Title: Role of stress/strain mapping and random dopant fluctuation in advanced CMOS process technology nodes

Authors: T.P. Dash; J. Jena; E. Mohapatra; S. Das; S. Dey; C.K. Maiti

Addresses: Department of Electronics and Communication Engineering, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha 751030, India ' Department of Electronics and Communication Engineering, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha 751030, India ' Department of Electronics and Communication Engineering, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha 751030, India ' Department of Electronics and Communication Engineering, Silicon Institute of Technology, Bhubaneswar, Odisha 751024, India ' Department of Electronics and Communication Engineering, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha 751030, India ' Department of Electronics and Communication Engineering, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha 751030, India

Abstract: In this work, biaxial and uniaxial strain techniques are implemented in the channel for both p- and n-type FinFETs necessary for advanced CMOS applications. Stress/strain mapping in strained-Si (n-type) and strained-SiGe (p-type) channels (in trapezoidal tri-gate FinFET devices) are studied through three-dimensional (3D) numerical simulation, with particular focus on the enhancement of drain current. Following the strain/stress profiles simulated, the piezoresistive changes are implemented in the simulator to describe the strain effects on device operation. Further, we have investigated the impacts of random discrete dopant variability on the characteristics of a 14-nm gate length FinFET transistors (both n and p-type) using a 3D finite element quantum corrected drift-diffusion device simulator. We have also found the fluctuation of critical device parameters such as threshold voltage (VTH), sub-threshold slope (SS), on current (ION), and off state current (IOFF), etc., mainly originated from the randomness of distribution of the dopants.

Keywords: strained-Si; strained-SiGe; stress/strain mapping; FinFET; technology computer aided design; TCAD; random discrete dopants; RDD.

DOI: 10.1504/IJNBM.2020.107413

International Journal of Nano and Biomaterials, 2020 Vol.9 No.1/2, pp.18 - 33

Received: 20 Jul 2019
Accepted: 18 Sep 2019
Published online: 27 May 2020 *