On the 300mm line, soft bake isn’t optional — it’s your thermal budget, plain and simple. A 2°C swing across the wafer can shift CD by nanometers, and the vacuum chamber only makes any drift worse. We built our vacuum-chamber IR heater to take that variability out of the equation, so temperature stays repeatable where lithography and thin-film work need it. What matters under the hood We run short-wave infrared (NIR) emitters in a rapid-response quartz envelope, tuned to settle fast under vacuum. Wafer-plane uniformity holds at ±0.1°C across the process window, and batch-to-batch repeatability stays within ±0.5°C. The heater body is engineered for Class 1–100 cleanroom integration: low-outgassing materials and a particle-minimized layout that keeps contamination off the wafer. Output stays stable from idle to full load, and the control loop compensates for emissivity shifts across patterned wafers without overshoot. Why this lands in photoresist processing In soft bake, hard bake, and post-exposure bake, temperature precision directly buys you CD control, consistent sidewall profiles, and fewer rework lots. The heater is clean, non-contact, so thermal lag drops and you don’t introduce hot-zone contamination. That keeps particle counts stable and defect performance predictable. For advanced nodes, that means higher first-pass yield and less scrap. For the fab, it means the thermal process behaves the same at 3 a.m. as it does at 3 p.m. What you need to plan for The unit has to be thermally anchored tight to the chamber block to hit the uniformity target — misalignment shows up as a measurable gradient. You’ll get through commissioning quickly once you tune the emissivity tables for your film stack. After that, it runs with minimal maintenance, but emitter output does decay over time. Schedule replacements based on uptime and how sensitive your process is.