Lithography Radiation Effects Study.
Abstract
An experimental x-ray lithography facility for irradiating thin films of a photoresist next to a gold mask is described. The x-ray irradiance and PMMA irradiation times are estimated for several target elements with characteristic x-ray lines in the 1-3 keV energy range. A gold mask (6800 A thick) deposited with films of carbon 100, 220, 520 and 710 A thick were placed next to films of PBS resist and irradiated with x-rays from A1, Ag, and Ti targets bombarded by 10 keV electrons. The exposed PBS was etched for a fixed time interval, and the thickness of the etched resist next to the varying film thickness of carbon was measured by optical ellipsometry. The plot of etched PBS thickness vs. carbon film thickness gave a measure of the depth of penetration of x-ray photoelectrons from the gold mask into the resist and a possible method of measuring dose-depth profiles at material interfaces at soft x-ray energies. A realistic, calculational model that includes source bremsstrahlung predicts fairly well experimental dose profile for the Au/C mask.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1984
- Accession Number
- ADA149552
Entities
People
- B. W. Murray