The AXUV20HS1 is a high-speed circular silicon photodiode from Opto Diode, a division of ITW, in Camarillo, California. It pairs a Φ5 mm (20 mm²) active area with a 3.5 ns maximum rise time for fast detection of low-energy electrons and soft x-rays. It is the smallest-area high-speed circular photodiode in Opto Diode’s current AXUV catalog; if you are looking for the AXUVHS5, which Opto Diode no longer lists, compare the two parts below before substituting.
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 | — | 300 | 900 | pF |
| Rise time | RL = 50 Ω, VR = 150 V | — | — | 3.5 | ns |
| Dark current | VR = 150 V | — | — | 100 | nA |
Datasheet: AXUV20HS1 datasheet (PDF), Revision October 17, 2019 — includes the responsivity curves, package drawing and dimensions.
Temperature ratings
| Storage & operating range | Rating |
|---|---|
| Ambient | −10 °C to 40 °C |
| Nitrogen or vacuum | −20 °C to 80 °C |
| Lead soldering temperature | 260 °C (0.080″ from case, 10 seconds) |
Temperatures exceeding the ambient rating can create oxide growth on the active area; over time, responsivity to low-energy radiation and to wavelengths below 150 nm will be compromised.
Handling note: the AXUV20HS1 ships with a temporary cover plate protecting the photodiode chip and its wire bonds. Review the application note Handling Precautions for AXUV, SXUV, and UVG Detectors before removing the cover.
Key features
- Circular active area — Φ5 mm (20 mm² typical)
- High speed — 3.5 ns maximum rise time
- Electron detection to 200 eV
- Ideal for EUV detection
- Grid lines 5 microns, pitch 100 microns
- Supplied with a protective cover plate
Where the AXUV20HS1 is used
The AXUV20HS1 is built for high-speed detection of low-energy electrons or x-rays. Like all AXUV detectors, it uses a windowless silicon design that measures photons, electrons, or x-rays from 0.0124 nm to 190 nm and detects energy from 100 eV to 50 keV, with 100% internal quantum efficiency. The AXUV family serves electron detection, synchrotron radiation monitoring, and electron reticle inspection; the HS1’s nanosecond-class rise time suits it to fast, pulsed measurements within those applications.
Replacing the AXUVHS5
The AXUVHS5 no longer appears in Opto Diode’s current product catalog or product listings, and the AXUV20HS1 is a current high-speed circular AXUV photodiode that customers evaluate in its place. Opto Diode publishes no cross-reference or equivalence between the two, and they are not interchangeable — compare before designing in:
| Parameter | AXUV20HS1 (current) | AXUVHS5 (no longer listed) |
|---|---|---|
| Active area | Φ5 mm circular, 20 mm² | 1 mm × 1 mm, 1 mm² |
| Rise time | 3.5 ns max (RL = 50 Ω, VR = 150 V) | 700 ps max (RL = 50 Ω, VR = 52 V) |
| Capacitance (VR = 0 V) | 300 pF typ / 900 pF max | 15 pF typ / 50 pF max |
| Reverse breakdown, min | 160 V | 55 V |
| Dark current | 100 nA max (VR = 150 V) | 1 nA typ / 10 nA max (VR = 52 V) |
| Connection | Package with protective cover plate (see datasheet drawing) | SMA connector |
The AXUV20HS1 offers twenty times the collection area; the AXUVHS5 was faster and lower-capacitance in a smaller, SMA-connectorized format. The two parts are specified at different reverse bias — 150 V for the AXUV20HS1, 52 V for the AXUVHS5 — so the rise-time and dark-current figures are not same-condition comparisons; capacitance is quoted at VR = 0 V for both. If your design needs the AXUVHS5’s sub-nanosecond speed or its form factor, talk to our applications engineers about current options before committing to a substitution; Opto Diode also lists the AXUV63HS1 and the center-hole AXUV63HS1-CH (both 63 mm²) as current high-speed circular parts. AXUVHS5 specifications above are from its last published datasheet (Revision November 26, 2019) and are provided for reference only.
Related AXUV detectors
Request a quote or check availability
The AXUV20HS1 (Opto Diode part number ODD-AXU-036) is available direct from Opto Diode and is also listed by Digi-Key. Standard response to an online request is within 1–2 business days; direct orders must meet a $3,000 minimum.
Frequently Asked Questions
What is the active area of the AXUV20HS1?
A circular active area 5.01 mm in diameter, giving a typical area of 20 mm².
How fast is the AXUV20HS1?
Maximum rise time is 3.5 nanoseconds, measured with a 50 Ω load at 150 V reverse bias.
Is the AXUV20HS1 a replacement for the AXUVHS5?
The AXUVHS5 no longer appears in Opto Diode’s current catalog, and the AXUV20HS1 is a current high-speed circular AXUV photodiode that customers evaluate in its place. They differ: the AXUV20HS1 has a much larger 20 mm² active area with a 3.5 ns maximum rise time, while the AXUVHS5 was a 1 mm², SMA-connectorized device with a 700 ps maximum rise time at 52 V reverse bias. Review both datasheets or contact Opto Diode before substituting.
How do I buy the AXUV20HS1?
Contact Opto Diode directly for a quote — the standard response time for an online request is within 1–2 business days. Direct orders are subject to a $3,000 order minimum; the part is also listed by Digi-Key. Opto Diode’s part number is ODD-AXU-036.
Specifications from the AXUV20HS1 datasheet, Revision October 17, 2019. Reviewed and updated July 2026.