Arc Evaporated Carbon Foils - The Workhorse!
For accelerator users worldwide!
Arc evaporated carbon foils come both on glass substrates, hand polished with parting agent to permit removal by floating (0.1 to 180µg/sq.cm), and free-standing (181 to 2000µg/sq.cm) provided in individual protective containers.
ACF has two standard sizes on glass substrates, 25mm X 70mm and 50mm X 70mm.
The free-standing foils' dimensions are nominally 24mm X 68mm and 48mm X 68mm.
Additionally, we provide foils in a wide variety of custom shapes and sizes, as well as on different mounting options.
Areal Density: Standard foils are regularly available from stock. They are categorized by their areal density, with minimal variation (+/- 10% or +/- 0.2µg/sq.cm for the thinnest foils). Tighter tolerances are available by quote. The areal density of our foils, also known as surface density, specific density, or mass per unit area, is in units of micrograms per square centimeter. Foils are measured optically and/or by weighing in order to maximize accuracy. Please see the ACF-Metals' "Product Information" for more properties of these foils, especially for information regarding flatness, smoothness, and light-tightness.
Foil Purity: By using high-purity materials, we take particular care to manufacture foils from the safest isotopic mixture, almost entirely carbon-12 with 1.1% of carbon-13. ACF-Metals does not produce hybrid carbon foils (ie. boron) which introduce extra problems for radiation safety in laboratories. See our Product Information on how some hybrid carbon foils have serious risks associated with their use.
Collodion Option: Foils below 5.0µg/sq.cm may be difficult to mount over apertures larger than a few mm in diameter. When requested, ACF-Metals will add an additional coating of collodion on one side of the carbon foil. This provides additional support for the foil, and for some users, a longer foil lifetime.
Light Tightness: In order to minimize issues associated with naturally occurring pinholes, some investigators will use multiple layers of carbon foils. Light tightness may be particularly important when foils are used as optical filters, neutralizer foils, and windows for low-pressure gas-cell targets. ACF-Metals offers layered carbon foils in certain thicknesses. Note: Pinholes are observed to form spontaneously in hybrid type boron-carbon foils at temperatures above 1800 K, another reason why ACF-Metals does not offer hybrid foils.
Additional Savings: Quantity discounts are available on single shipments of carbon foils of the same size and areal density: 10% (quantity of 100+) or 12% (quantity of 1000+). Please contact ACF-Metals directly to place orders that would involve this discount.
Please request a FREE COPY of our PRODUCT INFORMATION, for elaboration on the above highlights and for additional helpful information!
Carbon foils made by ACF-Metals are used in nuclear, space physics, time-of-flight, optical, chemical, medical, and microscopy fields. Our foils are the most common stripper foils (charge-changing foils) and target supporting foils used in radio-pharmaceutical manufacturing applications and research involving particle accelerators.
Our in-house technical team, led by physicist
Dr. John Stoner, is prepared to answer questions and provide ideas and feedback regarding your application.
Dr. Stoner reads each email and is available to discuss techniques, tolerances, and troubleshooting.