Ion Implanted p+/n Diodes: Post-Implantation Annealing in a Silane Ambient in a Cold-Wall Low-Pressure CVD Reactor

2006 ◽  
Vol 527-529 ◽  
pp. 819-822
Author(s):  
Fabio Bergamini ◽  
Shailaja P. Rao ◽  
Antonella Poggi ◽  
Fabrizio Tamarri ◽  
Stephen E. Saddow ◽  
...  

This work reports the realization and characterization of 4H-SiC p+/n diodes with the p+ anodes made by Al+ ion implantation at 400°C and post-implantation annealing in silane ambient in a cold-wall low-pressure CVD reactor. The Al depth profile was almost box shaped with a height of 6×1019 cm-3 and a depth of 160 nm. Implant anneals were performed in the temperature range from 1600°C to 1700°C. As the annealing temperature was increased, the silane flow rate was also increased. This annealing process yields a smooth surface with a roughness of the implanted area of 1.7 - 5.3 nm with increasing annealing temperature. The resistivity of the implanted layer, measured at room temperature, decreased for increasing annealing temperatures with a minimum value of 1.4 0-cm measured for the sample annealed at 1700°C. Considering only the current-voltage characteristic of a diode that could be modeled as an abrupt p/n junction within the frame of the Shockley theory, the diode process yield and the diode leakage current decreased, respectively, from 93% to 47% and from 2×10-7 Acm-2 to 1×10-8 Acm-2 at 100 V reverse bias, for increasing post implantation annealing temperature.

2012 ◽  
Vol 1394 ◽  
Author(s):  
Christine Berven ◽  
Lorena Sanchez ◽  
Sirisha Chava ◽  
Hannah Marie Young ◽  
Joseph Dick ◽  
...  

ABSTRACTWe report apparent robust doping of ZnO and MgxZn1-xO (x ∼20%) nanoparticle films by annealing in hydrogen gas. The annealing was done at sequentially higher temperatures from about 20 °C to 140 °C. The effect of the annealing was determined by comparing current-voltage measurements of the samples at room-temperature and in vacuum after each annealing cycle.The nanoparticles were grown using an aqueous solution and heating process that created thinfilms of ZnO or MgZnO nanoparticles with diameters of about 30 nm. When exposed to hydrogen gas at room-temperature or after annealing at temperatures up to about 100 °C, no measureable changes to the room-temperature vacuum conductivity of the films was observed. However, when the samples were annealed at temperatures above 100 °C, an appreciable robust increase in the room-temperature conductance in vacuum occurred. Annealing at the maximum temperature (∼135-140 °C) resulted in about a factor of about twenty increase in the conductivity. Furthermore, the ratio of the conductance of the ZnO and MgZnO nanoparticle films while being annealed to their conductance at room-temperature were found to increase and then decrease for increasing annealing temperatures. Maximum changes of about five-fold and seven-fold for the MgZnO and ZnO samples, respectively, were found to occur at temperatures just below the annealing temperature threshold for the onset of the robust hydrogen gas doping. Comparisons of these results to other work on bulk ZnO and MgZnO films and reasons for this behavior will be discussed.


2021 ◽  
Author(s):  
Mayyada Muttar Fdhala ◽  
◽  
Ayser A. Hemed ◽  
Ramiz A. Al-Ansari ◽  
Raad M. Al-Haddad ◽  
...  

Schottky Diode (SD) Al/a-Se/Au as a solar cell (SC) was prepared by thermal evaporation technique (TET) on glass thin slide as a substrate under vacuum (10!" mbar). The Schottky Barrier (SB) have been prepared with different thicknesses (300, 500 and 700) nm in room temperature and (343) K annealing temperature. The current-voltage (IV) physical properties of the SB have got rectification properties and approved as a SC. This cell is developed with increased annealing temperatures and thickness of layers of SD. Experience under lighting shows good efficiency (η), which increased linearly with both thickness and annealing temperatures from (0.0318% to 4.064%) and from (0.0318% to 0.4778%). This is for three values of lighting power density (160, 230, 400) 𝑚𝑊/𝑐𝑚# in which the behave is similar. The best efficiency obtained in this work was (15.286)% at a power density of 400 𝑚𝑊/𝑐𝑚# , with thickness 700nm and 343K annealing temperature. Also (12.407)% at 230 𝑚𝑊/𝑐𝑚#, with thickness 500nm for the same annealing temperature.


2011 ◽  
Vol 110-116 ◽  
pp. 1094-1098
Author(s):  
Haleh Kangarlou ◽  
Mehdi Bahrami Gharahasanloo ◽  
Akbar Abdi Saray ◽  
Reza Mohammadi Gharabagh

Ti films of same thickness, and near normal deposition angle, and same deposition rate were deposited on glass substrates, at room temperature, under UHV conditions. Different annealing temperatures as 393K, 493K and 593K with uniform 8 cm3/sec, oxygen flow, were used for producing titanium oxide layers. Their nanostructures were determined by AFM and XRD methods. Roughness of the films changed due to annealing process. The gettering property of Ti and annealing temperature can play an important role in the nanostructure of the films.


2018 ◽  
Vol 924 ◽  
pp. 333-338 ◽  
Author(s):  
Roberta Nipoti ◽  
Alberto Carnera ◽  
Giovanni Alfieri ◽  
Lukas Kranz

The electrical activation of 1×1020cm-3implanted Al in 4H-SiC has been studied in the temperature range 1500 - 1950 °C by the analysis of the sheet resistance of the Al implanted layers, as measured at room temperature. The minimum annealing time for reaching stationary electrical at fixed annealing temperature has been found. The samples with stationary electrical activation have been used to estimate the thermal activation energy for the electrical activation of the implanted Al.


Author(s):  
I.A. Tarasov ◽  
M.V. Rautskii ◽  
I.A. Yakovlev ◽  
M.N. Volochaev

AbstractSelf-assembled growth of α-FeSi_2 nanocrystal ensembles on gold-activated and gold-free Si(001) surface by molecular beam epitaxy is reported. The microstructure and basic orientation relationship (OR) between the silicide nanocrystals and silicon substrate were analysed. The study reveals that utilisation of the gold as catalyst regulates the preferable OR of the nanocrystals with silicon and their habitus. It is shown that electron transport from α-FeSi2 phase into p-Si(001) can be tuned by the formation of (001)—or (111)—textured α-FeSi2 nanocrystals ensembles. A current-voltage characteristic of the structures with different preferable epitaxial alignment (α-FeSi_2(001)/Si(100) and α-FeSi_2(111)/Si(100)) shows good linearity at room temperature. However, it becomes non-linear at different temperatures for different ORs due to different Schottky barrier height governed by a particular epitaxial alignment of the α-FeSi_2/ p -Si interfaces.


2017 ◽  
Vol 31 (02) ◽  
pp. 1750006 ◽  
Author(s):  
Mohammad Hossein Ghorbani ◽  
Abdol Mahmood Davarpanah

Manganese oxides are of more interest to researchers because of their ability as catalysts and lithium batteries. In this research, MnO2nanowires with diameter about 45 nm were synthesized by sol–gel method at room temperature (RT). Effect of increasing the annealing temperature from 400[Formula: see text]C to 600[Formula: see text]C on crystalline structure of nanostructure were studied and average crystallite size was estimated about 22 nm. X-ray Diffraction (XRD) method, Energy-Dispersive X-ray Diffraction (EDXD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) were used to characterize the nanowires of MnO2.


1998 ◽  
Vol 513 ◽  
Author(s):  
B. K. Lee ◽  
A. J. Steckl ◽  
J. M. Zavada ◽  
R. G. Wilson

ABSTRACTThe effect of the incorporation and annealing of deuterium in 3C-SiC on its photoluninescence is reported. A 3C-SiC crystal has been implanted with 100 keV deuterium and subsequently annealed at temperatures between 1015 °C and 1220 °C for 1 to 5 minutes. SIMS depth profiles indicate hydrogen is strongly trapped by defects generated through ion bombardment, but a gradual damage repairing occurs during annealing. Photoluminescence was measured with 488 nm Ar laser excitation for sample temperatures from 89 K to 400 K. The PL peak wavelength of 540 nm at room temperature has shifted to 538 nm at 89 K. The peak PL intensity decreases with measurement temperature while its full width at half maximum (FWHM) exhibits an increasing trend. PL data were taken at five annealing stages. The post-implantation peak PL intensity and its integrated area increase initially with annealing temperature and time. After the final annealing at 1218 °C for 2 minute, PL intensity and its integrated area exhibit a decrease in level.


2012 ◽  
Vol 717-720 ◽  
pp. 817-820
Author(s):  
Roberta Nipoti ◽  
A. Nath ◽  
Mulpuri V. Rao ◽  
Anders Hallén ◽  
F. Mancarella ◽  
...  

A post implantation microwave annealing technique has been applied for the electrical activation of Al+ implanted ions in semi-insulating 4H-SiC. The annealing temperatures have been 2000-2100°C. The implanted Al concentration has varied from 5 x 1019 to 8 x 1020 cm-3. A minimum resistivity of 2 x 10-2 Ω∙cm and about 70% electrical activation of the implanted Al has been measured at room temperature for an implanted Al concentration of 8 x 1020 cm-3 and a microwave annealing at 2100°C for 30 s.


2005 ◽  
Vol 19 (15n17) ◽  
pp. 2804-2810 ◽  
Author(s):  
LEI MIAO ◽  
SAKAE TANEMURA ◽  
YASUHIKO HAYASHI ◽  
MASAKI TANEMURA ◽  
RONGPING WANG ◽  
...  

ZnO nanobamboos and nanowires with diameters of 10–30 nm and lengths of 2–4 μm have been prepared by laser ablation in vacuum with precisely controlled pressure, growth and post-annealing temperature. XRD results show the annealed sample is hexagonal ZnO . Low-magnified TEM observation reveals the annealed sample includes ZnO nanobamboos and nanowires. High resolution TEM image and electron diffraction pattern confirm that the structure of ZnO nanobamboo is regular stacking of Zn and O layers with high crystal quality. The growth direction is determined as along [001] direction (c axis). TEM observations confirm that the formation of bamboo-shape ZnO is due to the stacking fault and cleavage. The bundle of those stacking faults seems to be the origin of the black contrast at the nodes. The uniformity of chemical composition for the nanobamboos is identified by EDS profiles. A strong-narrow UV band centred at 390 nm and a weak-broad green band centred at 515 nm are observed at room temperature in the PL spectrum recorded from the annealed ZnO nanobamboos and nanowires.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
H. Abdullah ◽  
S. Habibi

CuInSe2(CIS) thin films are successfully prepared by electron beam evaporation. Pure Cu, In, and Se powders were mixed and ground in a grinder and made into a pellet. The pallets were deposited via electron beam evaporation on FTO substrates and were varied by varying the annealing temperatures, at room temperature, 250°C, 300°C, and 350°C. Samples were analysed by X-ray diffractometry (XRD) for crystallinity and field-emission scanning electron microscopy (FESEM) for grain size and thickness. I-V measurements were used to measure the efficiency of the CuInSe2/ZnS solar cells. XRD results show that the crystallinity of the films improved as the temperature was increased. The temperature dependence of crystallinity indicates polycrystalline behaviour in the CuInSe2films with (1 1 1), (2 2 0)/(2 0 4), and (3 1 2)/(1 1 6) planes at 27°, 45°, and 53°, respectively. FESEM images show the homogeneity of the CuInSe2formed. I-V measurements indicated that higher annealing temperatures increase the efficiency of CuInSe2solar cells from approximately 0.99% for the as-deposited films to 1.12% for the annealed films. Hence, we can conclude that the overall cell performance is strongly dependent on the annealing temperature.


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