Static Noise Margin Analysis of Sub-threshold SRAM Cells in Deep Sub-micron Technology

Supply voltage reduction in SRAMs: Impact on Static Noise Margins

“…Expressions for above -threshold SNM are given in Seevinck et al [2] and Bhavnagarwala et al [3] and for subthreshold SNM are given in Calhoun and Chandrakasan [4] and Welling and Zory [5]. In [2] an explicit analytic expression for the SNM based on long channel models as a function of device parameters and supply voltage is derived.…”

“…Bhavnagarwala et al [3] study of SRAM cell SNM reduction due to intrinsic threshold voltage fluctuations in uniformly doped minimum geometry MOSFETs. The work described in [5] investigates stability aspects of sub-threshold SRAM cells, deriving analytical expressions for the SNM as a function of circuit parameters, operating conditions and process variations. The noise margin of SRAM cells in low power conditions such as low supply voltage and source-body bias is experimentally determined, using a graphical approach in Cseveny et al [6] and Hook et al [8].…”

Scanning Noise Microscopy on Graphene Devices

“…In the area of nanoscale device research, various scanning probe microscopy (SPM) methods have been a workhorse for a device analysis because they provide nanoscale mapping of the electronic properties of the components in a nanodevice and thus enable versatile analyses of the device characteristics using only a single device. − For example, conducting atomic force microscopy (CAFM) is a powerful technique to measure electric currents for characterizing conductivity variations in nanoscale channels. − With Kelvin probe force microscopy, the work function variation on the surfaces of nanodevices can be observed. On the other hand, as the dimension and the operating voltage of modern electronic devices are reduced, its low-frequency noise is becoming a critical parameter determining the device performance. − Especially, 1/ f noise can be a significant problem in the devices based on nanomaterials such as graphene, − carbon nanotubes, − and nanowires. , In previous works, noise characteristics of various devices have been analyzed through the scaling behavior obtained from the noise measurement of multiple devices with different resistance values. − However, the fabrication of multiple devices for such noise analysis can be a labor-intensive work. Until now, SPM strategies have not been applied for nanodevice noise analysis.…”