A method for obtaining nbti degradation model based on non-uniform distribution of interface traps

Abstract

The invention discloses an NBTI degradation model obtaining method based on nonuniform distribution interface traps. The method comprises the steps that 1, interface trap distributions in different zone of an MOS device are divided to obtain total distribution frame of the interface traps; 2, according to geometric construction, the interface trap distribution density in each zone is calculated, and the total density of the nonuniform distribution interface traps is obtained; 3, threshold voltage deviation caused by NBTI is obtained according to the deltaNIT total density, and an NBTI degradation model based on geometric construction analysis is obtained. The actual distribution situation of the interface traps produced by an NBTI effect is incorporated in the model, accordingly the total density of interface trap charges produced in the MOS device can be accurately calculated, thus a threshold voltage degradation model is obtained, few fitting parameters are required, the applicability is wide, and the model provides more accurate precision for device reliability.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, in particular to an accurate acquisition method of an NBTI degradation model based on non-uniformly distributed interface traps. Background technique [0002] As semiconductor process technology enters the deep submicron era, negative bias temperature instability (NBTI) has become one of the main factors affecting device performance degradation and lifespan. A model that accurately describes the physical mechanism and performance of device degradation is an important aspect of device reliability. A big problem that needs to be solved and perfected urgently. It has been proposed that the interface traps caused by negative bias temperature instability are not uniformly distributed in the channel, and the NBTI degradation strongly depends on the device geometry, especially the length and width of the channel. But so far this aspect has received little attention. The generally accepted react...

AI Technical Summary

Problems solved by technology

[0004] Since the existing NBTI degradation model does not have an accurate calculation of the distribution of interface traps in the channel edge region, in order to obtain a more accurate degradation model formula, the present invention proposes a method that considers the influence of device channel length and width geometry, based on The NBTI degradation model acquisition method of non-uniformly distributed interface traps, the model obtained by this method has high physical significance, and has certain scalability and universality

Images