Transene Company manufactures traditional BOE (buffered oxide etchants) suitable for your process as well as a proprietary formulation Buffer HF Improved. Feel free to visit our website www.transene.com or contact me directly for more information. Christopher Christuk Transene Company Tel: 978 777 7860 Email: Christopher@transene.com -----Original Message----- From: Daniel Dias [mailto:daniel.dias@physik.tu-darmstadt.de] Sent: Monday, September 08, 2003 6:06 AM To: mems-talk@memsnet.org Subject: [mems-talk] HF/NH4F etching of diffractive optical elements Hello, I am coming from the fields of diffractive optics and I have the following questions: I would like to etch microstructures into a fused silica substrate with a wet chemical etch process. I have heard that HF/NH4F is appropriate to do that. The structures have lateral feature sizes of 1-10 microns. The elements should be etched approximately 1-2 micron deep. Has anyone made experience with similar processes and even fabricated diffractive optical elements in quarz glas? For an answer I would be grateful. Thanks in advance Daniel