Transient phenomena in sub-bandgap impact ionization in Si n-i-p-i-n Diode

Das B, Schulze J, Ganguly U (2018)

Publication Type: Journal article

Publication year: 2018

Journal

IEEE Transactions on Electron Devices Institute of Electrical and Electronics Engineers (IEEE)

Book Volume: 65

Pages Range: 3414-3420

Article Number: 8401800

Journal Issue: 8

DOI: 10.1109/TED.2018.2846360

Abstract

Sub-bandgap (SBG) impact ionization (II) enables steep subthreshold slope that enable devices to overcome the thermal limit of 60 mV/decade. This phenomenon at low voltage enables various applications in logic, memory, and neuromorphic engineering. Recently, we have demonstrated sub-0.2-V II in n-i-p-i-n diode experimentally primarily based on steady-state analysis. In this paper, we present the detailed experimental transient behavior of SBG-II in n-i-p-i-n. The SBG-II generated holes are stored in the p-well. First, we extract the leakage mechanism from the p-well to show two mechanisms: 1) recombination-generation and 2) over the barrier (OTB), where OTB dominates when barrier height φb< 0.59 eV. Second, we analytically extract the SBG-II current ( III ) at 300 K from the experimental results. The drain current ( ID ), electric field ( E- field ), and III are plotted in time. We observe that III increase as E- field reduces which indicates that E -field does not primarily contribute to III. Furthermore, ID shows two distinct behaviors: 1) III (ID ) is constant at the beginning and 2) eventually 'universal' III (ID ) is linear, i.e., III=k\times ID where k = 10-3 ; we also show that the electrons primarily contributing to ID are directly incapable of II due to insufficient energy ( < Eg ). Fischetti's model showed that SBG-II is primarily caused by 'hot' electrons that accept energy in an Auger-like process from 'cold' drain electrons to enable SBG-II. We speculate that if ID electrons 'heat-up' the cold drain electrons, which would further energize the hot electrons to produce the observed III(ID ) universal dependence.

Authors with CRIS profile

Jörg Schulze

Involved external institutions

Indian Institute of Technology Bombay IN India (IN) Universität Stuttgart DE Germany (DE)

How to cite

APA:

Das, B., Schulze, J., & Ganguly, U. (2018). Transient phenomena in sub-bandgap impact ionization in Si n-i-p-i-n Diode. IEEE Transactions on Electron Devices, 65(8), 3414-3420. https://doi.org/10.1109/TED.2018.2846360

MLA:

Das, Bhaskar, Jörg Schulze, and Udayan Ganguly. "Transient phenomena in sub-bandgap impact ionization in Si n-i-p-i-n Diode." IEEE Transactions on Electron Devices 65.8 (2018): 3414-3420.

BibTeX: Download