Analysis of SRAM cell characteristics based on high-k metal-gate strained Si/Si1−xGex MOSFET with consideration of NBTI/PBTI

In this paper, we investigate the characteristics of SRAM cells with high-k metal-gate Si/Si_1-xGe_x dual channel structures. The characteristics are compared with those of the unstrained structures. The results show that the strain degrades read SNM slightly while increases read current considerably. In addition, it increases writability while decreases standby power. Moreover, NBTI and PBTI effect for two cases of symmetrical and asymmetrical stresses is investigated. In the symmetrical case, read and write stability don´t reduce while read current decreases. For the case of the asymmetrical stress, both read and write stabilities degrade. In addition, read current decreases more than that of the symmetrical case. The results demonstrate while NBTI and PBTI cause less read current reduction in the strained cells, the degradations of other metrics are comparable to those of the unstrained cells.