Laser induced dry etching of vias in glass with non-contact masking

摘要

Disclosed is an apparatus and method for etching a glass substrate by laser induced dry etching. The apparatus features a housing including a vacuum chamber for receiving the substrate; a vacuum pump coupled to the chamber for evacuating the chamber; a gas source coupled to the chamber for supplying a halogen base gas which is capable of wetting the substrate surface and forming a glass etching specie when activated; a laser source for transmitting a light beam of predetermined wavelength and intensity through the gas; and a mask optically coupled to the laser source for patterning the light beam and also coupled to the chamber so that the light patterned by the mask may fall upon the substrate causing excitation thereof and activation of an etch specie for etching the substrate in conformity with the patterned light. The disclosed method comprises the steps of loading the substrate into a vacuum chamber; evacuating the chamber to a low pressure; controllably introducing a halogen base gas into the chamber to wet substrate surface layer to be etched; and introducing a patterned light beam of predetermined wavelength and intensity through the gas onto the surface layer causing excitation thereof and activation of an etch specie for etching the substrate in conformity with the patterned light. The laser light may be of the pulse type and of 10.6 microns wavelength in case of a CO2 laser or 249 nanometer or 193 nanometer wavelength in case of an eximer laser.