UHV-IMMA Development and Application to Hydrogen Detection

Abstract
An ultra high vacuum ion micro-probe mass analyser (UHV-IMMA) has been developed. Effective differential pumping together with other UHV technique design considerations enables observations to be made in an ultra high vacuum of better than 1×10-7 Pa. The UHV-IMMA was used to observe the hydrogen content ratio in hydrogenated amorphous silicon (a-Si:H) and the peak height ratio H+/Si+ observed was close to proportional to the hydrogen content ratio H/Si obtained by IR. The UHV-IMMA was found to have the capability of allowing observations of the hydrogen content in solids at less than 0.01 at.% to be made.