Abstract
The practical range of low-energy electrons in thin Al2 O3 films has been measured. Films ranging in thickness from 85 to 5000 A were investigated. Results are in close agreement with the predictions of Bethe and the results obtained by Hoffman for 1000-3000 A Al2 O3 films. The practical range-energy relation obtained was found to be R=0.0115E1.35, where R is expressed in mg/cm2 and E in kev.