Used RTP Equipment Buying Guide: AG Associates Heatpulse, AMAT Radiance & Mattson

This guide is for: a process engineer or fab manager evaluating used RTP tools for anneal, oxidation, or silicide formation—and trying to avoid buying a very expensive paperweight.

I inspected an AG Associates Heatpulse 8108 last month that looked pristine. Clean chamber, recent lamp replacement, all the manuals. Then I checked the pyrometer calibration against a NIST traceable source. It was reading 85°C high at 1000°C. The previous owner had been running their spike anneal at the wrong temperature for two years. Their junction depths were off, their sheet resistance was inconsistent, and they never knew why. Temperature accuracy is everything in RTP. Get it wrong and you don't just have bad process—you have undetected bad process.

A bad RTP purchase costs you $80,000-200,000 for the tool, $20,000-40,000 for installation, and months of process development if the temperature control is off. I've seen RTP tools destroy entire wafer lots because the pyrometer was reading low.

AG Associates Heatpulse: The Classic (And Its Quirks)

The AG Associates Heatpulse 4100/5100/6100 series are the most common used RTP tools. They're lamp-based systems with single-wafer processing and pyrometric temperature control. Prices range from $35,000 for a rough 4100 to $120,000 for a clean 6100 with recent lamp replacement.

The 4100 is the oldest—1980s vintage. It works for basic anneals but lacks modern temperature uniformity control. The 5100 added zone heating for better uniformity. The 6100 is the most capable with closed-loop temperature control and better software.

Critical check: lamp aging. The tungsten-halogen lamps degrade over time. A full lamp set costs $8,000-15,000. Ask for lamp hours. Over 2,000 hours and you're due for replacement soon.

The pyrometer is the other failure point. AG Associates used different pyrometers over the years—some IR, some optical. Calibration drifts. Budget $5,000-10,000 for pyrometer calibration or replacement.

Applied Materials Radiance: The Production Choice

AMAT Radiance RTP systems are found in production fabs worldwide. The Radiance Plus and Radiance RTP are 300mm capable with excellent temperature uniformity. Used prices run $150,000-400,000 depending on configuration and vintage.

The Radiance uses a different approach than AG Associates—closed-loop lamp control with multiple temperature sensors. It's more sophisticated and more expensive to fix when it breaks.

Common issues: lamp power supplies ($12,000-20,000 each, multiple per tool), quartz window degradation ($3,000-8,000 replacement), and gas panel valve failures. The Horiba SEC-7340 MFC is a common gas flow controller on Radiance systems—check calibration.

The chamber is another wear item. The quartz isolation tube cracks with thermal cycling. A replacement is $6,000-12,000 plus labor. Inspect carefully for cracks and clouding.

Mattson Technology: The Dark Horse

Mattson RTP systems (HTA, Paradigm, Aspen) don't get the attention AMAT tools do, but they're capable. The HTA is a batch RTP system—unusual in a market dominated by single-wafer tools.

Used Mattson prices are lower—$60,000-150,000 for an HTA or Paradigm. Parts availability is the concern. Mattson has been through bankruptcy and restructuring. Some components are hard to source.

For a research lab with technical staff, a Mattson can be a bargain. For a production fab needing guaranteed uptime, the parts risk is real.

Temperature Uniformity: The Make-or-Break Spec

RTP lives or dies on temperature uniformity across the wafer. A good tool holds ±3°C at 1000°C. A bad tool might vary ±15°C, creating sheet resistance variation that kills your devices.

Ask for uniformity test data. The seller should have recent maps showing temperature across the wafer at multiple setpoints. If they don't have this data, assume the tool needs work.

Check the edge exclusion. Some older tools have poor edge control—temperature drops 20-30°C at the wafer edge. For devices that use the full wafer, this is a problem.

Pyrometer Calibration: Trust But Verify

The pyrometer measures wafer temperature without contact. It's sensitive to emissivity changes, window coating, and its own calibration drift.

Bring a thermocouple wafer or NIST traceable source to verify. I've seen pyrometers off by 50°C or more. At spike anneal temperatures (1050-1100°C), that error changes junction depth by 20%.

Some tools use multiple pyrometers for zone control. Check that they agree. A 10°C difference between center and edge pyrometers indicates a problem.

Lamp Systems: The Maintenance Reality

Lamp-based RTP tools need regular lamp replacement. Tungsten-halogen lamps last 1,500-3,000 hours depending on operating temperature. Higher temperature processes burn lamps faster.

Ask for lamp replacement records. A tool with original lamps from 2015 is due for $10,000-15,000 in lamp costs soon. Factor this into your offer.

Check the lamp power supply stability. Flickering lamps create temperature oscillations. A power supply rebuild costs $5,000-12,000.

Process Gas and Vacuum Systems

RTP tools use nitrogen, argon, oxygen, or forming gas depending on the process. The gas panel needs clean, calibrated mass flow controllers.

A failing MFC creates process variation. Horiba SEC-Z512MGX units are common on RTP systems—budget $2,000-4,000 for replacement if calibration fails.

The vacuum system matters for purge quality. A small scroll pump maintains the nitrogen purge. Check pump performance—roughing pump failure contaminates the chamber.

What to Do Next

1. Verify pyrometer calibration with a traceable temperature source
2. Request recent temperature uniformity maps at your process temperatures
3. Check lamp hours and budget for replacement if over 2,000 hours
4. Inspect quartz chamber components for cracks or clouding
5. Test gas flow controllers for accuracy and repeatability

RTP seems simple—heat the wafer fast, hold it, cool it down. The complexity is in controlling that temperature precisely across hundreds of wafers per day. Buy capability, not just hardware.

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Related reading: Flat Zone Furnace vs Tube Furnace Buying Guide | Used Oxidation Diffusion Furnace Buying Guide | Used Epitaxy Equipment Buying Guide

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Last updated: May 2026. Information on semiconductor equipment availability and pricing reflects current secondary market conditions.

Page last reviewed May 2026. Pricing and availability reflect current 2026 secondary market conditions.