Narrow-width effects of shallow trench-isolated CMOS with n/sup +/-polysilicon gate

The impacts of high tensile stress CESL and geometry design on device performance and reliability for 90nm SOI nMOSFETs

“…Besides, previous studies [24,25] reported that nMOSFET with STI show an inverse-narrow-width effect caused by fringing electric fields, enhancing the channel edge current. Furthermore, the channel edge current density will also increase rapidly with the gate width decrease [26]. In the subthreshold region, owing to larger channel current density, device with narrow width possesses offstate leakages; thus degrading subthreshold slope and lowering the threshold voltage as shown in Fig.…”

A test structure to separately analyze CMOSFET reliabilities around center and edge along the channel width

“…On the other hand, the isolation technology has shifted from the conventional LOCOS to the shallow trench isolation (STI) [3] as the technology nodes have been scaled down to submicron area, and the comparison of the device reliability dependent on the isolation technologies have been reported [4][5][6]. It is expected that the STI technology may modulate the high electric fields near the channelwidth edge resulting in the reliability variation along the channel-width direction, because the narrow-width or the inverse-narrow-width effects are largely influenced by the STI process [7,8]. Until now, the reliability comparison between the buried-and the surface-channel narrow-width p-MOSFETs fabricated by STI was reported [9].…”

Electrical characteristics of CMOSFETs with gates crossing source/drain regions at 90° and 45°

“…[5] due to the bird's beak less than 0.05pm with the high channel stop doping and the low buried channel doping near the trench-isolation edges, respectively. It comes from the conventional short channel effect that VT values observed in p-MOSFETs with W22pm and L=0.8pm are a little larger than those with LzOSpm.…”

“…This difference might be explained due to a three-dimensional effect [9] which is not considered in the simple theory; the effective W which has L of 0.5pm is so narrow as W-L,=0.3pm, and the currents flowing in this region are strongly affected by the edge currents determined by the effective W/L ratio of 1/2 given by Eq. (5). Consequently, the data point is aligned on the extrapolated point from the dotted line calculated by Eq.…”