Barrier Inhomogeneities at Schottky Contacts: Curved Richardson Plots, Idealities, and Flat Band Barriers

1992 ◽  
Vol 260 ◽  
Author(s):  
Jürgen H. Werner ◽  
Herbert H. Güttler ◽  
Uwe Rau
Keyword(s):  
Strong Influence ◽  
Schottky Contacts ◽  
Flat Band ◽  
Temperature Dependent ◽  
Quantitative Characterization ◽  
Barrier Heights ◽  
Temperature Coefficients ◽  
Barrier Inhomogeneities ◽  
Spatial Inhomogeneities

ABSTRACTEvaluating either curved Richardson plots or temperature-dependent ideality data allows for a quantitative characterization of spatial inhomogeneities at Schottky contacts. Applying the two independent methods to PtSi/Si diodes we obtain a standard deviation around 70mV for the barrier fluctuations. These results agree with those from the comparison of temperature-dependent current and capacitance barriers. We discuss also flat band barrier heights which should be used if one investigates the temperature dependence of fundamental Schottky barrier heights. Their temperature coefficients depend on metallization. For epitaxial NiSi2/Si contacts on (100) oriented Si we find a strong influence of interface crystallography on the temperature coefficients.

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.

Post Metallization Annealing Characterization of Interface Properties of High-κ Dielectrics Stack on Silicon Carbide

2008 ◽  
Vol 600-603 ◽  
pp. 771-774 ◽  
Author(s):  
Ming Hung Weng ◽  
Rajat Mahapatra ◽  
Nicolas G. Wright ◽  
Alton B. Horsfall
Keyword(s):  
Elevated Temperatures ◽  
Gate Dielectric ◽  
Flat Band ◽  
Interface Properties ◽  
Temperature Dependent ◽  
Oxide Charge ◽  
Before And After ◽  
Mis Capacitors ◽  
The Ideal

The interface properties of TiO2/SiO2/SiC metal-insulator-semiconductor (MIS) capacitors were investigated by C-V and G-V measurements over a range of frequencies between 10 kHz and 1 MHz from room temperature up to 500°C. Ledges from multiple traps were observed during high frequency (1 MHz) sweeps from inversion to accumulation during measurements at elevated temperatures. The high measuring temperature resulted in the annealing of the sample, where the existence of trap ledges was observed to be temperature dependent. For n-type substrate negative Qf causes the shift of the C-V curve to more negative gate bias with respect to the ideal C-V curve. These fixed oxide charge is substantially reduced after post metallization annealing (PMA). We report the flat band voltage, detail in reducing fixed oxide charge and temperature dependence of density of interface traps before and after annealing of TiO2 high-κ gate dielectric stacks on a 4H-SiC based device.

A New Approach to Temperature Dependent Ideality Factors in Schottky Contacts

1992 ◽  
Vol 260 ◽  
Author(s):  
Zs. J. Horváth
Keyword(s):  
Experimental Data ◽  
Low Temperatures ◽  
Schottky Diodes ◽  
Thermionic Emission ◽  
Schottky Contacts ◽  
Temperature Dependent ◽  
Model Calculations ◽  
New Approach ◽  
Barrier Heights ◽  
Thermionic Field Emission

ABSTRACTSchottky diodes often exhibit anomalous current-vol tage characteristics at low temperatures (T) with T dependent ideality factors (IF) and apparent barrier heights (BH) evaluated for the thermionic emission. In this paper theoretical expressions are first presented for the T dependences of the IF and the apparent BH for the thermionic-field emission (TFE) including the bias dependence of BH. Model calculations are reported, which has been performed using these expressions, and their results are compared with the available experimental data. It is shown that the T dependence of the 1 Fs and apparent BHs often may be explained self consistently by the TFE with anomalously high characteristic energies Eoo.

Characterization of SiGeC Using Pt(SiGeC) Silicide Schottky Contacts

1998 ◽  
Vol 533 ◽  
Author(s):  
Jeff J. Peterson ◽  
Charles E. Hunt ◽  
McDonald Robinson ◽  
Robin SCott
Keyword(s):  
Fermi Level ◽  
Conduction Band ◽  
Electrical Characterization ◽  
Schottky Contacts ◽  
Epitaxial Layers ◽  
Fermi Level Pinning ◽  
Barrier Heights ◽  
Xrd Studies ◽  
P Type

AbstractMaterial and electrical characterization of n-type and p-type Si1-x-yGex Cy epitaxial layers on Si(100) was performed using silicided platinum Schottky contacts. XRD studies show Pt silcidation of SiGeC proceeds from non-reacted Pt to Pt2(SiGeC) and completes with the Pt(SiGeC) phase similar to Pt/Si silicides, but Pt silicide reactions with SiGeC are shown to require higher temperatures than Pt reactions with Si. Electrical characterization of Pt(SiGeC) contacts to n-type Sil1-x-yGexCx/Si shows rectifying behavior with constant barrier heights of 0.67eV independent of composition, indicating Fermi level pinning relative to the SiGeC conduction band is occurring. Pt(SiGeC) contacts to p-type Si1-x-yGexCy/Si are also rectifying with barrier heights that track the variation of the SiGeC energy bandgap.

The effect of temperature on the electrical characterization of a poly(phenoxy-imine)/p-silicon heterojunction

e-Polymers ◽  
2016 ◽  
Vol 16 (1) ◽  
pp. 75-82
Author(s):  
Haci Ökkes Demir ◽  
Zakir Caldıran ◽  
Kadem Meral ◽  
Yılmaz Şahin ◽  
Murat Acar ◽  
...  
Keyword(s):  
Reverse Current ◽  
Electrical Characterization ◽  
Effect Of Temperature ◽  
Barrier Heights ◽  
Current Voltage ◽  
Temperature Dependences ◽  
Barrier Inhomogeneities ◽  
Current Voltage Characteristics ◽  
Increasing Temperature

AbstractA poly(phenoxy-imine)/p-silicon rectifying device was fabricated and the current-voltage characteristics of the device were examined as a function of temperature in the 40–300 K range. The temperature dependence of the main parameters, namely, the barrier height (Φb), ideality factor (η), reverse current (I0) and series resistance (Rs), were investigated. It was seen that the Φb and the I0 values of the device increased with increasing temperature, while the η and the Rs values decreased. The temperature dependences of the Φb and the η were interpreted by the assumption of a Gaussian distribution of the barrier heights arising from barrier inhomogeneities that prevailed at the interface of the poly(phenoxyimine)/p-silicon. From ln(I0/T2) vs. 1/ηT plot, the values of the activation energy (Ea) and Richardson constant (A*) were calculated as 0.324 eV and 2.84×10-7 A cm-2K-2, respectively. The experimental value of the Rs from the forward current-voltage plots decreased with an increase in the temperature.

Temperature-Dependent Electrical Characteristics of Ag Schottky Contacts to Differently Grown O-Polar Bulk ZnO

2013 ◽  
Vol 135 (1) ◽  
Author(s):  
Hogyoung Kim ◽  
Ahrum Sohn ◽  
Yunae Cho ◽  
Dong-Wook Kim
Keyword(s):  
Electron Transport ◽  
Electrical Properties ◽  
Schottky Contact ◽  
Thermionic Emission ◽  
Schottky Contacts ◽  
Current Transport ◽  
Electrical Characteristics ◽  
Temperature Dependent ◽  
Barrier Heights ◽  
Two Samples

The temperature-dependent electrical properties of Ag Schottky contacts to differently grown O-polar bulk ZnO single crystals were comparatively investigated in the temperature range of 100–300 K. Schottky contact to hydrothermal ZnO produced the higher barrier heights (lower ideality factors) than that of pressurized melt-grown ZnO. The modified Richardson plots for two samples produced the larger Richardson constant compared to the theoretical value of 32 A cm−2 K−2 for n-type ZnO, indicating that the inhomogeneous barrier height with the thermionic emission (TE) model could not explain the current transport. The conductive accumulation layers on the ZnO surfaces might not be removed effectively for two samples, which degraded the rectifying characteristics. The different electron transport characteristics between hydrothermal and pressurized melt-grown ZnO could be explained by the different degree of Ag-O formation at the interface.

Microstructure studies of tungsten silicide schottky contacts on Gaas

1987 ◽  
Vol 45 ◽  
pp. 328-329
Author(s):  
Yih-Cheng Shih ◽  
E. L. Wilkie
Keyword(s):  
Thermal Stability ◽  
Field Effect Transistors ◽  
Schottky Contact ◽  
Schottky Contacts ◽  
Excellent Thermal Stability ◽  
Barrier Heights ◽  
Gaas Substrates ◽  
Film Adhesion ◽  
Threshold Voltages ◽  
Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

Sign in / Sign up

Export Citation Format

Share Document