bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Temperature Ramping on MOCVD Al Film Properties
Authors: Yang D. , Jonnalagadda R. , Mahadev V. , Cale T. S. , Hillman J. T. , Foster R. F. 
Published: April 2011

ABSTRACTWe present and discuss experiments designed to demonstrate the effects of ramping substrate temperature during the deposition of TIBA sourced aluminum on Si(100) and TiNx coated silicon (TiN) wafers. We also present results from experiments in which the precursor flow was pulsed (started and stopped) for a short time at a higher temperature followed by temperature ramp down and deposition at a lower (constant) temperature on TiN wafers. Aluminum growth rates and crystal orientation data are presented for different deposition conditions on Si(100) wafers. Aluminum nucleation densities, crystal orientation, average grain size, surface roughness, growth rate and resistivity data are presented for different deposition conditions on TiN wafers. During substrate temperature ramp down from 673 K on TiN wafers, when the precursor flow was pulsed for a short time at higher temperatures, and then resumed at a lower (constant) temperature 573 K, there was a significant increase in both deposition rates and fraction of (111) orientation. The resistivities of these films were close to that of bulk aluminum. Films deposited during substrate temperature ramp down on TiN substrates resulted in higher fractions of (111) oriention and higher resistivities as compared to the films deposited at constant substrate temperature and during the ramp up of substrate temperature. The films deposited on Si(100) wafers during substrate temperature ramp down from 673 K to 573 K had strong Al(200) orientation.
Improvement of the Long-Term Stability of Polysilicon IC-Resistors by Fluorine Doping
Authors: Rydberg Matts , Smith Ulf 
Published: April 2011

ABSTRACTIn addition to exacting requirements regarding uniformity, precision and matching, thin-film polysilicon resistors for analog telecommunication circuits must be extremely stable. In this paper a new method for improving the stability of polysilicon resistors is presented. It utilizes the strength of the Si-F bond to prevent hydrogen and other impurity atoms from attaching to the dangling bonds in the grain boundaries and is based on individual control of implantation dose and annealing conditions for dopant and fluorine, respectively.Polysilicon films, 500 nm thick, were implanted with boron at a dose of 51014 cm-2 and annealed at 1000 °C. This was followed by an implantation of fluorine and another anneal. The fluorine dose ranged up to 1·1016 cm-2 and the annealing temperature was varied between 600 °C and 1000 °C.Resistivity measurements showed that the fluorine annealing temperature has to be higher than 700 °C to reduce implantation damage. The sensitivity of the polysilicon films to hydrogen, an important indication of their electrical stability, was investigated by annealing both in a hydrogen plasma and in a molecular hydrogen ambient. For low hydrogen sensitivity, the fluorine annealing temperature has to be less than 750 °C. The temperature was therefore set to 750 °C so as to strike a balance between a low hydrogen sensitivity and the need for a reduced implantation damage. SIMS measurements showed the amount of fluorine in the film to decrease by two orders of magnitude if the fluorine annealing temperature was 1000 °C, and to remain essentially constant if the temperature was 750 °C. Stress tests were made in order to see the effect of fluorine on the resistivity during actual operating conditions. The stability of the resistors during the stress tests was found to improve by at least a factor of two when fluorine doping was used.
Low Temperature Deposited Highly-Conductive N-type SiC Thin Films
Authors: Cheng Kuan-Lun , Cheng Huang-Chung , Lee Wen-Horng , Lee Chiapyng , Yew Tri-Rung 
Published: April 2011

ABSTRACTLow-temperature deposited highly-conductive SiC films has long been a goal for many researchers involved in hetero-junction bipolar transistor, thin-film transistor, solar cell.… etc. Here in this paper, we study the influences of the diluted PH3 flow rates on SiC film quality as well as electrical properties. PH+ was determined from residual gas analyzer to be the main dopant source. Phosphorous atoms will play a role of enhancing the SiC grain growth and resulting in a smaller film growth rate. Carrier concentrations increase monotonically with the diluted PH3 flow rates. While Hall mobility first increases than decreases with it due to a combination effect of the impurity scattering and a film quality improvement which dominates when the 1% PH3/H2 flow rate is above or below 40 seem, respectively.
Highly Supersaturated, Highly Strained Sputtered Ag-Co and Ag-Ni Layers
Authors: Velterop L. , Buis A. , Delhez R. , de Keijser Th.H. , Mittemeijer E.J. , Reefman D. 
Published: April 2011

ABSTRACTThin Ag-Ni and Ag-Co layers with compositions of 0, 15, 22 to 28 at% Ni or Co were made by magnetron sputtering. TEM experiments revealed that the layers exhibited a {111} fiber texture with a high density of twins, always with the twinning plane parallel to the layer surface. X-ray diffraction and TEM results indicate that all Ni or Co is dissolved in the Ag, although some compositional inhomogeneity occurs: the layers are highly supersaturated with Ni or Co. Unlike the pure Ag layer, the Ag-Ni and Ag-Co layers exhibited high strains in the as prepared state.Upon annealing Ni or Co precipitated. The Ni precipitates were small, spherical particles oriented parallel to the surrounding Ag. The strains in the Ag-Ni and Ag-Co layers after annealing were less than the calculated thermal strains, but they were larger than the strain in the pure Ag layer after an equal annealing treatment.
AFM Observations of Oxide Morphologies Formed at high Temperatures
Authors: Czerwinski F. , Szpunar J.A. 
Published: April 2011

ABSTRACTThe growth surfaces of oxides formed at high temperatures on metallic substrates with different oxidation resistance were imaged using an atomic force microscope (AFM) in both contact and tapping modes. In addition to differences in morphology of NiO and TiO2 films, and their anisotropy of growth caused by the crystallographic orientation of substrate grains and by the type of substrate grain boundaries, some subtle growth features were documented. These include the nano-size steps of growth on the sidewalls of pyramidal grains of TiO2 and the nucleation at the intersection of NiO grain boundaries with NiO/gas interface. An example of a quantitative description of oxide/gas interface using roughness parameters is presented. This description is used to demonstrate the differences in evolution of oxide growth morphology for NiO doped with Ce growing by inward diffusion of oxygen anions or by outward diffusion of metal cations.
Surface Characteristics, Etching Behaviors and
Chemicalmechanical Polishing of Aluminum Alloy thin Films
Authors: Tseng Wei-Tsu , Wu Jun , Chang Yee-Shyi 
Published: April 2011

ABSTRACTEtching behaviors of various Al alloy thin films in
H2O2-based acidic etchants are investigated in this
study. The pH and H2O2 content in the etchant are
varied in order to simulate the case where Al thin films are subject to
chemical-mechanical polishing (CMP) using slurries of different
compositions. Corrosion current and thickness of the native oxide on
pure-Al, AI-1%Si, Al-0.5%Cu, AI-1%Si-0.5%Cu, and AI-1%Cu thin films are
determined from Tafel and ESCA analyses respectively. Comparisons between
etch rate and CMP polish rate data suggest that Al-CMP removal process
depends strongly on the chemical reactions by the oxidizer (slurry).
Mechanical abrasion by the abrasive particles plays only an auxiliary role
during Al CMP. In addition, alloy composition (% Si and % Cu) influence both
etching and polishing behaviors to a great extent. The underlying mechanisms
for etching and polishing are discussed.
Chemical Mechanical Cleaning for Post-CMP Applications: Defects
and Metals Results
Authors: Zhao E. Y. , Emami R. , Malik I. , Mishra K. , Krusell W. C. , de Larios J. , Hymes D. J. 
Published: April 2011

ABSTRACTDouble-sided brush scrubbing has become a dominant method for post-CMP
cleaning applications. Chemicals delivered in-situ with brush scrubbing
greatly enhance the cleaning capabilities. In this paper, the effect of
dilute HF on reducing particulate defects and trace metal contamination on
polished oxide surface is studied using a HF-compatible double-sided
scrubber. AFM data on the interaction of dilute HF with oxide / tungsten
plug array after tungsten CMP is also presented. Scrubbing with dilute HF is
shown to be highly effective is removing slurry agglomerates that strongly
adhere to the post-CMP oxide film.
Particulate Removal from Silicon Substrates in
Megasonic-Assisted Dilute SC1 Chemistry
Authors: Kashkoush Ismail , Brause Eric , Grant Robert , Novak Rich 
Published: April 2011

ABSTRACTThis paper demonstrates the use of megasonic energy to enhance particulate
removal in dilute SC1 solutions. Ideal, as well as “real world”, particles
were deposited on silicon wafers to challenge the SCl/megasonic particle
removal system. Different dilute SCI concentrations were used, e.g., 1:4:20,
1:10:120, and 1:1:100. Bath temperature was varied between 50 and 70°C with
megasonic energy kept constant at 800 W. Results showed that the megasonic
energy enhanced the particle removal even in dilute solutions. The chemical
concentrations were shown to be a significant factor and must be monitored
or controlled in dilute SC1 solutions for particle removal to take place. A
lower cost of ownership can be obtained from these techniques as a result of
using dilute chemicals and extending current bath lives.
Effect of Ultra-Dilute RCA Cleans on the Integrity of Thin Gate
Oxides
Authors: Dhayagude Tushar , Chen Weidong , Shenasa Mohsen , Nelms David , Olesen Mike 
Published: April 2011

ABSTRACTComparative studies on the effect of Ultra-dilute RCA cleans,
chemical ratios in excess of 300:1, and Dilute RCA cleans,
chemical ratios around 50:1, on the integrity of thin gate oxides have been
performed. Ultra-dilute RCA chemistries have shown particle removal
efficiency, metallic contamination removal, surface roughness, Qbd, BVox and
defect density equivalent to those obtained using dilute RCA chemistries.
Furthermore ultra-dilute chemistries use less chemical leading to shorter
rinse times and thus increased throughput as compared to the dilute RCA
chemistries.
Study on Cu Cleaning Efficacy Depending on Initial Contamination
Method
Authors: Kim J. S. , Morita H. , Joo J. D. , Ohmi T. 
Published: April 2011

ABSTRACTWe investigated a dependence of cleaning efficiency for Cu on the initial
contamination method with different initial concentration and contamination
solution. Through this study, we found that the cleaning efficiency of
typical dissoluble chemical solutions such as O3-UPW, SPM and HPM
for Cu contaminated in diluted-hydrofluoric acid (DHF) was better than for
that in ultrapure water (UPW). And, it is shown that there is a dependence
of cleaning efficiency for Cu contaminated in UPW. The different desorption
behaviors of Cu contaminated in UPW and DHF can be interpreted by the fact
that the Cu is included in metal-induced-oxide (MIO) grown during
contamination in UPW and can not be removed by only dissolution process of
O3-UPW, SPM and HPM solutions which have no etching effect on
SiO2 and Si. In contrast, a relatively low concentration Cu
contaminated in DHF which has no MIO effect can be removed below the
detection limit by only dissolution process of these chemical solutions.
However, Cu contaminated in DHF is dissolved and inserted in the chemical
oxide grown during cleaning process as the initial Cu concentration is a
relatively high. Consequently, we conclude that Cu on Si surface can be
fundamentally removed by just dissolution process of typical dissoluble
chemicals except the amount of Cu inserted in MIO grown during contamination
in UPW and chemical oxide grown in chemical solutions.
In-Situ Chemical Concentration control cor Wafer Wet
Cleaning
Authors: Kashkoush Ismail , Brause Eric , Novak Richard , Grant Robert 
Published: April 2011

ABSTRACTThe continuously increasing integration of today's advanced semiconductors
requires increasingly tight process control in the IC manufacturing steps.
This paper demonstrates the use of conductivity sensors to monitor and
control the chemical concentrations of RCA cleaning and HF etching
solutions. Electrodeless conductivity sensors were used to monitor and
regulate the concentration of these process chemicals. A linear relationship
between the conductivity of the solution and the chemical concentration was
obtained within the range studied. A chemical monitoring and concentration
scheme (ICE-1™) was developed. Different concentrations of RCA and HF
solutions were investigated. Results show that these techniques are suitable
for monitoring and controlling the concentration of chemicals in the process
tanks for better process control. These techniques provide a lower cost of
ownership of the process due to longer bath lives and the use of dilute
chemicals.
Advanced Alkali Cleaning Solution for Simplification of
Semiconductor Cleaning Process
Authors: Morinaga Hitoshi , Aoki Masumi , Maeda Toshiaki , Fujisue Masaya 
Published: April 2011

ABSTRACTNH4OH/H2O2/H2O (called APM or
SC–1) cleaning combined with megasonic irradiation is found to feature
outstanding removal efficiency for various types of particulate contaminant.
The conventional APM cleaning, however, allows metallic impurity in solution
to adhere onto substrate surface, and it must be followed by acid cleaning
such as HCI/IH2O2/H2O (called HPM or SC–2)
cleaning to remove metallic impurity from substrate. The advanced APM
cleaning using MC–1 which is alkali cleaning agent containing chelating
agent has been developed, and this new cleaning is found capable for
preventing various metallic impurities including Al in solution from
contaminating substrate surface. Besides, with cleaning conditions
optimized, the advanced APM cleaning using MC–1 can also remove metallic
impurity from substrate surface. In short, this modified APM cleaning is
capable for removing particle and metallic impurity at the same time, which
is not possible with the conventional cleaning technology. The cleaning
process of semiconductor manufacturing process can be simplified if HPM
cleaning is eliminated by introducing the advanced APM cleaning using MC–1.
This leads to drastic reduction of cleaning cost and improvement of
throughput of the cleaning process.
Influence of Surface Organic Contamination on the Incubation
Time in Low-Pressure Chemical Vapor Deposition of Silicon Nitride on Silicon
Substrates
Authors: Saga Koichiro , Hattori Takeshi 
Published: April 2011

ABSTRACTTrace organic contaminants adsorbing on silicon surfaces during
transportation of wafers to a reaction chamber in an air ambient cause
incubation before film growth starts in low-pressure chemical vapor
deposition (LPCVD) of silicon nitride film on silicon substrates. The
incubation time for wafers either exposed to cleanroom air for a long period
without being stored in a box or stored in an outgassing plastic box prior
to LPCVD is longer than that for wafers transported to the CVD reactor
immediately after the previous step. It has been found that the longer
incubation time is attributed to not only extraneous oxide grown on the
silicon surface but also organic contaminants adsorbed on the surface.
Optimization of Post Sulfuric Acid/Hydrogen Peroxide Dump
Rinsing Processes
Authors: Chiarello R. P. , Parker R. , Helms C. R. , Chen W. , Tang S. , Cook L. J. 
Published: April 2011

ABSTRACTWe evaluated the rate limiting steps in a post sulfuric acid/hydrogen
peroxide mix dump rinsing process. The parameters we examined include, the
pull-out velocity from the chemical bath, the draining during transport into
the rinse tank, immersion into the rinse tank, dumping, draining after a
dump cycle and flow rate during fills between dumps. Based on our
investigations an optimized dump rinsing process was developed using
programmed flow rates and dumping cycles. The quality of the optimized
rinsing process was determined by measuring sulfur residue and light point
defects on wafer surfaces that had undergone the optimized rinsing process.
This optimized process requires 5 minutes and 75 liters of water, replacing
a process that initially ran for up to 16 minutes and consumed 600 liters of
water. Our optimized rinsing process, resulted in a factor of five saving in
water consumption and two in cycle lifetime with no statistical degradation
in surface quality.
In-homogeneous precipitation of Iron from SC1
Solutions
Authors: Knotter D. Martin , de Gendt Stefan , Mertens Paul , Heyns Marc M. 
Published: April 2011

ABSTRACTIt is found that Fe in a ppb level Fe-spiked SC1 solution precipitates
in-homogenous. The local high iron concentrations are difficult to rinse,
create micro-roughness, and induce weak spots in capacitors. With AFM it has
been shown that rings of 3–8 μm are etched in the silicon and that the etch
products (silicates) are deposited on one side just outside the ring. The
capacitor yield loss induced by this SC1 treatment can not be recovered
fully by a subsequent SC2 or dHCL step, while a dHF/dHCl does fully recover
the yield and removes the iron and silicate rim.
Measurement and Characterization Techniques for Thermoelectric Materials
Authors: Tritt Terry M. 
Published: April 2011

AbstractCharacterization of thermoelectric materials can pose many problems. A temperature difference can be established across these materials as an electrical current is passed due to the Peltier effect. The thermopower of these materials is quite large and thus large thermal voltages can contribute to many of the measurements necessary to investigate these materials. This paper will discuss the characterization techniques necessary to investigate these materials and provide an overview of some of the potential systematic errors which can arise. It will also discuss some of the corrections one needs to consider. This should provide an introduction to the characterization and measurement of thermoelectric materials and provide references for a more in depth discussion of the concepts. It should also serve as an indication of the care that must be taken while working with thermoelectric materials.
Thermopower, Electrical and Hall Conductivity of Undoped and Doped Iron Disilicide Single Crystals
Authors: Heinrich A. , Behr G. , Griessmann H. , Teichert S. , Lange H. 
Published: April 2011

AbstractThe electrical transport properties of β-FeSi2 single crystals have been investigated in dependence on the purity of the source material and on doping with 3d transition metals. The transport properties included are electrical conducticvity, Hall conductivity and thermopower mainly in the temperature range from 4K to 300K. The single crystals have been prepared by chemical transport reaction in a closed system with iodine as transport agent. In undoped single crystals prepared with 5N Fe both electrical conductivity and thermopower depend on the composition within the homogeinity range of β-FeSi2 which is explained by different intrinsic defects at the Sirich and Fe-rich phase boundaries. In both undoped and doped single crystals impurity band conduction is observed at low temperatures but above 100K extrinsic behaviour determined by shallow impurity states. The thermopower shows between 100K and 200K a significant phonon drag contribution which depends on intrinsic defects and additional doping. The Hall resistivity is considered mainly with respect to an anomalous contribution found in p-type and n-type single crystals and thin films. In addition doped single crystals show at temperatures below about 130K an hysteresis of the Hall voltage. These results make former mobility data uncertain. Comparison will be made between the transport properties of single crystals and polycrystalline material.
Overview of Industry Interest in New Thermoelectric Materials
Authors: Lyon H.B. 
Published: April 2011

AbstractThe technology base for air conditioning, refrigeration, component cooling below ambient temperatures and power generation will be required to meet several new challenges. The main lines of these challenges will be presented in a way which relates them to the several new thermoelectric materials and materials engineering options being pursued by the research community. The potential benefits of thermoelectric devices are only partially met by enhancing the figure of merit ZT, the nature of the design challenge and the resulting systems approach are presented. The research and the industry are entering into a new era.
Mapping Detector Response Over the Area of a CdZnTe-Multiple-Electrode Detector
Authors: Lingren C. L. , Apotovsky B. , Butler J. F. , Doty F. P. , Friesenhahn S. J. , Oganesyan A. , Pi B. , Zhao S. 
Published: April 2011

AbstractSemiconductor multiple-electrode detectors have been developed for the purpose of reducing effects of hole trapping in room-temperature radiation detectors.1,2 Some reported geometries maintain a nearly-uniform electric field inside the detector, but others generate an electric field that is very non-uniform and highly-concentrated at the anode. This paper reports the results of mapping such a detector (having a non-uniform electric field) with a finely collimated gamma-ray beam to determine the detector response as a function of position.
PbTe(Ga) – New Multispectralir Photodetector
Authors: Belogorokhov A. I. , Ivanchik I. I. , Khokhlov D. R. 
Published: April 2011

AbstractDoping of the lead telluride - narrow-gap semiconductor - with gallium results under certain conditions in the Fermi level pinning in the gap thus providing the semiinsulating state of material. Besides that, the persistent photoconductivity effect is observed at a temperatures T < T, = 80 K. The photoresponse kinetics consists of two parts: the slow one with the characteristic time tchar, going up to 104 s at T = 4.2 K, and the fast part with tchar of the order of 10 ms. We have measured the spectra of a fast part of the photoresponse using the Fouriertransform spectrometer “Bruker” IFS- 113v. The photoconductivity is observed in two spectral regions: in the middle- and far - infrared. Response in the middle-infrared consists of the ordinary fundamental band and a strong superimposed resonance-like structure just at the bandgap energy. The position of this spectral line may be tuned in a wide range (3.5–5.5) Pim by variation of temperature and/or composition of a lead telluride-based alloy. This middle-infrared photoresponse becomes considerable already at T = 160 K. The photoresponse in the far-infrared may be depending on the excitation conditions an analogous resonance-like structure at a wavelength 70 μm, or a broad band with the cutoff wavelength at least higher than 500 μm, which is the highest cutoff wavelength for the photon detectors observed up to date.
Reactive Ion Etching (RIE) Induced p- to n-Type Conversion in Extrinsically Doped p-Type HgCdTe
Authors: Musca C. A. , Smith E. P. G. , Siliquini J. F. , Dell J. M. , Antoszewski J. , Piotrowski J. , Faraone L. 
Published: April 2011

AbstractMercury annealing of reactive ion etching (RIE) induced p- to n-type conversion in extrinsically doped p-type epitaxial layers of HgCdTe (x=0.3 1) has been used to reconvert n-type conversion sustained during RIE processing. For the RIE processing conditions used (400mT, CH4/H2, 90 W) p- to n-type conversion was observed using laser beam induced current (LBIC) measurements. After a sealed tube mercury anneal at 200°C for 17 hours, LBIC measurements clearly indicated no n-type converted region remained. Subsequent Hall measurements confirmed that the material consisted of a p-type layer, with electrical properties equivalent to that of the initial as-grown wafer (NA-ND=2×1016 cm−3,.=350 cm2.V−1. S−1).