Electrical Properties of Ultra Shallow p Junction on n type Si Wafer Using Decaborane Ion Implantation

2001 ◽  
Vol 686 ◽  
Author(s):  
Jae-Hoon Song ◽  
Duck-Kyun Choi ◽  
Min-Seok Oh ◽  
Won-Kook Choi

AbstractThe junction depth should be less than 0.05 microns to fabricate sub 0.1 micron devices. This requires implanting boron with energy of less than 1 keV. One drawback in a low energy ion source is low throughput due to low ion beam current. At present, boron known for a major p-type dopant for PMOSFET has problem to easily diffuse into Si wafer even in rapid thermal processing by high diffusivity. To resolve this problem, decaborane (B10H14) molecules are implanted to make p+/n junction on n-type Si wafers for low-energy boron dopant source. Ionized decaborane is accelerated at 1∼10 kV and implanted up to dosages from 1×1012/cm2 to 5×1013/cm2. Afterwards, Decaborane implanted Si wafers were post-annealed for 10 sec at 800, 900 and 1000°C, respectively. From RBS results on as-implanted n-type Si wafer implanted at 5 kV, it is observed there are amorphous Si layers with 4 nm in depth and boron ions are implanted up to 1∼5 nm in depth from SIMS analysis. The electrical properties of these p-n junctions are 127∼130 ω/sq. as sheet resistance, +0.3 V turn-on voltage and −1.1 V breakdown voltage obtained from I-V measurement.

2000 ◽  
Vol 610 ◽  
Author(s):  
Maria A. Albano ◽  
Vijay Babaram ◽  
John M. Poate ◽  
Marek Sosnowski ◽  
Dale C. Jacobson

AbstractFormation of p-type shallow junctions for future generations of Si devices will require ion implantation of B at very low energies (< 1 keV). An alternative to implantation of monomer ions at very low energy is implantation of large molecular ions at a higher energy. In an ion beam of decaborane (B10H14) each of the B atoms carries only 9% of the ion kinetic energy. We have examined ionization properties of decaborane and built an experimental ion source and an implantation apparatus with magnetic mass analysis. Analyzed decaborane ion beams with energies from 2 to 10 keV and beam currents of several microamperes were obtained. Si samples were implanted with decaborane ions and the implanted dose measured by current integration was compared with B content obtained by nuclear reaction analysis. Experiments with electrostatic beam deflection show that the large ions survive the transport in the implanter environment and that neutralization is negligible. During implantation, the retained B dose is reduced in comparison with the nominal implanted dose due to sputtering. Dose loss is greater at 200 eV compared to 500 eV. The properties of decaborane ion beams and the prospects of using them for shallow implantation of B into Si are discussed.


2005 ◽  
Vol 492 (1-2) ◽  
pp. 203-206 ◽  
Author(s):  
Zhi Yan ◽  
Zhi Tang Song ◽  
Wei Li Liu ◽  
Qing Wan ◽  
Fu Min Zhang ◽  
...  

In s.i.m.s. the sample surface is ion bombarded and the emitted secondary ions are mass analysed. When used in the static mode with very low primary ion beam current densities (10 -11 A/mm 2 ), the technique analyses the outermost atomic layers with the following advantages (Benninghoven 1973, I975): the structural—chemical nature of the surface may be deduced from the masses of the ejected ionized clusters of atoms; detection of hydrogen and its compounds is possible; sensitivity is extremely high (10 -6 monolayer) for a number of elements. Composition profiles are obtained by increasing the primary beam current density (dynamic mode) or by combining the technique in the static mode with ion beam machining with a separate, more powerful ion source. The application of static s.i.m.s. in metallurgy has been explored by analysing a variety of alloy surfaces after fabrication procedures in relation to surface quality and subsequent performance. In a copper—silver eutectic alloy braze it was found that the composition of the solid surface depended markedly on its pretreatment. Generally there was a surface enrichment of copper relative to silver in melting processes while sawing and polishing enriched the surface in silver


Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 508 ◽  
Author(s):  
Stanislav Tiagulskyi ◽  
Roman Yatskiv ◽  
Hana Faitová ◽  
Šárka Kučerová ◽  
David Roesel ◽  
...  

We study the effect of thermal annealing on the electrical properties of the nanoscale p-n heterojunctions based on single n-type ZnO nanorods on p-type GaN substrates. The ZnO nanorods are prepared by chemical bath deposition on both plain GaN substrates and on the substrates locally patterned by focused ion beam lithography. Electrical properties of single nanorod heterojunctions are measured with a nanoprobe in the vacuum chamber of a scanning electron microscope. The focused ion beam lithography provides a uniform nucleation of ZnO, which results in a uniform growth of ZnO nanorods. The specific configuration of the interface between the ZnO nanorods and GaN substrate created by the focused ion beam suppresses the surface leakage current and improves the current-voltage characteristics. Further improvement of the electrical characteristics is achieved by annealing of the structures in nitrogen, which limits the defect-mediated leakage current and increases the carrier injection efficiency.


1995 ◽  
Vol 13 (6) ◽  
pp. 2836-2842 ◽  
Author(s):  
Y.‐W. Kim ◽  
I. Petrov ◽  
H. Ito ◽  
J. E. Greene

1999 ◽  
Vol 581 ◽  
Author(s):  
X. T. Zhou ◽  
H. Y. Peng ◽  
N. G. Shang ◽  
N. Wang ◽  
I. Bello ◽  
...  

ABSTRACTComposite nanowires with typical diameters of 30-100nm, which consisted of Si, β-SiC, amorphous carbon were converted from Si nanowires by ion beam deposition. The Si nanorods were exposed to broad low energy ion beams. The low energy hydrocarbon, argon and hydrogen ions, generated in a Kaufman ion source, reacted with Si nanowires and formed the composite nanowires. It has been assumed that the reaction pathway to form the composite nanowires were driven by both thermal diffusion and kinetic energic of interacting particles.


2000 ◽  
Vol 648 ◽  
Author(s):  
X.Q. Cheng ◽  
H.N. Zhu ◽  
B.X. Liu

AbstractFractal pattern evolution of NiSi2 grains on a Si surface was induced by high current pulsed Ni ion implantation into Si wafer using metal vapor vacuum arc ion source. The fractal dimension of the patterns was found to correlate with the temperature rise of the Si substrate caused by the implanting Ni ion beam. With increasing of the substrate temperature, the fractal dimensions were determined to increase from less than 1.64, to beyond the percolation threshold of 1.88, and eventually up to 2.0, corresponding to a uniform layer with fine NiSi2 grains. The growth kinetics of the observed surface fractals was also discussed in terms of a special launching mechanism of the pulsed Ni ion beam into the Si substrate.


Radiocarbon ◽  
2010 ◽  
Vol 52 (2) ◽  
pp. 310-318 ◽  
Author(s):  
Yusuke Yokoyama ◽  
Mamito Koizumi ◽  
Hiroyuki Matsuzaki ◽  
Yosuke Miyairi ◽  
Naohiko Ohkouchi

We have developed accelerator mass spectrometry (AMS) measurement techniques for ultra small-size samples ranging from 0.01 to 0.10 mg C with a new type of MC-SNICS ion source system. We can generate 4 times higher ion beam current intensity for ultra-small samples by optimization of graphite position in the target holder with the new ionizer geometry. CO2 gas graphitized in the newly developed vacuum line is pressed to a depth of 1.5 mm from the front of the target holder. This is much deeper than the previous position at 0.35 mm depth. We measured 12C4+ beam currents generated by small standards and ion beam currents (15–30 μA) from the targets in optimized position, lasting 20 min for 0.01 mg C and 65 min for 0.10 mg C. We observed that the measured 14C/12C ratios are unaffected by the difference of ion beam currents ranging from 5 to 30 μA, enabling measurement of ultra-small samples with high precision. Examination of the background samples revealed 1.1 μg of modern and 1 μg of dead carbon contaminations during target graphite preparation. We make corrections for the contamination from both the modern and background components. Reduction of the contamination is necessary for conducting more accurate measurement.


Sign in / Sign up

Export Citation Format

Share Document