On the lithography floor, photoresist bake isn’t a nice-to-have—it’s the line in the sand between making yield and watching scrap pile up. A 2°C drift during soft bake is enough to spread CD variation across the wafer. And if hard bake isn’t consistent, you’re asking for scum, weak adhesion, and residual film that laughs at the stripper. The coater/developer IR heater has to deliver repeatable thermal behavior, cycle after cycle, without dumping particles into the stream or shrinking the process window. What actually matters under the hood We built the coater/developer IR heater around short-wave infrared (NIR) emitters—direct-coupled heating with closed-loop control. The payoff is wafer-level uniformity within ±0.1°C across the bake plate, so the photoresist gets the same thermal budget from edge to edge. Response is sub-second, which lets you hold ramp rate and soak time tight. It’s cleanroom Class 1–100 compatible, thanks to a low-outgassing assembly and a zero-particle architecture that keeps particle counts flat, even during long production runs. The heater drops into standard coater/developer platforms and is engineered for 24/7 operation, with stable output across thousands of bake cycles. Why this plays in coater/developer tools Thermal repeatability is the lever that lines up a bunch of parameters at once. Tight temperature control improves photoresist flow and solvent removal during soft bake, and sets a stable crosslink state during hard bake. That shows up as tighter CD control, fewer rework lots, and less scrap. You also save energy because the heater hits setpoint fast and holds it without overshoot. Reliability shows up as uptime—fewer unplanned stops, fewer PM calls tied to bake-plate drift, and longer intervals between consumable swaps. What you need to get right up front Installation comes down to matching the tool’s mechanical envelope and control interface—double-check connector type, mounting tolerances, and available power. NIR systems are fast and uniform, but keep the emitter window clean; any film buildup will shift the setpoint and eat into uniformity. Build in routine inspection and controlled cleaning per cleanroom protocol. Match the heater to the exact bake profile and resist type—max power density isn’t the right call for every profile. When the integration is right, you get a wider process window without adding complexity.