Ion Mills — Used Gatan 691 for Semiconductor and Materials Research (Gatan)

How Much Does Used Gatan 691 Cost in 2026?

The used Gatan 691 Ion Mill typically sells in the $15,000 range in 2026, with a consistent price due to stable demand in the semiconductor and materials research sectors. Units in condition grade B, which is typical for this model, will generally fall within this range. Higher-grade units (A or A–) can command up to $18,000, depending on the refurbishment quality and documentation. Refurbishers like Ferrotec and Axus Technology commonly handle these units, offering warranties of 6 to 12 months. Compared to a new Gatan 691, which can cost upwards of $35,000, buying used offers a 40–60% cost savings.

However, it’s important to understand the financial consequences of a poor purchase. A faulty or under-maintained unit can lead to significant downtime—up to 2–3 weeks—during repair, which can cost a lab or semiconductor facility $10,000–$15,000 in lost productivity. Additionally, if the unit fails after purchase, the cost of replacement parts and labor can exceed $5,000. Always verify the unit’s maintenance history and ensure it has been serviced within the last 3–5 years.

Used Gatan 691 Specifications and Compatible Tools

The Gatan 691 is a dual-beam ion mill designed for precision thinning and polishing of samples for transmission electron microscopy (TEM). It typically operates at ion beam energies between 0.5 and 5 keV and can achieve milling rates as low as 10 nm/min for ultra-precise applications. The unit is commonly used in conjunction with electron microscopes from manufacturers like JEOL and Hitachi, particularly models from the 2000–2015 production years.

The typical lifecycle of a Gatan 691 is around 8,000–10,000 RF-hours, depending on usage intensity. Units over 15 years old may require more frequent maintenance. Incompatibility can occur with newer TEM systems that require higher-resolution alignment features not present in the 691. Specifically, the 691 may not align properly with the JEOL JEM-ARM300F due to its lack of a modern alignment port. Failure to address this incompatibility can result in poor sample preparation and up to $8,000 in lost research hours.

What to Check Before Buying a Used Gatan 691 in 2026

1. Verify the production year. Units produced before 2010 may have outdated control systems. A unit manufactured after 2012 is preferable for compatibility with modern software.

2. Check the ion gun condition. The ion gun should show less than 10% erosion on the cathode. A visual inspection or a test run with a sample can reveal wear. If the gun shows more than 15% erosion, reject the unit.

3. Test the vacuum system. Use a leak test with helium to ensure the system reaches and maintains a base pressure of less than 1×10⁻⁵ Torr. A failure to reach this threshold can lead to contamination and sample degradation, costing up to $6,000 in rework.

4. Inspect the control software. Ensure the software version is compatible with your lab’s systems. A mismatch can lead to operational delays and integration costs of $2,000–$4,000.

5. Review the maintenance log. Look for regular servicing every 2–3 years. Units that haven’t been serviced in over 5 years are at high risk of mechanical failure, which can cost $7,000–$10,000 in repairs.

FAQ

Q: How does the Gatan 691 compare to the Gatan 692?
A: The 692 offers a higher beam current and better automation, but the 691 is more cost-effective. The 691 is suitable for most TEM prep tasks, while the 692 is better for high-throughput environments. The 692 typically costs $2,000–$3,000 more used.

Q: Can I install the Gatan 691 in a lab with a 2018 JEOL JEM-2800?
A: Yes, but you may need an adapter for the alignment port. Confirm compatibility with the vendor. Failure to do so can cause misalignment and up to $5,000 in sample loss.

Q: Should I buy a used Gatan 691 if I don’t have a budget for a new one?
A: Yes, but only if the unit has been serviced within the last 3–5 years and has a full maintenance log. A poorly maintained unit can cost $7,000–$10,000 in repairs and downtime.

Q: How long can a used Gatan 691 last with proper maintenance?
A: With regular servicing every 2–3 years, a Gatan 691 can last 10–15 years. Units over 15 years old may require more frequent repairs, which can add up to $3,000–$5,000 annually.

Q: What’s the average cost of a major repair?
A: Major repairs, such as ion gun replacement or vacuum system overhaul, can cost between $4,000 and $8,000. Always factor this into your total cost of ownership.