Biaxially strained germanium micro-dot array by hydrogen ion implantation

Although strain engineering is an effective method to modify the bandgap of germanium for germanium-based microelectronic, the introduction of biaxial tensile strain with a particular pattern to germanium is challenging. Herein, a facile approach to produce biaxially strained germanium micro-dot arrays by hydrogen ion implantation is described. By changing the ion implantation and annealing conditions, the morphology of the micro-dots can be optimized and the biaxially tensile strain can be tuned to a maximum value of 0.6%. This method which is compatible with mainstream complementary metal-oxide-semiconductor processing can be extended to strain engineering in wafer scale.