Role of Schottky barrier height modulation on the reverse bias current behavior of MIS(P) tunnel diodes
Journal
IEEE Access
Journal Volume
9
Pages
163929-163937
Date Issued
2021
Author(s)
Abstract
Current and capacitance characteristics of Al/SiO2/Si(p) metal-insulator-semiconductor tunnel diode (MISTD) with oxide thickness in the range of about 2-4 nm were fabricated and studied in detail in this work. We found that the saturation reverse bias current will increase with oxide thickness in this range of oxide thickness. This non-intuitive phenomenon is caused by different levels of Schottky barrier height modulation (SBHM), which leads to the injection of the majority from metal. The majority current of Al/SiO2/Si(p) MISTD is usually neglected because of the blocking of the oxide layer and the Schottky barrier. The mechanism and numerical analysis of SBHM are discussed in this work. SBHM is significant when the oxide is thin enough for the majority to tunnel from metal to semiconductor and thick enough to hold a part of the minority inversion layer. In this specific oxide thickness range, increasing oxide thickness will increase the ability to hold the inversion layer, thus leading to higher oxide voltage (Vox) and stronger SBHM. As a result, we find that stronger SBHM lets more majority have enough energy to inject from metal to semiconductor and cause higher reverse saturation current in MISTD with thicker oxide. With the numerical analysis in our work, we also predict this non-intuitive phenomenon will start to turn around when oxide thickness is thicker than about 33?. This phenomenon indicated that majority current is an un-neglectable component when the oxide is thick enough to hold the inversion layer partially. The analysis in this work is also helpful to complete the missing part of the theory describing the current behavior of MISTD. ? 2021 Institute of Electrical and Electronics Engineers Inc.. All rights reserved.
Subjects
Metal-insulator-semiconductor (MIS)
Schottky barrier height
Schottky diode
Ultra-thin oxide
Electric resistance
Indium compounds
Metal analysis
Metal insulator boundaries
Metals
MIS devices
Modulation
Schottky barrier diodes
Semiconductor diodes
Semiconductor insulator boundaries
Semiconductor junctions
Semiconductor metal boundaries
Silicon on insulator technology
Substrates
Metal-insulator-semiconductor
Metal-insulator-semiconductors
Oxide thickness
Schottky barrier height modulation
Schottky barriers
Schottky diodes
Schottky-barrier heights
Semiconductor device measurements
Steady state
Capacitance
Type
journal article