Comment
Author: Admin | 2025-04-28
Of this variation is comparable to the sizes of individual devices, so each device can vary independently.Process variations can classified as follow:Inter-die variation or die-to-die: Inter-chip variations are variations that occur from one die to next, meaning that the same device on a chip has different features among different die of one wafer, from wafer to wafer and from wafer lot to wafer lot. Die-to-die variations have a variation radius larger than the die size including within wafer, wafer to wafer, lot to lot and fab to fab variations [12].Intra-die or within-die variation: Intra-die variations are the variations in device features that are present within a single chip, meaning that a device feature varies between different locations on the same die. Intra-chip variations exhibit spatial correlations and structural correlations. Front-end variation: Front-end variations mainly refer to the variations present at the transistor level. The primary components of the front end variations entail transistor gate length and gate width, gate oxide thickness, and doping related variations. These physical variations cause changes in the electrical characteristics of the transistors which eventually lead to the variability in the circuit performance.Back-end variation: Back-end variations refer to the variations on various levels of interconnecting metal and dielectric layers used to connect numerous devices to form the required logic gates.In practice, device features vary among the devices on a chip and the likelihood that all devices have a worst-case feature is extremely small. With increasing awareness of process variation, a number of techniques have been developed
Add Comment