Abstract: Biaxial strain technology is a promising way to improve the mobility of both electrons and holes,while 〈100〉 channel direction appears as to be an effective booster of hole mobility in particular.In this work,the impact of biaxial strain together with 〈100〉 channel orientation on hole mobility is explored.The biaxial strain was incorporated by the growth of a relaxed SiGe buffer layer,serving as the template for depositing a Si layer in a state of biaxial tensile strain.The channel orientation was implemented with a 45° rotated design in the device layout,which changed the channel direction from 〈110〉 to 〈100〉 on Si (001) surface.The maximum hole mobility is enhanced by 30% due to the change of channel direction from 〈110〉 to 〈100〉 on the same strained Si (s-Si) p-MOSFETs,in addition to the mobility enhancement of 130% when comparing s-Si pMOS to bulk Si pMOS both along 〈110〉 channels.Discussion and analysis are presented about the origin of the mobility enhancement by channel orientation along with biaxial strain in this work.

Key words: p-MOSFET, strained Si, channel direction, hole mobility enhancement