New Approaches for Formation of Ultra-Thin PtSi Layers for Infrared Applications

1998 ◽  
Vol 514 ◽  
Author(s):  
Ricardo A. Donaton ◽  
Sing Jin ◽  
Hugo Bender ◽  
Maxim Zagrebnov ◽  
Kris Baert ◽  
...  
Keyword(s):  
Schottky Barrier ◽  
Infrared Detector ◽  
High Vacuum ◽  
Deposition Process ◽  
Critical Issue ◽  
Device Fabrication ◽  
Thin Layers ◽  
Process Window ◽  
Detector Performance ◽  
Silicide Layer

ABSTRACTPtSi is one of the most used silicides in infrared Schottky barrier detectors due to its low Schottky barrier to p-type Si ( Øb ∼ 0.23 eV). Control of the thickness and uniformity of the silicide layer is fundamental for a good infrared detector performance, since the silicide thickness has to be in the range of 3 to 8 nm. Such thin layers are usually made by evaporation of Pt followed by a furnace annealing. We will show different approaches for fabrication of utra-thin PtSi layers. In all of the processes, high-vacuum sputtering is used for Pt deposition and the silicidation is performed in a rapid thermal annealing system. Smooth and uniform Pt Si layers down to 3 nm thick are formed in this way. It will be shown that the controllability of the thickness during sputter deposition is not a critical issue and the deposition process has a large process window. Moreover, when taking an optimal approach, a large process window can also be found for the RTA step. The implementation of these approaches for device fabrication and some electrial results of diodes made with them will also be presented.

Effect Of Phosphorus On Ge/Si(001) Island Formation

2002 ◽  
Vol 737 ◽  
Author(s):  
Theodore I. Kamins ◽  
Gilberto Medeiros-Ribeiro ◽  
Douglas A. A. Ohlberg ◽  
R. Stanley Williams
Keyword(s):  
Deposition Rate ◽  
Strain Energy ◽  
Competitive Adsorption ◽  
Lattice Mismatch ◽  
Three Dimensional ◽  
Deposition Process ◽  
Thin Layers ◽  
Island Size ◽  
Partial Pressures ◽  
Intermediate Size

ABSTRACTWhen Ge is deposited epitaxially on Si, the strain energy from the lattice mismatch causes the Ge in layers thicker than about four monolayers to form distinctive, three-dimensional islands. The shape of the islands is determined by the energies of the surface facets, facet edges, and interfaces. When phosphorus is added during the deposition, the surface energies change, modifying the island shapes and sizes, as well as the deposition process. When phosphine is introduced to the germane/hydrogen ambient during Ge deposition, the deposition rate decreases because of competitive adsorption. The steady-state deposition rate is not reached for thin layers. The deposited, doped layers contain three different island shapes, as do undoped layers; however, the island size for each shape is smaller for the doped layers than for the corresponding undoped layers. The intermediate-size islands are the most significant; the intermediate-size doped islands are of the same family as the undoped, multifaceted “dome” structures, but are considerably smaller. The largest doped islands appear to be related to the defective “superdomes” discussed for undoped islands. The distribution between the different island shapes depends on the phosphine partial pressure. At higher partial pressures, the smaller structures are absent. Phosphorus appears to act as a mild surfactant, suppressing small islands.

Chemical Vapor Deposition of Sr1−xBaxNb2O6 Thin Films Using Metal Alkoxide Precursors

2000 ◽  
Vol 15 (8) ◽  
pp. 1702-1708
Author(s):  
Ruichao Zhang ◽  
Ren Xu
Keyword(s):  
Thin Films ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Single Phase ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Thin Layers ◽  
Metal Alkoxide ◽  
Stoichiometry Control ◽  
Alkoxide Precursors

A novel two-step metalorganic chemical vapor deposition process was used in this study to prepare Sr1−xBaxNb2O6 (SBN) thin films. Two thin layers of single-phase SrNb2O6 and BaNb2O6 were deposited alternately on a silicon substrate, and the solid solution of SBN was obtained by high-temperature annealing. The stoichiometry control of the SrNb2O6 and the BaNb2O6 thin films was achieved through deposition process control, according to the evaporation characteristics of double metal alkoxide. The evaporation behavior of double metal alkoxide precursors SrNb2(1-OC4H9)12 and BaNb2(1-OC4H9)12 was studied, and the results were compared with the evaporation of single alkoxide Nb(1-OC4H9)5.

scholarly journals Electrical Characterization of Postmetal Annealed Ultrathin TiN Gate Electrodes in Si MOS Capacitors

2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Z. N. Khan ◽  
S. Ahmed ◽  
M. Ali
Keyword(s):  
Electrical Characterization ◽  
Atomic Layer ◽  
Device Fabrication ◽  
Process Window ◽  
Gate Stacks ◽  
Mos Capacitors ◽  
Hafnium Silicate ◽  
Gate Electrodes ◽  
Layer Deposition ◽  
Tin Metal

Focusing on sub-10 nm Silicon CMOS device fabrication technology, we have incorporated ultrathin TiN metal gate electrode in Hafnium Silicate (HfSiO) based metal-oxide capacitors (MOSCAP) with carefully chosen Atomic Layer Deposition (ALD) process parameters. Gate element of the device has undergone a detailed postmetal annealed sequence ranging from 100°C to 1000°C. The applicability of ultrathin TiN on gate electrodes is established through current density versus voltage (J-V), resistance versus temperature (R-T), and permittivity versus temperature analysis. A higher process window starting from 600°C was intentionally chosen to understand the energy efficient behavior expected from ultrathin gate metallization and its unique physical state with shrinking thickness. The device characteristics in form of effective electronic mobility as a function of inverse charge density were also found better than those conventional gate stacks used for EOT scaling.

Theoretical modelling of MWIR thermoelectrically cooled nBn HgCdTe detector

2013 ◽  
Vol 61 (1) ◽  
pp. 211-220 ◽  
Author(s):  
P. Martyniuk ◽  
A. Rogalski
Keyword(s):  
Bias Voltage ◽  
State Of The Art ◽  
Structural Parameters ◽  
Infrared Detector ◽  
Differential Resistance ◽  
The State ◽  
Theoretical Modelling ◽  
Detector Performance ◽  
Type Detector ◽  
Hgcdte Detector

Abstract The paper reports on the medium wavelength infrared (MWIR) unipolar barrier infrared detector (UBIRD) nBn/B-n type (n-type barrier) HgCdTe detector’s photoelectrical performance. The UBIRD nBn/B-n type HgCdTe detector was modelled using commercially available software APSYS. Detailed analysis of the detector’s performance (such as dark current, photocurrent, responsivity, and detectivity) versus bias voltage, operating temperatures, and structural parameters (cap, barrier, and absorber’s doping as well as cap and barrier compositions) were performed pointing out optimal working conditions. Both conduction and valence band alignments of the HgCdTe nBn/B-n type detector structure was simulated stressing their importance on detectors performance. It was shown that higher operation temperature (HOT) conditions achieved by commonly used thermoelectric (TE) coolers allow to obtain detectivities of D* = (3-10)×109 cmHz1/2/W at T = 200 K for detectors with cut-off wavelength of 5.2 μm The differential resistance area product of RA = 0.15-0.4 cm2 at T = 230 K for bias voltage V = 50 mV was estimated. Finally, the state of the art of UBIRD HgCdTe nBn/B-n type detector performance was compared to InAs/GaSb/B-Al0.2Ga0.8Sb T2SLs nBn detector, InAs/GaSb T2SLs PIN and the HOT HgCdTe bulk photodiodes’ operated at near-room temperature (T = 230 K). It was shown that the RA product of the MWIR UBIRD nBn/B-n type HgCdTe detector can reach a comparable level to the state of the art of the HgCdTe HOT bulk photodiodes and two types of type-II superlattice detectors: PIN photodiodes and nBn detectors

Stress in Titanium Disilicide Layers, During and After Formation.

1988 ◽  
Vol 130 ◽  
Author(s):  
J. F. Jongste ◽  
F. E. Prins ◽  
G. C. A. M. Janssen ◽  
S. Radelaar
Keyword(s):  
Silicon Substrate ◽  
Semiconductor Device ◽  
Linear Thermal Expansion ◽  
Deposition Process ◽  
Device Fabrication ◽  
Titanium Disilicide ◽  
Titanium Layer ◽  
Thermal Expansion Coefficients ◽  
The Difference ◽  
Interconnect Lines

AbstractDuring and after formation of a thin layer of titanium disilicide (TiSi2) on a silicon substrate stress is caused in several ways: Intrinsic stresses are due to the deposition process or to phase transformations and grain growth of the deposited material. Extrinsic stresses are caused by thermal effects: the difference in linear thermal expansion coefficients of the layer and the substrate respectively. Problems related to stresses can occur in semiconductor device fabrication. Stresses can deteriorate gate oxides in MOSFETs and can cause cracks in interconnect lines. Also, focusing problems in lithographic steps can occur because of wafer warpage. In this paper some examples of the different types of stress that can occur are shown and discussed. Both multilayer and self aligned Ti-Si samples have been studied: The advantage of the use of Ti-Si multilayers to produce TiSi2 is that diffusion has to proceed only over a short distance i.e., the multilayer period. So the annealing time can be short. In the self aligned silicidation process, where a layer of a titanium layer on top of a silicon substrate is annealed, the diffusion length is equal to the thickness of the Ti layer. Because longer annealing times are needed, the latter type is used to monitor stress during formation.

A Mechanism of Sliding on the Nanometer-Thick Ag Layers

2005 ◽  
Author(s):  
F. Honda ◽  
M. Goto
Keyword(s):  
Friction Coefficient ◽  
Normal Load ◽  
High Vacuum ◽  
High Energy ◽  
Thin Layers ◽  
Ultra High Vacuum ◽  
Wear And Friction ◽  
Thickness Measurements

Tribological performance of sub-nano to nanometer-thick Ag layers deposited on Si(111) have been examined to understand the role of surface thin layers to the wear and friction characteristics. The slider was made of diamond sphere of 3 mm in radius. Sliding tests were carried out in an ultra-high vacuum environment (lower than 4 × 10−8 Pa) and analyzed in-situ by Auger electron spectroscopy (AES) for the quantitative thickness-measurements, by reflection high-energy electron diffraction (RHEED) to clarify the substrate cleanliness and crystallography of the Ag films, and by scanning probe microscopy (SPM) for the morphology of the deposited/slid film surfaces. As the results, a minimum of the friction coefficient 0.007 was observed from the film thickness range of 1.5–10 nm, and exactly no worn particles were found after 100 cycles of reciprocal sliding. Results have directly indicated that solid Ag(111) sliding planes allowed to reduce the friction coefficient very low without any detectable wear particles, and Ag nanocrystallites in Ag polycrystalline layers increase the size to 20–40 nm order, during sliding. The friction coefficient was slightly dependent to the normal load. Results were discussed on the role of the surface atoms to the friction, and a mechanism of sliding on Ag thin layers.

Analysis Of Sige Fet Device Structures On Silicon-on-sapphire Substrates by X-Ray Diffraction

1998 ◽  
Vol 533 ◽  
Author(s):  
P. M. Mooney ◽  
J. O. Chu ◽  
J. A. Ott ◽  
J. L. Jordan-Sweet ◽  
B. S. Meyerson ◽  
...  
Keyword(s):  
Field Effect Transistors ◽  
High Vacuum ◽  
Chemical Vapor ◽  
Device Fabrication ◽  
Ultra High Vacuum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sapphire Substrates ◽  
Wafer Cleaning ◽  
Device Structures

AbstractSi/Si1-xGex, heterostructures on improved silicon-on-sapphire substrates were grown epitaxially by ultra-high vacuum chemical vapor deposition for application as p-channel field effect transistors. High-resolution triple-axis x-ray diffraction was used to analyze these structures quantitatively and to evaluate the effects of device fabrication processes on them. Out-;diffusion of Ge from the Si1-xGex, quantum well was observed after fabrication as was the change in thickness of the Si cap layer due to wafer cleaning and gate oxidation at 875 °C

Study of Photovoltaic Devices with Hybrid Active Layer

2019 ◽  
Vol 293 ◽  
pp. 51-64
Author(s):  
Pawel Jarka ◽  
Tomasz Tański ◽  
Bartlomiej Hrapkowicz ◽  
Barbara Hajduk ◽  
Kamil Bystroń ◽  
...  
Keyword(s):  
Optical Properties ◽  
Bulk Heterojunction ◽  
Photovoltaic Cells ◽  
Deposition Process ◽  
Thin Layers ◽  
Force Microscopy ◽  
Active Layers ◽  
Transmission Electron ◽  
Current Voltage ◽  
The Individual

The aim of this work is to present the influences of composition of the material and manufacturing technology conditions of the organic photovoltaics devices (OPv) with the organic and hybrid bulk heterojunction on the active layers properties and cells performance. The layers were produced by using small molecular compounds: the metal-phthalocyanine (MePc) and perylene derivatives (PTCDA) and the titanium dioxide (TiO2) nanoparticles. Two kinds of metal phthalocyanines (NiPc, TiOPc) were used as donor material and pperylenetetracarboxylic dianhydride (PTCDA) as an acceptor. The used manufacturing technique allowed to employ thin layers of materials in a fast deposition process. Bulk heterojunction was created by simultaneously applying the MePc:PTCDA materials during the evaporation of the components mixture.The research was based on the estimate of composition of bulk heterojunction, the examination of the surface morphology of the used layers and optical properties studies of the heterojunction and its implementation to photovoltaic architecture. The produced photovoltaic cells parameters were determined on the basis of current - voltage characteristics.The researches of structure of obtained layers were conducted by using scanning electron microscope (SEM) and transmission electron microscopy (TEM). The quantitative determination of surface topography by determining RMS and Ra coefficients were performed by atomic force microscopy (AFM). In order to determine the optical properties of the films the UV-Visible spectroscope have been utilized. Current - voltage characteristics were employed to determine the basic photovoltaic parameters using a dedicated device.The paper describes the influence of the individual components sharing the bulk heterojunction on its structure, optical properties and morphology of surface. In addition it allows for linking active layers properties with the parameters of the photovoltaic cells. The obtained results suggest the possibility of developing the utilized materials and technology in the further works on photovoltaic structures.

Microfluidic liquid jet system with compatibility for atmospheric and high-vacuum conditions

Lab on a Chip ◽  
2014 ◽  
Vol 14 (10) ◽  
pp. 1733-1745 ◽  
Author(s):  
Martin Trebbin ◽  
Kilian Krüger ◽  
Daniel DePonte ◽  
Stephan V. Roth ◽  
Henry N. Chapman ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
High Vacuum ◽  
Device Fabrication ◽  
Liquid Jets ◽  
Liquid Jet ◽  
Flow Rates

A novel microfluidic device for the generation of liquid jets with micrometer diameters is described. The gas sheath design allows reliable jetting at sample-efficient flow rates under atmospheric and vacuum conditions. The soft-lithographic device fabrication is easy, reproducible and allows the integration of additional features such as a jet-in-jet.

Sign in / Sign up

Export Citation Format

Share Document