1 or C2 window is recommended at lower energies, while a CdTe detector is best at energies above 30 keV.
Efficiency Package: A ZIP file of coefficients and a FAQ about efficiency. This pacakge is provided for general information. It should not be used as a basis for critical quantitative analysis.
|Detector Type||Silicon Drift Detector (SDD) with CMOS preamplifier|
|Detector Size||25 mm2|
|Silicon Thickness||500 µm, See efficiency curves|
|Collimator||Internal MultiLayer Collimator (ML)|
|Energy Resolution @ 5.9 keV (55Fe)||125 - 140 eV FWHM depending on peaking time|
|Peak to Background||20,000:1 (ratio of counts from 5.9 keV to 1 keV) (typical)|
|Detector Window Options||Beryllium (Be): 0.5 mil (12.5 µm) or 0.3 mil (8 µm)
C Series Low energy windows
|Charge Sensitive Preamplifier||Amptek custom reset preamplifier|
|Gain Stability||<20 ppm/°C (typical)|
|XR-100FastSDD Case Size||3.00 x 1.75 x 1.13 in (7.6 x 4.4 x 2.9 cm)|
|XR-100FastSDD Weight||4.4 ounces (125 g)|
|Total Power||<2 Watt|
|Warranty Period||1 Year|
|Typical Device Lifetime||5 to 10 years, depending on use|
|Operation conditions||0°C to +50°C|
|Storage and Shipping||Long term storage: 10+ years in dry environment
Typical Storage and Shipping: -20°C to +50°C, 10 to 90% humidity non condensing
Certificate #: CU 72072412 02
Tested to: UL 61010-1: 2004 R7 .05
CAN/CSA-C22.2 61010-1: 2004
|Preamp Power||±8 to 9 V @ 15 mA with no more than 50 mV peak-to-peak noise|
|Detector Power||-70 to -200 V @ 25 µA very stable <0.1% variation|
|Cooler Power||Current = 450 mA maximum, voltage = 3.5 V maximum with <100 mV peak-to-peak noise
Note: the XR-100SDD includes its own temperature controller
|Preamplifier Sensitivity||4 mV/keV typical (may vary for different detectors)|
|Preamplifier Polarity||Positive signal output (1 kohm maximum load)|
|Temperature Monitor Sensitivity||PX5: direct reading in Kelvin through software|
|X-123FastSDD||The silicon drift detector (FastSDD) is also available in the X-123SDD Silicon Drift Detector System configuration. The X-123SDD configuration includes the detector, preamplifier, DP5 digital pulse processor and MCA, and the PC5 power supply. All that is needed is a +5 Volts DC input and a USB, RS232, or Ethernet connection to your computer.|
|Vacuum Accessories||The FastSDD is compatible with all Amptek vacuum accessories|
|OEM||The FastSDD is compatible with all Amptek OEM configurations|
Figure 6. Stainless Steel 316 Spectrum taken in 1 second with the FAST SDD.
The below table displays the quantitative analysis of the data in figure 4. This spectrum was taken in 1 second with the FAST SDD®.
|Element||Certified Concentration||Fast SDD® Result in 1 second|
|V||0.05||0.16 ± 0.28|
|Cr||18.45||18.32 ± 0.80|
|Mn||1.63||0.40 ± 0.55|
|Fe||64.51||65.89 ± 1.64|
|Co||0.10||0.00 ± 0.40|
|Ni||12.18||12.56 ± 0.47|
|Cu||0.17||0.19 ± 0.02|
|Mo||2.38||2.34 ± 0.08|
Figure 8. Solder spectrum taken in 1 second (1 µs peaking time) with the FAST SDD.
All results on this page are typical performance values at full cooling; please Contact Us to discuss guaranteed performance under different operating conditions. Specifications subject to change without notice.