CALCULATION OF CRITICAL LAYER THICKNESS CONSIDERING THERMAL STRAIN INSI1-XGEX SI STRAINED-LAYER HETEROSTRUCTURES/

In this article, interactions of thermal strain in growth of Si1-xGex strained-layers on Si are analyzed. A formula of critical layer thickn ess (h(c),) is obtained based on energy balance considering thermal st rain under the assumption that the screw dislocation energy density eq uals to the sum of the areal strain energy density and thermal strain energy density. The relationship between the thermal expansion coeffic ient associated with thermal strain and Ge content x is linear. Our ca lculated values for h(c) of Si1-xGex strained layers on Si substrates versus mismatch, considering thermal strain, are better agreement with measurements of h(c) by People and Bean. (C) 1998 American Institute of Physics.