Mechanical characteristics of hydrogen-implanted crystalline silicon after post-implantation annealing

Knowing the mechanical properties of single crystal silicon after implantation with hydrogen and annealing are important for "smart cut" process and in improving ultra-precision cutting of silicon. There is limited information on hardness and modulus of such silicon. In this article, the effect of hydrogen implantation dose and post-implantation annealing on silicon hardness and modulus were investigated. Continuous implanted silicon layers, from the surface to the depth of similar to 500 nm, were produced. Samples with three different implantation doses and with post-implantation annealing at 350 degrees C and 400 degrees C were prepared. Hardness and modulus were obtained through dynamic nanoindentation, while structural properties were evaluated by Rutherford backscattering spectroscopy and high resolution x-ray diffraction. Hardness and modulus were significantly reduced after annealing for the highest implantation dose. With the annealing, the implantation-induced strain had the least relaxation for the lowest implantation dose. The obtained results could be useful for understanding the role of hydrogen in nano cutting of hydrogen-implanted silicon. (C) 2018 Elsevier Ltd. All rights reserved.