The SXUV20HS1 (part number ODD-SXU-004) is a high-speed circular photodiode from Opto Diode, a division of ITW, manufactured in Camarillo, California. It combines a Φ5.01 mm (20 mm²) active area with a 3.5 ns maximum rise time at 150 V reverse bias, and it belongs to the SXUV family — Opto Diode’s radiation-hardened process, engineered to hold its response after exposure to EUV and UV conditions. The SXUV category page lists it as a “High Speed EUV Photodetector (1nm-190nm)”. Specifications below are from the controlled datasheet, Revision October 10, 2024.
Electro-optical characteristics at 25 °C
| Parameter | Test conditions | Min | Typ | Max | Units |
|---|---|---|---|---|---|
| Active area | Φ5.01 mm | — | 20 | — | mm² |
| Responsivity | see graph in datasheet — specified as a curve | — | — | — | A/W |
| Reverse breakdown voltage, VR | IR = 1 µA | 160 | — | — | V |
| Capacitance, C | VR = 0 V | — | 500 | 1500 | pF |
| Rise time | RL = 50 Ω, VR = 150 V | — | — | 3.5 | ns |
| Dark current | VR = 150 V | — | — | 100 | nA |
The datasheet prints three curves: a typical photon-responsivity curve plotted from 1 nm to 1000 nm, capacitance versus voltage plotted from 0 to 25 V — falling steeply as bias is applied — and dark current versus voltage plotted from 0 to 160 V.
Built for speed at high reverse bias
The rise-time specification is written at the detector’s working point: 3.5 ns maximum into a 50 Ω load at 150 V reverse bias, with dark current held to 100 nA maximum at that same bias, and a reverse breakdown voltage of 160 V minimum (at IR = 1 µA) providing the headroom for it. The feature list also specifies grid lines of 5 microns at a 100 micron pitch — the fine parallel grid lines are visible across the circular active area in the datasheet’s product photo.
Radiation hardness, and a thermal caution worth reading
Two feature bullets on the SXUV20HS1 datasheet do not appear on the AXUV20HS1’s: “Superior Radiation Hardness” and “High Photon Flux Robustness.” Both sheets carry “Ideal for EUV Detection.” That matches the SXUV family positioning — the process is engineered to hold its response after exposure to EUV and UV conditions, which is why the family serves dose and power monitoring roles, and the family is characterized for detection from 1 nm to 190 nm. The datasheet’s thermal table gives three ratings — ambient –10 to +40 °C, nitrogen or vacuum –20 to +80 °C, and a 260 °C lead-soldering limit (0.080 in from the case, 10 seconds) — and attaches a footnote to the ambient rating specifically: temperatures exceeding it may create oxide growth on the active area, and over time responsivity to low-energy radiation and to wavelengths below 150 nm will be compromised. Stay inside the ambient rating if the deep-UV end of the response matters to your measurement.
SXUV20HS1 vs AXUV20HS1
Opto Diode also makes the AXUV20HS1 — the same Φ5.01 mm, 20 mm² circular geometry, the same 160 V minimum breakdown, and the same 3.5 ns maximum rise time at 150 V. The published electro-optical tables differ in one line — capacitance — and the SXUV datasheet’s feature list adds two bullets the AXUV’s does not carry:
| Parameter | SXUV20HS1 | AXUV20HS1 |
|---|---|---|
| Active area | Φ5.01 mm / 20 mm² | Φ5.01 mm / 20 mm² |
| Rise time (RL = 50 Ω, VR = 150 V) | 3.5 ns max | 3.5 ns max |
| Reverse breakdown (IR = 1 µA) | 160 V min | 160 V min |
| Capacitance (VR = 0 V) | 500 pF typ / 1500 pF max | 300 pF typ / 900 pF max |
| Dark current (VR = 150 V) | 100 nA max | 100 nA max |
| Datasheet feature list | Circular Active Area; Ideal for EUV Detection; High Speed; Grid lines 5 microns, Pitch 100 microns; Protective Cover Plate — plus Superior Radiation Hardness and High Photon Flux Robustness | Circular Active Area; Ideal for EUV Detection; High Speed; Grid Lines 5 Microns, Pitch 100 Microns; Protective Cover Plate |
SXUV20HS1 figures from its datasheet, Revision October 10, 2024; AXUV20HS1 figures from its datasheet, Revision October 17, 2019.
On family selection, Opto Diode’s SXUV100 page puts it directly: SXUV is the radiation-hardened family, engineered to hold its response after exposure to EUV and UV conditions, while AXUV is optimized for windowless broadband response and absolute, calibration-grade measurement. The SXUV20HS1 is available direct from Opto Diode — direct orders are subject to a $3,000 minimum — and the SXUV category page links its Digi-Key listing.
Package and handling
The package drawing shows a flat-pack outline, 0.398 × 0.350 in (10.10 × 8.90 mm), with two Ø0.018 in (0.45 mm) leads — anode (P) at the notch end, cathode (N) opposite. Separately, the feature list specifies a protective cover plate: the part ships with a temporary cover protecting the photodiode and its wire bonds, and the datasheet directs users to review the application note Handling Precautions for AXUV, SXUV, and UVG Detectors Opto Diode also publishes Proper Use of AXUV, SXUV, and UVG Detectors, which adds the operating envelope, an incoming functional check, and correct anode/cathode wiring to avoid photo-emission error. before removing it.
Frequently asked questions
What bias does the SXUV20HS1 need for its rated speed?
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The 3.5 ns maximum rise time is specified into a 50 ohm load at 150 V reverse bias. The datasheet supports that operating point with a 160 V minimum reverse breakdown voltage (at 1 microamp) and a 100 nA maximum dark current at 150 V.
What is the difference between the SXUV20HS1 and the AXUV20HS1?
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The published electro-optical specifications are identical except capacitance: 500 pF typical / 1500 pF maximum for the SXUV20HS1 versus 300 pF typical / 900 pF maximum for the AXUV20HS1, both at zero bias. The real distinction is the process family: SXUV is radiation-hardened to hold its response under EUV and UV exposure, while AXUV is optimized for windowless broadband response and absolute, calibration-grade measurement.
What wavelength range does the SXUV20HS1 cover?
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Opto Diode’s category page lists it as a High Speed EUV Photodetector for 1 nm to 190 nm, the range the SXUV family is characterized for. The datasheet itself gives responsivity as a typical photon-responsivity curve plotted from 1 nm to 1000 nm rather than as a numeric range.
Why does the datasheet warn about temperature and oxide growth?
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A footnote attached to the ambient temperature rating (-10 °C to 40 °C) states that temperatures exceeding it may create oxide growth on the active area, and that over time responsivity to low-energy radiation and wavelengths below 150 nm will be compromised. In short: exceeding the ambient thermal rating can degrade exactly the deep-UV response the detector is bought for.
Specifying a high-speed EUV detector, or deciding between the SXUV and AXUV versions? Opto Diode typically responds to online requests within 1–2 business days.
Reviewed and updated August 2026.