| 摘要 |
PURPOSE:An inexpensive glass base plate for hard mask that is made by dipping a base plate of soda glass in a melt containing potassium ions to replace the sodium ions with potassium ions on its surfaces, thus having hard layers on its surfaces. CONSTITUTION:A base plate of soda glass such as soda lime glass is dipped in a liquid containing potassium ions such as KNO3 melt at about 460 deg.C for several to 24hr. Sodium ions are leached out of the surface of the glass plate in the depth of teens to 40mu from the surfaces and replaced with potassium ions. After the surface-hardening treatment, the plate is taken out, cooled, rinsed to give a soda glass base plate with hardened layers on surfaces replaced with potassium ions. There occurs no mouse-nipping and the electron-beam resist process can be applied, although it requires standing relatively high temperatures, and the improvement in the surface hardness results in elongation of use life inexpensively. |
