AFM studies of hydrogen implanted silicon

The effects of hydrogen implantation on the surface microtopography of 100:silicon single crystals were analyzed by means of atomic force microscopy AFM.technique. The main objective of the study was to get a new insight into the processes occurring during the early stages of hydrogen blister formation in SmartCutw technology used in Silicon-on-Insulator devices manufacturing. The results revealed that hydrogen blistering sets in at doses about 4=1016 Hq2rcm2 by a formation of small, few tens of nanometer high bubbles. The increase of the implantation dose results first in the growth of the bubbles up to few hundreds nm and then in the formation of the next generation of small hydrogen clusters. The detailed analysis of the SiO2 surface layer formed on the silicon crystals indicated the presence of small, few nm in size, hillock-like structures which can be responsible for the difficulties in SiO2–SiO2face-to-face bonding. A possible use of implantation induced microtopography changes in Microelectronics and Micromechanical Systems applications is also discussed. q1999 Elsevier Science B.V. All rights reserved.