Acceptor Delta-Doping for Schottky Barrier Enhancement on n-Type GaAs

1990 ◽  
Vol 181 ◽  
Author(s):  
S. J. Pearton ◽  
F. Ren ◽  
C. R. Abernathy ◽  
A. Katz ◽  
W. S. Hobson ◽  
...  
Keyword(s):  
Barrier Height ◽  
Control Sample ◽  
Schottky Contacts ◽  
Applied Bias ◽  
Fully Depleted ◽  
Barrier Heights ◽  
Effective Barrier ◽  
Delta Doping ◽  
Current Conduction ◽  
Increasing Temperature

ABSTRACTThe incorporation of thin C- or Zn-doped layers under metal Schottky contacts on n-type GaAs can lead to significant enhancements in the effective barrier height. A single C δ-doped layer (p = 1.3 × 1020 cm–3) within 100 Å of the surface leads to a barrier height of ∼0.9 eV, a significant increase over the value for a control sample (∼0.75 eV). The use of two sequential δ-doped layers can lead either to a further enhancement in barrier height, or a decrease depending on whether these layers are fully depleted at zero applied bias. The temperature dependence of current conduction in barrier-enhanced diodes was measured. Both the ideality factor and breakdown voltage degrade with increasing temperature. Zinc δ-doping in a similar fashion produces barrier heights of 0.81 eV for one spike and 0.95 eV for two spikes.

Quasi-Schottky Diodes on (n)In.53Ga.47as with Barrier Heights of 0.6 eV

1991 ◽  
Vol 240 ◽  
Author(s):  
M. Marso ◽  
P. Kordoš ◽  
R. Meyer ◽  
H. Lüth
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Schottky Diodes ◽  
Reverse Current ◽  
Surface Layers ◽  
Fully Depleted ◽  
Barrier Heights ◽  
Effective Barrier ◽  
Basic Parameters ◽  
And Control

ABSTRACTThe modification and control of the Schottky barrier height on (n)InGaAs is an important tool at the device preparation as the barrier height is very low, øB° = 0.2 eV. We report about the Schottky barrier enhancement on (n)InGaAs by thin fully depleted surface layers of high doped (p+)InGaAs. Structures with different thicknesses of (p+)InGaAs in the range from 8 to 80 nm were grown by LP MOVPE technique and quasi-Schottky diodes with different contact areas were prepared using titanium as a barrier metal. I-V and I-T characteristics were measured and analysed to obtain basic parameters of prepared diodes, i. e. ideality factor n, effective barrier height øB, series resistance Rgand reverse current density JR (1V). The barrier height enhancement increases with the thickness of the (p+)-layer. Effective barrier heights of øB>0.6 eV, i.e. higher than reported until now, can be obtained with the surface layers of (p+)InGaAs with thicknesses exceeding 25 nm.

Quantum mechanical tunnelling: the missing term to achieve sub-kJ mol−1 barrier heights

2021 ◽  
Author(s):  
Sebastian Kozuch ◽  
Tim Schleif ◽  
Amir Karton
Keyword(s):  
Barrier Height ◽  
Quantum Mechanical ◽  
Effective Barrier Height ◽  
Quantum Tunnelling ◽  
Barrier Heights ◽  
Effective Barrier

Quantum tunnelling can lower the effective barrier height, creating a discrepancy between experiment and theory.

Analysis of temperature-dependent Schottky barrier parameters of Cu–Au Schottky contacts to n-InP

2012 ◽  
Vol 90 (1) ◽  
pp. 73-81 ◽  
Author(s):  
V. Lakshmi Devi ◽  
I. Jyothi ◽  
V. Rajagopal Reddy
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Gaussian Distribution ◽  
Ideality Factor ◽  
Thermionic Emission ◽  
Schottky Contacts ◽  
Temperature Dependent ◽  
Semiconductor Interface ◽  
Zero Bias ◽  
Barrier Heights

In this work, we have investigated the electrical characteristics of Au–Cu–n-InP Schottky contacts by current–voltage (I–V) and capacitance–voltage (C–V) measurements in the temperature range 260–420 K in steps of 20 K. The diode parameters, such as the ideality factor, n, and zero-bias barrier height, Φb0, have been found to be strongly temperature dependent. It has been found that the zero-bias barrier height, Φb0(I–V), increases and the ideality factor, n, decreases with an increase in temperature. The forward I–V characteristics are analyzed on the basis of standard thermionic emission (TE) theory and the assumption of gaussian distribution of barrier heights, due to barrier inhomogeneities that prevail at the metal–semiconductor interface. The zero-bias barrier height Φb0 versus 1/2kT plot has been drawn to obtain the evidence of a gaussian distribution of the barrier heights. The corresponding values are Φb0 = 1.16 eV and σ0 = 159 meV for the mean barrier height and standard deviation, respectively. The modified Richardson plot has given mean barrier height, Φb0, and Richardson constant, A**, as 1.15 eV and 7.34 Acm−2K−2, respectively, which is close to the theoretical value of 9.4 Acm−2K−2. Barrier heights obtained from C–V measurements are higher than those obtained from I–V measurements. This inconsistency between Schottky barrier heights (SBHs) obtained from I–V and C–V measurements was also interpreted. The temperature dependence of the I–V characteristics of the Au–Cu–n-InP Schottky diode has been explained on the basis of TE mechanism with gaussian distribution of the SBHs.

Evolution of Ti Schottky Barrier Heights on n-Type GaN with Annealing

1996 ◽  
Vol 449 ◽  
Author(s):  
Michèle T. Hirsch ◽  
Kristin J. Duxstad ◽  
E. E. Haller
Keyword(s):  
Barrier Height ◽  
Schottky Diodes ◽  
Electron Beam Evaporation ◽  
Organic Vapor ◽  
Barrier Heights ◽  
Effective Barrier ◽  
Mott Model ◽  
Current Voltage ◽  
Metal Organic ◽  
Ti Films

ABSTRACTWe report the effect of mild annealing on Ti Schottky diodes on n-type GaN. The Ti films were deposited by electron beam evaporation on n-type GaN grown by metal organic vapor deposition. We determine the effective barrier height Ф60 by current-voltage measurements as a function of temperature. The as-deposited Ti contacts show rectifying behavior with low barrier heights Ф60 ≤ 200meV. At annealing temperatures as low as 60°C we observe an increase of the barrier height to values of 250meV. After annealing at 230°C and above a stable barrier height of 450meV is measured. The increase in barrier height is not due to any macroscopic interfacial reaction. The origin of the observed changes are discussed in terms of the Schottky-Mott model and possible microscopic interfacial reactions.

The Interface for Cryogenic-Processed Metal/Inp

1993 ◽  
Vol 318 ◽  
Author(s):  
L. He ◽  
W.A. Anderson ◽  
J. Palmer ◽  
Z. Shi
Keyword(s):  
Barrier Height ◽  
Metal Film ◽  
Schottky Contacts ◽  
Leakage Currents ◽  
Barrier Heights ◽  
Low Leakage ◽  
Better Than

ABSTRACTAu and Pd Schottky contacts to n-InP produce extremely high barrier heights and low leakage currents when deposition is on a substrate cooled to 77K. Extensive chemical and structural analyses indicate that this process causes the metal film to be continuous at 50Å, much better than in standard processing. Stoichiometry of InP near the surface is better maintained with this process. A thin P:O compound may exist at the interface which also contributes to a high barrier height.

TEMPERATURE-DEPENDENT MODIFICATIONS OF Ag/SiO2/p-Si SCHOTTKY CONTACTS FORMED AT 20 K

2010 ◽  
Vol 09 (03) ◽  
pp. 135-138
Author(s):  
A. ALI ◽  
M. YASAR ◽  
F. NASIM ◽  
A. S. BHATTI
Keyword(s):  
Grain Size ◽  
Barrier Height ◽  
Ideality Factor ◽  
Thermal Evaporation ◽  
Schottky Contacts ◽  
Temperature Dependent ◽  
Ideal Behavior ◽  
Annealing Temperatures ◽  
Average Grain Size ◽  
Increasing Temperature

The Schottky contacts of Ag/SiO2 /p- Si were fabricated by thermal evaporation at 20 K. The effect of annealing temperatures varying from 373 to 773 K on the morphology and electrical properties of these contacts was investigated. The average grain size increased while the density of grains decreased with increasing temperature. Ideality factor initially observed was as high as 4.15 with a low barrier height of 0.04 eV for contact grown at 20 K. Annealing resulted in shift of ideality factor and barrier height towards ideal behavior. Thus, it is demonstrated that Ag/SiO2 /p- Si contacts grown at low temperature can be modified by annealing.

scholarly journals Electrical Properties of Rapidly Annealed Ir and Ir/Au Schottky Contacts on n-Type InGaN

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
V. Rajagopal Reddy ◽  
B. Prasanna Lakshmi ◽  
R. Padma
Keyword(s):  
Barrier Height ◽  
Annealing Temperature ◽  
Schottky Diodes ◽  
Forward Bias ◽  
Interface State ◽  
Schottky Contacts ◽  
Barrier Heights ◽  
Current Voltage ◽  
State Densities ◽  
Optimum Annealing Temperature

The effect of annealing temperature on electrical characteristics of iridium (Ir) and iridium/gold (Ir/Au) Schottky contacts to n-type InGaN have been investigated by means of current-voltage (I-V) and capacitance-voltage (C-V) techniques. It is observed that the barrier height of Ir/n-InGaN and Au/Ir/n-InGaN Schottky diodes increases after annealing at 300∘C for 1 min in N2 ambient compared to the as-deposited. However, the barrier heights are found to be decreased somewhat after annealing at 500∘C for the both Ir and Ir/Au Schottky contacts. From the above observations, it is clear that the optimum annealing temperature for both Ir and Ir/Au Schottky contacts is 300∘C. Moreover, the barrier height (ϕb), ideality factor (n) and series resistance (RS) are determined using Cheung’s and Norde methods. Besides, the energy distribution of interface state densities are determined from the forward bias I-V characteristics by taking into account the bias dependence of the effective barrier height. Based on the above results, it is clear that both Ir and Ir/Au Schottky contacts exhibit a kind of thermal stability during annealing.

scholarly journals Excitation Intensity and Temperature-Dependent Performance of InGaN/GaN Multiple Quantum Wells Photodetectors

Electronics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1840
Author(s):  
Alessandro Caria ◽  
Carlo De Santi ◽  
Ezgi Dogmus ◽  
Farid Medjdoub ◽  
Enrico Zanoni ◽  
...  
Keyword(s):  
Barrier Height ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Excitation Intensity ◽  
Multiple Quantum ◽  
High Excitation ◽  
Effective Barrier Height ◽  
Effective Barrier ◽  
Increasing Temperature ◽  
Carrier Escape

In this article, we investigate the behavior of InGaN–GaN Multiple Quantum Well (MQW) photodetectors under different excitation density (616 µW/cm2 to 7.02 W/cm2) and temperature conditions (from 25 °C to 65 °C), relating the experimental results to carrier recombination/escape dynamics. We analyzed the optical-to-electrical power conversion efficiency of the devices as a function of excitation intensity and temperature, demonstrating that: (a) at low excitation densities, there is a lowering in the optical-to-electrical conversion efficiency and in the short-circuit current with increasing temperature; (b) the same quantities increase with increasing temperature when using high excitation power. Moreover, (c) we observed an increase in the signal of photocurrent measurements at sub-bandgap excitation wavelengths with increasing temperature. The observed behavior is explained by considering the interplay between Shockley–Read–Hall (SRH) recombination and carrier escape. The first mechanism is relevant at low excitation densities and increases with temperature, thus lowering the efficiency; the latter is important at high excitation densities, when the effective barrier height is reduced. We developed a model for reproducing the variation of JSC with temperature; through this model, we calculated the effective barrier height for carrier escape, and demonstrated a lowering of this barrier with increasing temperature, that can explain the increase in short-circuit current at high excitation densities. In addition, we extracted the energy position of the defects responsible for SRH recombination, which are located 0.33 eV far from midgap.

Sign in / Sign up

Export Citation Format

Share Document