We investigated the oxidation of hydrogen terminated Si (1 0 0) surfaces stored in Fab air environment. Hydrogen termination for extended queue times with wet and dry clean techniques is investigated. Comparison of X-ray photoelectron spectroscopy (XPS) data and empirical results from Si capping layer are used to determine re-oxidation of the Si surface over extended queue times. H-2 pre-bake efficiency with the best clean method, 100: 1 HF, in situ rinsed with degasified DI water was tested. 2 min 850 degrees C and 900 degrees C H-2 bakes, at 10 Torr pressure, both resulted in atomically clean surfaces below SIMS detectable for up to 96 h queue time in lab ambient (controlled 35-40% relative humidity and temperature range of 22-25 degrees C). (C) 2008 Elsevier B. V. All rights reserved.