New opportunities for SiGe and Ge channel p-FETs

Threshold voltage and transconductance shifting reliance on strained-SiGe channel dimension

“…Long channels are not well defined, although these channels are valid from 10 lm to tens of nanometers [1][2][3][4][5]. Aside from channel length, Bedell et al considered channel width as another factor that may determine the drive current in SiGe and Ge channels [2]. The present study provides a basis for channel width-to-length (W/L) ratio comparison, which indicates that the dominance of longitudinal or transverse configuration depends on this ratio.…”

“…The strained layer enhances the hole mobility and is compatible with the CMOS process. Many studies have reported that a long p-channel is enhanced more than a short channel is [1][2][3][4][5]. Increasing the channel length augments the hole velocity and mobility in a SiGe channel [1].…”

“…Increasing the channel length augments the hole velocity and mobility in a SiGe channel [1]. Long channels are not well defined, although these channels are valid from 10 lm to tens of nanometers [1][2][3][4][5]. Aside from channel length, Bedell et al considered channel width as another factor that may determine the drive current in SiGe and Ge channels [2].…”

“…The mobility can be degraded when the negative piezoresistance coefficient of the transverse [1 1 0] p-channel is beyond a critical W/L ratio. Nevertheless, the critical W/L ratio may require further verification because of other factors reported in literature, such as the capsulated Si (capsulated silicon) thickness [8] and the Ge-content Si 1Àx Ge x [2,9], which can be sensitive to the device performance. In addition, a high Ge content and a thick Si 1Àx Ge x have been reported with a decreased threshold voltage (V T ) [9].…”

Performance evaluation of p-channel FinFETs using 3D ensemble Monte Carlo simulation

“…As a result, Intel's adoption of FinFET technology at the 22nm CMOS technology [1] has invigorated the interest in multigate MOSFET optimization and scaling. In addition to this the use of high mobility materials in place of conventional Si has gained an increased interest to further boost performance, with Ge and SiGe alloys [2], [3] strong candidates for p-channel transistors. The FinFET architecture lends itself to further enhancement via both uniaxial and biaxial strain and the exploitation of alternative surface orientations for the channel.…”