We have studied the direct bonding of platinum to silicon for applications where an electrical conduction through the bonding interface is desired. Platinum has been deposited on silicon wafers by mean of physical vapor deposition. Levels of surface roughness compatible with direct bonding have been achieved for the deposited Pt thin films. The surface preparation of the Pt films was performed using a diluted HF or H2SO4 based chemistry. The sequence used allowed achieving the direct bonding of Pt to Si. The post bonding thermal treatments have been investigated. Such thermal treatments lead to the silicidation of the platinum layer. Adhesion between the wafers after the thermal treatments has been strengthened as measured by Maszara's blade technique (440 mJ/cm(2) were achieved after a 300 degrees C thermal treatment). The morphological evolution of the buried silicide layer has been followed for different thermal budget by scanning electron microscopy. The higher thermal budgets probed (i.e., 700 degrees C, 1 h) resulted in the agglomeration of the buried silicide layer, but without observing debonding of the two silicon wafers. The vertical electrical conduction has been measured for the final sample annealed at 300 degrees C. Schottky type contacts have been obtained between the semiconductor and the silicide. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3529948] All rights reserved.