Silicided Shallow Junction Formation Using Ion Implantation and Thermal Annealing

1988 ◽  
Vol 128 ◽  
Author(s):  
Leonard M. Rubin ◽  
N. Herbots ◽  
D. Hoffman ◽  
D. Ma
Keyword(s):  
Ion Implantation ◽  
Thermal Annealing ◽  
Ion Beam ◽  
Thermal Reaction ◽  
Titanium Silicide ◽  
Native Oxide ◽  
Boron Implantation ◽  
Sputter Deposited ◽  
Mass Spectometry ◽  
And Control

ABSTRACTThe combination of arsenic and boron implantation with rapid thermal annealing (RTA) has been investigated to form shallow p-n junctions under a titanium silicide (TiSi2) metallization. The use of TiSi2 as a connection material can lead to the destruction of the junction if the kinetics of silicidation and doping are not well controlled. The purpose of this study is to better understand and control these kinetics, using far-from equilibrium processing such as ion implantation and RTA. The structures were characterized by Rutherford Backscattering Spectometry (RBS) for arsenic and silicide profiling, Secondary Ion Mass Spectometry (SIMS) for boron profiling, Scanning Electron Microscopy (SEM), and electrical sheet resistance measurements. Two procedures were investigated. Both involved the thermal reaction of Ti thin films, sputter-deposited with thicknesses ranging between 40 and 80 nm. In the first experiment, the as-deposited films were implanted with either 115 keV arsenic or 28 keV boron to form the junction, disperse the native oxide, and ion beam mix the Ti and Si. The films were then subjected to an RTA at 750°C for 15 to 60 seconds, which leads to TiSi2 formation in unimplanted films. Implantation was found to actually prevent TiSi2 formation. Ion transport calculations indicated that dopant pile-up at the interface might inhibit silicidation while higher energies and larger implant doses can more effectively ion beam mix Ti and Si. A more attractive solution consists of first forming TiSi2 from the as-deposited Ti by RTA, and then implanting to form the junction. This resulted in better control of the junction thickness. A sharp increase in the TiSi2 resistivity was found after implantation but the original value could be restored by a second RTA. This RTA also electrically activated the dopants and recrystallized the junction. The material properties of Ti/Si and TiSi2/Si under ion bombardment, RTA, doping, and conventional furnace annealing will be discussed.

scholarly journals Ion Beam Synthesis Of Cds, ZnS, And PbS Compound Semiconductor Nanocrystals

1997 ◽  
Vol 504 ◽  
Author(s):  
C. W. White ◽  
J. D. Budai ◽  
A. L. Meldrum ◽  
S. P. Withrow ◽  
R. A. Zuhr ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Thermal Annealing ◽  
Ion Beam ◽  
Semiconductor Nanocrystals ◽  
Compound Semiconductor ◽  
Size Distributions ◽  
Pbs Nanocrystals ◽  
Ion Beam Synthesis ◽  
The Matrix

ABSTRACTSequential ion implantation followed by thermal annealing has been used to form encapsulated CdS, ZnS, and PbS nanocrystals in SiO2 and Al2O3 matrices. In SiO2, nanoparticles are nearly spherical and randomly oriented, and ZnS and PbS nanocrystals exhibit bimodal size distributions. In Al2O3, nanoparticles are facetted and oriented with respect to the matrix. Initial photoluminescence (PL) results are presented.

High-Dose Titanium Ion Implantation into Epitaxial Si/3C-SiC/Si Layer Systems for Electrical Contact Formation

2000 ◽  
Vol 622 ◽  
Author(s):  
Jörg K.N. Lindner ◽  
Stephanie Wenzel ◽  
Bernd Stritzker
Keyword(s):  
Surface Layer ◽  
Solid State ◽  
Ion Implantation ◽  
Silicon Substrate ◽  
Ion Beam ◽  
Electrical Contact ◽  
Titanium Silicide ◽  
Solid State Reactions ◽  
High Dose ◽  
Homogeneous Surface

ABSTRACTHigh-dose titanium implantations have been performed into ion beam synthesized heteroepitaxial layer systems of Si/3C-SiC/Si(100) in order to study the formation of titanium silicide layers in the silicon top layer. The structure and composition of layers was analysed using RBS, XRD, XTEM and EFTEM. The sputtering rates of 180 keV Ti ions were determined using the lower SiC/Si interface as a marker. A homogeneous surface layer with the stoichiometry of TiSi2 was formed by a nearly stoichiometric implantation and subsequent annealing. The formation of more metal-rich silicides was observed at doses where the peak Ti concentration largely exceeds the TiSi2 stoichiometry and where the total amount of Ti atoms in the top layer is greater than the amount needed to convert the entire Si top layer into TiSi2. Under these conditions, strong solid state reactions of the implanted Ti atoms with the buried SiC layer and the silicon substrate are observed.

Formation of Titanium Silicide by Multiple Arsenic Implantations and Ion Beam Mixing

1991 ◽  
Vol 224 ◽  
Author(s):  
Po-Ching Chen ◽  
Jian-Yang Lin ◽  
Huey-Liang Hwang
Keyword(s):  
Electron Diffraction ◽  
Sheet Resistance ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
Titanium Silicide ◽  
Mixing Conditions ◽  
Cross Sectional ◽  
Ion Beam Mixing ◽  
Post Annealing

AbstractTitanium silicide was formed on the top of Si wafers by arsenic ion beam mixing and rapid thermal annealing. Three different arsenic-ion mixing conditions were examined in this work. The sheet resistance, residue As concentration post annealing and TiSi2 phase were characterized by using the* four-point probe, RBS and electron diffraction, respectively. TiSi2 of C54 phase was identified in the doubly implanted samples. The thickness of the Ti silicide and the TiSi2/Si interface were observed by the cross-sectional TEM.

Integrated Processinyg of Silicided Shallow Junctions using Rapid Thermal Annealing Prior to Dopant Activation

1989 ◽  
Vol 146 ◽  
Author(s):  
Leonard Rubin ◽  
Nicole Herbots ◽  
JoAnne Gutierrez ◽  
David Hoffman ◽  
Di Ma
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Titanium Silicide ◽  
Silicon Substrates ◽  
Sheet Resistivity ◽  
Furnace Annealing ◽  
Dopant Activation ◽  
Silicide Layer ◽  
Low Leakage ◽  
Sputter Deposited

ABSTRACTA method for producing shallow silicided diodes for MOS devices (with junction depths of about 0.1 µm), by implanting after forming the silicide layer was investigated. The key to this integrated process is the use of rapid thermal annealing (RTA) to activate the dopants in the silicon, so that there is very little thermal broadening of the implant distribution. Self-aligned titanium silicide (TiSi2) films with thicknesses ranging from 40 to 80 nm were grown by RTA of sputter deposited titanium films on silicon substrates. After forming the TiSi2, arsenic and boron were implanted. A second RTA step was used after implantation to activate these dopants. It was found that implanting either dopant caused a sharp increase in the sheet resistivity of the TiSi2. The resistivity can be easily restored to its original value (about 18 µΩ-cm) by a post implant RTA anneal. RBS analysis showed that arsenic diffuses rapidly in the TiSi2 during RTA at temperatures as low as 600°C. SIMS data indicated that boron was not mobile up to temperatures of 900°C, possibly because it forms a compound with the titanium which precipitates in the TiSi 2. Coalescence of TiSi2 occurs during post implant furnace annealing, leading to an increase in the sheet resistivity. The amount of coalescence depends on the film thickness, but not on whether or not the film had been subject to implantation. Spreading resistance profiling data showed that both arsenic and boron diffused into the TiSi2 during furnace annealing, reducing the surface concentrations of dopant at the TiSi2/Si interface. Both N+/P and P+/N diodes formed by this technique exhibited low leakage currents after the second RTA anneal. This is attributed to removal of the implant damage by the RTA. In summary, the second RTA serves the dual purpose of removing implant damage in the TiSi2 and creating the shallow junction by dopant activation.

Doping properties of the Ion-Beam-Sputtered SiGe Film

1996 ◽  
Vol 441 ◽  
Author(s):  
Wen-Jie Qi ◽  
Zhi-Sheng Wang ◽  
Zhi-Guang Gu ◽  
Guo-Ping Ru ◽  
Guo-Bao Jialig ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Electrical Measurements ◽  
Polycrystalline Structure ◽  
X Ray ◽  
Post Annealing ◽  
And Diffusion

AbstractThe ion-beam-sputtered polycrystalline SiGe film and its doping properties have been studied. Boron and phosphorus have been doped into the sputtered poly-SiGe film by ion implantation and diffusion. To activate the implanted impurities, both rapid thermal annealing and fiirnace annealing have been used. The electrical measurements show that boron and plhosphorus can be doped into sputtered SiGe films and effectively activated by both ion implantation with post-annealing and diffiision. Hall mobilities as high as 31 cm2/V-s and 20 cm2/V.s have been obtained in B-difflhsed and P-diffused SiGe films, respectively. The x-ray diffraction spectra of the sputtered Sifie filhn show its typical polycrystalline structure with (111), (220) and (311) as the preferential orientations.

Formation of Cosi2-Shallow Junctions By Ion Beam Mixing and Rapid Thermal Annealing

1990 ◽  
Vol 181 ◽  
Author(s):  
L. Niewöhner ◽  
D. Depta
Keyword(s):  
Ion Implantation ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
Dopant Distribution ◽  
Junction Depth ◽  
Ion Beam Mixing ◽  
Sem And Tem ◽  
Shallow Junctions

ABSTRACTFormation of CoSi2 using the technique of ion implantation through metal (ITM) and subsequent appropriate rapid thermal annealing is described. Silicide morphology is investigated by SEM and TEM. SIMS and RBS are used to determine dopant distribution and junction depth. Self-aligned CoSi2/n+p diodes produced in this technique are presented.

Formation of Gallium Nitride (GaN) Transition Layer by Plasma Immersion Ion Implantation and Rapid Thermal Annealing

2000 ◽  
Vol 618 ◽  
Author(s):  
D. T. K. Kwok ◽  
A. H. P. Ho ◽  
X. C. Zeng ◽  
C. Chan ◽  
P. K. Chu ◽  
...  
Keyword(s):  
Gallium Nitride ◽  
Ion Implantation ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
Chemical Vapor ◽  
Crystal Form ◽  
Organic Chemical ◽  
Plasma Immersion Ion Implantation ◽  
Amorphous Surface

ABSTRACTRecent advances in the preparation of gallium nitride (GaN) and related compounds have made possible the production of blue semiconductor laser. Conventional preparation involves growing GaN thin films on lattice-mismatching sapphire using metal-organic chemical vapor deposition (MOCVD). In this article, we describe an alternative method to produce a lattice-matching strained layer in GaAs for subsequent GaN growth by plasma immersion ion implantation (PIII) followed by rapid thermal annealing. Our novel approach uses broad ion impact energy distribution and multiple implant voltages to form a spread-out nitrogen depth profile and an amorphous surface layer. This approach circumvents the retained dose and low nitrogen content problems associated with ion beam implantation at fix energy. Based on our Raman study, the resulting structure after PIII and rapid thermal annealing is strained and contains some GaN possibly in crystal form

GaAs/AlGaAs Quantum Well Mixing Using Low Energy Ion Implantation and Rapid Thermal Annealing

1988 ◽  
Vol 144 ◽  
Author(s):  
B. Elman ◽  
Emil S. Koteles ◽  
P. Melman ◽  
C. A. Armiento
Keyword(s):  
Ion Implantation ◽  
Quantum Wells ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
Low Energy ◽  
Exciton Transition ◽  
Transition Energies ◽  
Diffusion Of Vacancies ◽  
Implantation Fluence

ABSTRACTLow energy ion implantation followed by rapid thermal annealing (RTA) was utilized to modify exciton transition energies of MBE- rown GaAs/AlGaAs quantum wells (QW). The samples were irradiated with an 75As ion beam with an energy low enough that the depth of the disordered region was spatially separated from the QWs. After RTA, exciton energies (determined using optical spectroscopy) showed large increases which were dependent on QW widths and the implantation fluence with no significant increases in peak linewidths. These energy shifts were interpreted as resulting from the modification of the shapes of the as-grown QWs from square (abrupt interfaces) to rounded due to enhanced Ga and Al interdiffusion in irradiated areas. These results are similar to our data on the RTA of the same structures capped with SiO2 and are consistent with the model of enhanced intermixing of Al and Ga atoms due to diffusion of vacancies generated near the surface.

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