Deep level photothermal spectroscopy for characterizing Ni impurities in Si by a temperature dependent piezoelectric photothermal signal

2003 ◽  
Vol 74 (1) ◽  
pp. 340-342 ◽  
Author(s):  
S. Sato ◽  
A. Memon ◽  
A. Fukuyama ◽  
S. Tanaka ◽  
T. Ikari
Keyword(s):  
Deep Level ◽  
Photothermal Spectroscopy ◽  
Temperature Dependent

Improved SiO2/ 4H-SiC Interface Defect Density Using Forming Gas Annealing

2019 ◽  
Vol 963 ◽  
pp. 465-468
Author(s):  
Stephan Wirths ◽  
Giovanni Alfieri ◽  
Alyssa Prasmusinto ◽  
Andrei Mihaila ◽  
Lukas Kranz ◽  
...  
Keyword(s):  
Defect Density ◽  
Deep Level ◽  
Flat Band ◽  
Temperature Dependent ◽  
Mos Capacitors ◽  
Interface Defect ◽  
Before And After ◽  
Oxide Deposition ◽  
Transient Spectroscopy ◽  
Post Deposition

We investigated the influence of forming gas annealing (FGA) before and after oxide deposition on the SiO2/4H-SiC interface defect density (Dit). For MOS capacitors (MOSCAPs) that were processed using FGAs at temperatures above 1050°C, CV characterization revealed decreased flat band voltage shifts and stretch-out for different sweep directions and frequencies. Moreover, constant-capacitance deep level transient spectroscopy (CC-DLTS) was performed and showed Dit levels below 1012 cm-2eV-1 for post deposition FGA at 1200°C. Finally, lateral MOSFETs were fabricated to analyze the temperature-dependent threshold voltage (Vth) shift.

Transport Properties and Conduction Band Offset of n-ZnO/n-6H-SiC Heterostructures

2006 ◽  
Vol 957 ◽  
Author(s):  
Yahya Alivov ◽  
Xiao Bo ◽  
Fan Qian ◽  
Daniel Johnstone ◽  
Cole Litton ◽  
...  
Keyword(s):  
Conduction Band ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Band Offset ◽  
Measured Temperature ◽  
Temperature Dependent ◽  
Conduction Band Offset ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
Transient Spectroscopy

ABSTRACTThe conduction band offset of n-ZnO/n-6H-SiC heterostructures fabricated by rf-sputtered ZnO on commercial n-type 6H-SiC substrates has been measured. Temperature dependent current-voltage characteristics, photocapacitance, and deep level transient spectroscopy measurements showed the conduction band offsets to be 1.25 eV, 1.1 eV, and 1.22 eV, respectively.

Contact-Related Deep States in AI-GaInP/GaAs Interface

1993 ◽  
Vol 325 ◽  
Author(s):  
Z.C. Huang ◽  
C.R. Wie
Keyword(s):  
Deep Level ◽  
Schottky Diodes ◽  
Schottky Contact ◽  
Temperature Dependent ◽  
Current Voltage ◽  
Oxygen Contamination ◽  
Related Defect ◽  
Current Voltage Characteristics ◽  
Transient Spectroscopy ◽  
Recombination Current

AbstractDeep levels have been measured in molecular beam epitaxy grown Ga0.51In0.49P/GaAs heterostructure by double correlation deep level transient spectroscopy. Gold(Au) and Aluminum (Al) metals were used for Schottky contact. A contact-related hole trap with an activation energy of 0.50-0.75eV was observed at the A1/GaInP interface, but not at the Au/GaInP interface. To our knowledge, this contact-related trap has not been reported before. We attribute this trap to the oxygen contamination, or a vacancy-related defect, VIn or VGa. A new electron trap at 0.28eV was also observed in both Au- and Al-Schottky diodes. Its depth profile showed that it is a bulk trap in GaInP epilayer. The temperature dependent current-voltage characteristics (I-V-T) show a large interface recombination current at the GaInP surface due to the Al-contact. Concentration of the interface trap and the magnitude of recombination current are both reduced by a rapid thermal annealing at/or above 450°C after the aluminum deposition.

Postdeposition Thermal Annealing Influence on the Activation of the Cosputtered AlN-ZnO Films

2011 ◽  
Vol 687 ◽  
pp. 716-721
Author(s):  
Shiau Lu Yao ◽  
Jhen Dong Hong ◽  
Chung Yen Ho ◽  
Ching Ting Lee ◽  
Day Shan Liu
Keyword(s):  
Deep Level ◽  
Hole Concentration ◽  
Atomic Ratio ◽  
Shallow Donor ◽  
Annealed Sample ◽  
Zno Films ◽  
High Electron ◽  
Temperature Dependent ◽  
Acceptor Pair ◽  
Pl Spectra

Cosputtered aluminum nitride-zinc oxide (AlN-ZnO) films at a theoretical atomic ratio of 10% [Al / (Al + Zn) at.%] were postannealed at 450°C for 30 min under ambient nitrogen and vacuum, respectively. The activated impurities in these annealed samples were investigated through the room-temperature (RT) and low-temperature (LT) photoluminescence (PL) spectra as well as their temperature-dependent Hall-effect measurements. It was found that the donor-acceptor-pair (DAP) emission related to VZn-AlZn transition at 2.86 eV predominated over the defect-transition luminescence in the RTPL spectrum of the vacuum-annealed sample, for which possessed a high electron carrier concentration. With the help of the temperature-dependent Hall measurement, the shallow donor level corresponded to Al on Zn site (AlZn) was derived as EC – (51±4) meV. By contrast, the RTPL spectrum of the nitrogen-annealed AlN-ZnO cosputtered film, showing p-type conduction with a hole concentration of 1018 cm-3, was dominated by the VO-NO deep level emission approximately at 1.87 eV. The estimated acceptor level corresponded to the N on O site (NO) was EV + (149±6) meV. The binding energy and activation energy associated with the NO acceptor were also determined by the LTPL and temperature-dependent PL spectra.

scholarly journals Designing a Robust Kelvin Probe Setup Optimized for Long-Term Surface Photovoltage Acquisition

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 4068 ◽  
Author(s):  
Elke Beyreuther ◽  
Stefan Grafström ◽  
Lukas Eng
Keyword(s):  
Deep Level ◽  
Surface Photovoltage ◽  
Probe Design ◽  
Relaxation Processes ◽  
Kelvin Probe ◽  
Electrical Stability ◽  
Temperature Dependent ◽  
Transient Spectroscopy ◽  
Photoinduced Charge

We introduce a robust low-budget Kelvin probe design that is optimized for the long-term acquisition of surface photovoltage (SPV) data, especially developed for highly resistive systems, which exhibit—in contrast to conventional semiconductors—very slow photoinduced charge relaxation processes in the range of hours and days. The device provides convenient optical access to the sample, as well as high mechanical and electrical stability due to off-resonance operation, showing a noise band as narrow as 1 mV. Furthermore, the acquisition of temperature-dependent SPV transients necessary for SPV-based deep-level transient spectroscopy becomes easily possible. The performance of the instrument is demonstrated by recording long-term SPV transients of the ultra-slowly relaxing model oxide strontium titanate (SrTiO 3 ) over 20 h.

Comparative Study of Temperature Dependent Barrier Heights of Pd/ZnO Schottky Diodes Grown along Zn- and O-Faces

2012 ◽  
Vol 510-511 ◽  
pp. 265-270 ◽  
Author(s):  
M. Asghar ◽  
Khalid Mahmood ◽  
Adnan Ali ◽  
M.A. Hasan
Keyword(s):  
Barrier Height ◽  
Deep Level ◽  
Schottky Diodes ◽  
Thermionic Emission ◽  
Growth Conditions ◽  
Distribution Model ◽  
Metal Contacts ◽  
Temperature Dependent ◽  
Barrier Heights ◽  
Two Samples

In this study, the effect of polar face on Schottky barrier diodes has been investigated. Two samples of ZnO were grown hydrothermally under similar growth conditions. The Palladium (Pd) metal contacts of area 0.78 mm2were fabricated on both faces and were studied comprehensively using DLS-83 Deep Level Spectrometer over temperature range of 160K330K. The current-voltage (IV) measurements revealed that the ideality factor n and barrier height ϕBwere strongly temperature dependent for both faces (Zn and O-face) of ZnO, indicating that the thermionic emission is not the dominant process, which showed the inhomogenity in the barrier heights of grown samples. This barrier height inhomogenity was explained by applying Gaussian distribution model. The extrapolation of the linear ϕapverses n plot to n = 1 has given a homogeneous barrier height of approximately 0.88±0.01 eV and 0.76±0.01 eV for Zn and O-faces respectively. ϕapversus 1/T plot was drawn to obtain the values of mean barrier height for Zn and O-face (0.88±0.01 eV, 0.76±0.01 eV) and standard deviation (δs) (0.015±0.001 V, 0.014±0.001 V) at zero bais respectively. The value of δsfor the Zn-face is larger than O-face, showing that inhomogenity in the barrier heights is more in the sample grown along Zn-face as compared to the sample grown along O-face.

Annealing effect on the nonradiative carrier recombination in AlGaAs/GaAs investigated by a piezoelectric photothermal spectroscopy

2001 ◽  
Vol 692 ◽  
Author(s):  
Atsuhiko Fukuyama ◽  
Hiroaki Nagatomo ◽  
Yoshito Akashi ◽  
Tetsuo Ikari
Keyword(s):  
Deep Level ◽  
Band Gap Energy ◽  
Frequency Region ◽  
Annealing Effect ◽  
Photothermal Spectroscopy ◽  
Hetero Structure ◽  
Gap Energy ◽  
Carrier Recombination ◽  
Layer Region ◽  
Lower Frequency Region

AbstractElectron non-radiative recombination process of photoexcited carriers in as-grown and annealed n-Al0.2Ga0.8As/GaAs hetero-structure samples are investigated by using a piezoelectric photothermal spectroscopy (PPTS). The PPT signal above the band-gap energy of GaAs substrate decreased when the sample was annealed at 815°C. In the frequency dependent measurements, the deviations from 1/f linear function are clearly observed in the AlGaAs/GaAs samples. This critical deviation frequency was found to shift to the lower frequency region by annealing. Our experimental results are explained by assuming that the sample annealing generates an unknown deep level in AlGaAs epitaxial layer region and this level effectively traps the photoexcited carriers non-radiatively.

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