Electrical Study of Schottky Barriers on Cleaved InP and GaAs (110) Surfaces

1985 ◽  
Vol 54 ◽  
Author(s):  
N. Newman ◽  
M. van Schilfgaarde ◽  
T. Kendelewicz ◽  
W. E. Spicer
Keyword(s):  
Barrier Height ◽  
Ideality Factor ◽  
High Vacuum ◽  
Forward Bias ◽  
Thermionic Emission ◽  
Ultra High Vacuum ◽  
Leakage Currents ◽  
Current Voltage ◽  
Measuring Techniques

We have performed a systematic study of the electrical properties of a large number of metal/n-GaAs and metal/n-InP diodes. Diodes were fabricated on clean cleaved InP and GaAs (110) surfaces in ultra-high vacuum with in-situ metal deposition of Cr, Mn, Sn, Ni, Al, Pd, Cu, Ag and Au. Using current-voltage (I-V) and capacitance-voltage (C-V) measuring techniques, we were able to obtain very reliable and consistent determinations of the barrier height, θ/b, and ideality factor, n. All of the metal-semiconductor systems formed on lightly doped (< 5×1016/cm3) substrates were characterized by near-unity (1.05) ideality factors.The effects of doping on the electrical characteristics of the n-GaAs diodes were investigated. A decrease in the effective I-V barrier height, an increase in the ideality factor in forward bias and a strong voltage dependence on the thermionic emission currents in reverse bias were found for diodes formed on the more heavily doped samples. These changes are essentially metal-independent, but depend strongly on the doping of the substrate. The characterization (and elimination in some cases) of peripheral leakage currents from the thermionic emission current for the n-GaAs systems was found to be essential in obtaining consistent results in our work and in reinterpreting some of the prior work in the literature. The dominant leakage current in the GaAs diodes flows through a small area, low barrier at the periphery of the device and can be eliminated by mesa etching.

Laterally Inhomogeneous Barrier Height Analysis for Thermally Annealed CuNiTi/p-InP Contacts

2017 ◽  
Vol 890 ◽  
pp. 127-130
Author(s):  
Bahattin Abay
Keyword(s):  
Barrier Height ◽  
Thermal Annealing ◽  
Ideality Factor ◽  
Forward Bias ◽  
Thermionic Emission ◽  
Characteristic Parameters ◽  
Inp Substrate ◽  
Current Voltage ◽  
Positively Charged ◽  
Device Technology

The fabrication of thermally stable Schottky contacts with high barrier height (BH) to InP is one of the main challenges for InP-based device technology. CuNiTi/p-InP Schottky barrier diodes (SBDs) (25 dots) on p-InP substrate were fabricated by conventional vacuum deposition. Characteristic parameters such as BH and ideality factor (n) of as-deposited and annealed CuNiTi/p-InP diodes have been computed by thermionic emission (TE) theory from the forward-bias current-voltage (I-V) data, at room temperature and in dark. The value of BH and n varies from 0.452 to 0.631 eV and 1.172 to 2.815, respectively for the as-deposited SBDs. The results showed that characteristic parameters of CuNiTi/p-InP structures differ from one device to another even though they were identically prepared. Hence, to overcome these problems post thermal annealing was implemented since the annealing process can improve the interfacial quality as well as can induce a recrystallization of the gate metals. BH values for CuNiTi/p-InP SBDs have also varied from 0.765 to 0.804 eV, and ideality factor n from 1.161 to 1.253 after annealing at 500 °C for two minutes. As a result of the thermal annealing, it has been seen that the BH values of the annealed SBDs are larger than those of the as-deposited ones. A statistical study on the diode parameters has been made. The experimental BH and ideality factor distributions were fitted by a Gaussian distribution (GD) function. Lateral homogeneous BH (φhom.) values of 0.628 eV and 0.886 eV for the as-deposited and annealed CuNiTi/p-InP SBDs has been obtained from the φeff.-n plots by using Tung’s lateral inhomogeneity approach. An increment of 0.258 eV in the BH for the 500 °C annealing devices with respect to that of the as-deposited ones has been ascribed to the formation of the positively charged interface defects that electrically actives in the metal-semiconductor (MS) interface.

Majority Carrier Transport Across Semiconductor Grain Boundaries

1990 ◽  
Vol 209 ◽  
Author(s):  
S.F. Nelson ◽  
P.V. Evans ◽  
S.L. Sass ◽  
D.A. Smith
Keyword(s):  
Carrier Transport ◽  
High Vacuum ◽  
Thermionic Emission ◽  
Ultra High Vacuum ◽  
Defect States ◽  
Intrinsic Structure ◽  
Majority Carrier ◽  
Float Zone ◽  
Current Voltage ◽  
Misorientation Angles

AbstractMajority carrier transport measurements were made across the potential barriers at (100) twist boundaries in silicon. The bicrystals were prepared by hot-pressing single crystals of lightly doped float-zone material, under ultra-high vacuum conditions. The current - voltage measurements were analyzed using combined drift-diffusion and thermionic emission transport mechanisms, and incorporating some inhomogeneity in the charge distribution at the boundary. Evidence has been found for a small, Nd = 3 × 1010 cm−2, density of mono-energetic defect states near midgap, in bicrystals characterized by a variety of misorientation angles. This density is too small to result from the intrinsic structure of the boundary. In addition, no dependence was found on misorientation angle.

Fabrication and characteristics study of ITO/DBSA/PSS/PPY/Al SCHOTTKY junction diode

2014 ◽  
Vol 34 (5) ◽  
pp. 471-475 ◽  
Author(s):  
Periyannan Jayamurugan ◽  
Veerappa Gounder Ponnuswamy ◽  
Ramasamy Mariappan ◽  
Thaiyan Mahalingam ◽  
Yammani Venkat Subba Rao
Keyword(s):  
Band Gap ◽  
Ideality Factor ◽  
Indium Tin Oxide ◽  
Sulfonic Acid ◽  
Uv Spectroscopy ◽  
Forward Bias ◽  
Band Gap Energy ◽  
Current Voltage ◽  
Ito Glass

Abstract A water-dispersed dodecylbenzene sulfonic acid (DBSA)/poly (styrene sulfonic acid) (PSS)/polypyrrole (PPY) composite was prepared by an in situ chemical polymerization method. The prepared solution was spun on indium tin oxide (ITO) glass plates at different rates of 2000 and 3000 rpm. The optical band gap energy (Eg) was calculated by UV spectroscopy. The band gap of the composite thin films was found at 1.89 eV and 1.93 eV, respectively. A Fourier transform infrared (FTIR) spectrum confirms the presence of dopant and co-dopant in the structure. The diode parameters were calculated from current-voltage (I-V) characteristics and discussed. The I-V characteristics of the devices indicated behavior of a Schottky diode. The ideality factor, barrier height (ϕb) and saturation current were investigated. The ϕb was found to be 0.59 eV and 0.52 eV for 2000 rpm and 3000 rpm, respectively. The ideality factor was calculated from the slope of the linear region of the forward bias in the I-V curves and was found to be 6.4 and 13.5. The results of the present study reveal that the 2000 rpm coated ITO/DBSA/PSS/PPY/Al device showed better nonlinearity behavior than the 3000 rpm one.

scholarly journals Comparison of electrical properties of CuO/n-Si contacts with Cu/n-Si

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Reşit Özmenteş ◽  
Cabir Temirci
Keyword(s):  
Electrical Properties ◽  
Barrier Height ◽  
Ideality Factor ◽  
Series Resistance ◽  
Reference Sample ◽  
Forward Bias ◽  
Schottky Contact ◽  
Experimental Result ◽  
Current Voltage ◽  
Capacitance Voltage

AbstractIn this study, CuO/n-Si/Al heterojunction contacts were fabricated by thermal evaporation technique. Electrical characteristics of the samples were investigated with the current-voltage (I-V), capacitance-voltage/frequency (C-V/f), and conductance-voltage (G/V) measurements at room temperature. Also, Cu/n-Si/Al Schottky contact was produced as a reference sample to investigate the electrical properties of the samples. The values of ideality factor (n), barrier height (Φb) and series resistance (Rs) of the samples were calculated from the forward bias current-voltage (I-V) and reverse bias capacitance-voltage (C-V) characteristics. Also, for checking the consistency of the results, Cheung and Norde functions were used. The experimental result values of CuO/n-Si contact were compared with the values of the reference Cu/n-Si Schottky diode. It was observed that the values of the ideality factor and barrier height of the CuO/n-Si heterojunction were higher than those of the Cu/n-Si Schottky contact, while the series resistance was lower. Also, it has been observed that the value of capacitance decreased with increasing frequency and after a certain value of frequency it was almost constant. The ideality factor of CuO/n-Si/Al heterostructure is about 2.40 and so, it is not close to the ideal behavior.

Current-Voltage and Capacitance-Voltage Characteristics of Pd Schottky Diodes Fabricated on ZnO Grown along Zn- and O-Faces

2013 ◽  
Vol 313-314 ◽  
pp. 270-274
Author(s):  
M. Faisal ◽  
M. Asghar ◽  
Khalid Mahmood ◽  
Magnus Willander ◽  
O. Nur ◽  
...  
Keyword(s):  
Barrier Height ◽  
Ideality Factor ◽  
Doping Concentration ◽  
Series Resistance ◽  
Schottky Diodes ◽  
Thermionic Emission ◽  
Temperature Dependent ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Increasing Temperature

Temperature dependent current-voltage (I-V) and capacitance-voltage (C-V) measurements were utilized to understand the transport mechanism of Pd Schottky diodes fabricated on Zn- and O-faces of ZnO. From I-V measurements, in accordance with the thermionic emission mechanism theory, it was found that the series resistance Rsand the ideality factor n were strongly temperature dependent that decreased with increasing temperature for both the faces (Zn and O-face) of ZnO revealing that the thermionic emission is not the dominant process. The barrier height øB(I-V)increased with increasing temperature for both faces. The measured values of ideality factor, barrier height and series resistance for Zn- and O-faces at room temperature were 4.4, 0.60 eV, 217 Ω and 2.8, 0.49 eV, 251 Ω respectively. The capacitance-voltage (C–V) measurements were used to determine the doping concentration Nd, the built-in-potential Vbi, and the barrier height øB(C-V). The doping concentration was found to be decreased with increasing depth. The barrier height øB(C-V)calculated for O-polar and Zn-polar faces decreases with increasing temperature. The values of barrier height øB(C-V)determined from C-V measurements were found higher than the values of barrier height øB(I-V). Keeping in view the calculated values of ideality factor, barrier height, and series resistance shows that O-polar face is qualitatively better than Zn-polar face.

scholarly journals Electrical and Photoconductivity Properties of Al/CdFe2O4/p-Si/Al Photodiode

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Mehmet Çavaş ◽  
Fahrettin Yakuphanoglu ◽  
Savaş Kaya
Keyword(s):  
Barrier Height ◽  
Ideality Factor ◽  
Low Cost ◽  
Strong Dependence ◽  
Sol Gel ◽  
Thermionic Emission ◽  
Emission Model ◽  
Current Voltage ◽  
Coating Method ◽  
Low Cost Manufacturing

In the present study, we have investigated the effects of illumination intensity on the optical and electrical characteristics of the Al/CdFe2O4/p-Si/Al photodiode. A thin film of CdFe2O4 was fabricated using the sol-gel spin coating method that allows good thickness control and low-cost manufacturing as compared to alternative techniques. The current-voltage (I-V) of the Al/CdFe2O4/p-Si/Al photodiode was measured in the dark and under different illumination intensities. The photocurrent increased with higher luminous intensity and its sensitivity has a strong dependence on the reverse bias rising from 1.08⁎10-7 A under dark conditions to 6.11⁎10-4 A at 100 mW/cm2 of illumination. The parameters of the photodiode such as ideality factor and barrier height were calculated using the thermionic emission model. The ideality factor of the Al/CdFe2O4/p-Si/Al photodiode was found to be 4.4. The barrier height was found to be 0.88 eV. The capacitance-voltage (C-V) characteristics measured at different frequencies have strongly varied with frequency, decreasing with frequency. Consequently, the resulting interface density (Dit) value of the Al/CdFe2O4/p-Si/Al photodiode also decreased with higher frequency. Similarly, the fitted series resistance of the Al/CdFe2O4/p-Si/Al photodiode has declined with higher frequency.

Electrical Characteristics of n-Type Nanocrystalline FeSi2/Intrinsic Si/p-Type Si Heterojunctions Prepared by Facing-Targets Direct-Current Sputtering

2013 ◽  
Vol 446-447 ◽  
pp. 88-92
Author(s):  
Nathaporn Promros ◽  
Suguru Funasaki ◽  
Ryūhei Iwasaki ◽  
Tsuyoshi Yoshitake
Keyword(s):  
Barrier Height ◽  
Ideality Factor ◽  
Low Temperatures ◽  
Series Resistance ◽  
Linear Part ◽  
Thermionic Emission ◽  
Straight Line ◽  
Current Voltage ◽  
P Type ◽  
Direct Current Sputtering

n-Type nanocrystalline FeSi2/intrinsic Si/p-type Si heterojunctions were prepared by FTDCS. In order to estimate their diode parameters such as ideality factor, barrier height and series resistance, their current-voltage characteristics were measured in the temperature range from 300 to 77 K and analyzed on the basis of thermionic emission theory and Cheungs method. Based on thermionic emission theory, the ideality factor was calculated from the slope of the linear part from the forward lnJ-V characteristics. The barrier height was calculated once the saturation current density was derived from the straight line intercept of lnJ-V plot at a zero voltage. The obtained results exhibit an increase of ideality factor and a decrease of barrier height at low temperatures, which might be owing to inhomogeneity of material and non-uniformity of charge at the interface. Based on Cheungs method, the ideality factor and barrier height were estimated from y-axis intercept of dV/d (lnJ)J plot and y-axis intercept of H(J)J plot, respectively. The series resistance was analyzed from the slopes of dV/d (lnJ)J and H(J)J plots. The values of ideality factor and barrier height obtained from this method are in agreement with those obtained from the thermionic emission theory. The obtained series resistances from dV/d (lnJ)J and H(J)J plots, which were approximately equal to each others, were increased as the temperature decreased. This result should be owing to the increased ideality factor and remarkably reduced carrier concentrations at low temperatures.

Mechanism of Carrier Transport in n-Type β-FeSi2/Intrinsic Si/p-Type Si Heterojunctions

2015 ◽  
Vol 1119 ◽  
pp. 189-193
Author(s):  
Nathaporn Promros ◽  
Motoki Takahara ◽  
Ryuji Baba ◽  
Tarek M. Mostafa ◽  
Mahmoud Shaban ◽  
...  
Keyword(s):  
Ideality Factor ◽  
Carrier Transport ◽  
Linear Part ◽  
Forward Bias ◽  
Thermionic Emission ◽  
Forward Bias Voltage ◽  
Space Charge Limit ◽  
Current Voltage ◽  
P Type ◽  
Direct Current Sputtering

Preparation of n-type β-FeSi2/intrinsic Si/p-type Si heterojunctions was accomplished by facing-target direct-current sputtering (FTDCS) and measuring their current-voltage characteristic curves at low temperatures ranging from 300 K down to 50 K. A mechanism of carrier transport in the fabricated heterojunctions was investigated based on thermionic emission theory. According to this theory, the ideality factor was calculated from the slope of the linear part of the forward lnJ-V plot. The ideality factor was 1.12 at 300 K and increased to 1.99 at 225 K. The estimated ideality factor implied that a recombination process was the predominant mechanism of carrier transport. When the temperatures decreased below 225 K, the ideality factor was estimated to be higher than two and parameter A was estimated to be constant. The obtained results implied that the mechanism of carrier transport was governed by a trap-assisted multi-step tunneling process. At high forward bias voltage, the predominant mechanism of carrier transport was changed into a space charge limit current process.

THE EFFECT OF NANO AND MICRO POROSITY ON THE SCHOTTKY BARRIER HEIGHT AND IDEALITY FACTOR IN THE I–V CHARACTERISTICS OF PtSi/p-Si IR DETECTOR

2009 ◽  
Vol 23 (05) ◽  
pp. 765-771
Author(s):  
H. ESHGHI ◽  
M. MOHAMMADI
Keyword(s):  
Schottky Barrier ◽  
Barrier Height ◽  
Ideality Factor ◽  
Schottky Barrier Height ◽  
Thermionic Emission ◽  
Ir Detector ◽  
Current Voltage ◽  
Two Samples ◽  
P Type ◽  
Silicon Interface

In this paper, the effect of porosity on reverse bias current–voltage characteristics of PtSi/por - Si (p-type) IR detector as a function of temperature is investigated. Our experimental data for two samples with different porosities (50% and 10%) at 300 K and 77 K are reported by Raissi et al.1 These data indicates a breakdown-like behavior. Our analytical model is based on hole thermionic emission with large ideality factor (n ≈ 200). Our calculations show that at each temperature, the Schottky barrier height, as well as the ideality factor, in sample with 10% porosity is bigger than that of 50%. These variations could be due to band gap variations of Si size effect using quantum dot model, and the presence of the relatively high (~1015 cm-2 eV-1) density of states at the silicide/por-silicon interface, respectively.

Diode Parameters of Mesa Structural n-Type Nanocrystalline FeSi2/p-Type Si Heterojunctions Prepared by Lift-Off Photolithography

2015 ◽  
Vol 1103 ◽  
pp. 91-96
Author(s):  
Nathaporn Promros ◽  
Suguru Funasaki ◽  
Motoki Takahara ◽  
Ryūhei Iwasaki ◽  
Mahmoud Shaban ◽  
...  
Keyword(s):  
Barrier Height ◽  
Ideality Factor ◽  
Low Temperatures ◽  
Series Resistance ◽  
Thermionic Emission ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
Lift Off ◽  
P Type ◽  
Photolithography Process

Mesa structural n-type nanocrystalline-FeSi2/p-type Si heterojunctions were successfully fabricated by a lift-off technique combined with a photolithography process. Their current-voltage characteristics were measured at low temperatures range from 300 K down to 60 K. We estimated their diode parameters such as ideality factor, barrier height and series resistance based on the thermionic emission theory and Cheung’s method. From the estimation by the thermionic emission theory, the obtained results show an increase of ideality factor and a decrease of barrier height at low temperatures. The estimation by Cheung’s method shows that the values of ideality factor and barrier height are in agreement with those obtained from the thermionic emission theory. The obtained series resistances from dV/d (lnJ)-J and H(J)-J plots, which are approximately equal to each others, are increased at low temperatures.

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