Horizontal Quartz Diffusion Tube Cleaner

Quartz tubes hold wafers inside diffusion and oxidation furnaces running at temperatures up to 1000 degrees Celsius, and each run leaves surface deposits from the furnace atmosphere and the process itself. Left on the tube, those deposits become particles and a source of metal contamination for the next batch of wafers, which is why the tube has to be stripped clean before it’s reloaded.

An acid spray, typically based on hydrofluoric, hydrochloric, or nitric acid, depending on what needs to be removed, dissolves the surface deposits, and the tube is then rinsed thoroughly with deionized water to make sure no acid residue remains before it’s dried. Acid concentration and exposure time are controlled carefully, since over-cleaning or incomplete rinsing can both affect tube performance in the next furnace run.

Yes. Fused quartz naturally contains trace metal impurities, and at furnace temperatures, those impurities can migrate out of the quartz and deposit onto the wafer surface, a separate source of contamination from whatever the process itself leaves on the tube wall. This is one reason both quartz material purity and a thorough acid clean matter for the same furnace step.

A T/C sheath cleaner cleans the thermocouple sheaths inside the furnace tube that monitor process temperature. Because the sheath is exposed to the same furnace atmosphere and deposits as the tube itself, it requires the same acid spray and rinse treatment to remain accurate and particle-free, which is why it’s offered as a matched option rather than as a separate cleaning step.

Modutek builds these stations with one-piece construction up to 10 feet in length, so long furnace tubes can be cleaned as a single unit rather than in sections, avoiding the seams and joints that could otherwise trap particles.