Practical Aspects of Forming Ultra-Shallow Junctions by Sub-keV Boron Implants

1999 ◽  
Vol 568 ◽  
Author(s):  
M. A. Foad ◽  
A. J. Murrell ◽  
E. J. H. Collart ◽  
G. de Cock ◽  
D. Jennings ◽  
...  
Keyword(s):  
Process Integration ◽  
Practical Aspect ◽  
High Concentration ◽  
Process Data ◽  
Complex Process ◽  
Boron Implantation ◽  
Rapid Temperature ◽  
Ultra Shallow Junctions ◽  
Interface Structures ◽  
Ion Species

ABSTRACTAs the drive towards the production of 100 nm CMOS devices pick up speed, the practical aspect of transistor shallow junction formation, including a large menu of process integration issues, must now be solved in a short order. The most direct path to 50 nm junction depths is through the sub-keV boron implantation and rapid thermal annealing.The material aspects of the process integration centers on: (1) CMOS devices for shallow, highly-activated and abrupt junctions (involving the choice of ion species [B, BF, B10H14, BSi2, etc.], substrate materials [ Cz, Epi, SOI], anneal conditions [ramp rate, soak time, ambient gas], etc.) and (2) Defect-dopant interactions during annealing (including surface reactions of high concentration species [B, F], diffusion and carrier trapping by background and co-implanted species [C, 0, F, etc.].Process data for atomic and electrical activity profiles as well as defect and interface structures will be presented to illustrate progress towards understanding these complex process interactions. A particular focus will be the effects of anneal ambient and rapid temperature rise times approaching the “pike” anneal ideal.

Ultra-Shallow Junctions for the 65nm Node Based on Defect and Stress Engineering

2005 ◽  
Vol 864 ◽  
Author(s):  
Victor Moroz ◽  
Majeed Foad ◽  
Houda Graoui ◽  
Faran Nouri ◽  
Dipu Pramanik ◽  
...  
Keyword(s):  
Stress Gradient ◽  
Process Window ◽  
Boron Diffusion ◽  
High Concentration ◽  
Stress Effects ◽  
Ion Channeling ◽  
Rapid Temperature ◽  
Ultra Shallow Junctions ◽  
High Concentrations ◽  
Non Equilibrium

AbstractThe co-implantation of germanium, carbon, and boron with the optimum implant energies and doses makes it possible to create p+/n junctions with the sheet resistance of less than 600 Ohm/square and the slope of less than 3 nm/decade. The narrow process window is based on careful engineering of the amorphization, point defects, and stresses and includes standard 1050°C spike annealing. The germanium pre-amorphization suppresses the ion channeling for the subsequent boron implant. The tensile stress induced by the substitutional carbon atoms and the compressive stress induced by the substitutional germanium atoms slow down boron diffusion and help to make the junctions shallower. The stress gradient in the transition region from the strained carbon and germanium doped layers to the relaxed silicon underneath creates an uphill boron flux that makes the junction slope steeper.The optimum amount of carbon is placed in between the implanted boron and the implant damage, which is located below the amorphized layer. During the annealing, the carbon atoms capture silicon interstitials that are coming from the implant damage and form carbon-interstitial clusters. The analysis demonstrates that it is possible to capture over 95% of the interstitials this way before they have a chance to reach boron-doped layer. This completely suppresses the transient-enhanced boron diffusion (TED) and drastically reduces the amount of boron that is deactivated in boron-interstitial clusters (BICs). In fact, the point defect engineering with an optimized carbon profile allows to remove all non-equilibrium silicon interstitials that are generated by the following three sources: the implant damage below the amorphized layer, the rapid temperature ramp down, and the interstitials generated by boron at high concentrations (due to the effect known as boron-enhanced diffusion (BED)).The latter effect leads to significant increase of the apparent boron activation level beyond the well-characterized solid-state solubility level. We explain this effect as a reduction in formation of BICs due to the lack of interstitial supersaturation. In carbon-free silicon, high concentration boron is always accompanied by the non-equilibrium interstitials, coming from either the implant damage or the BICs even if boron is introduced into silicon by pre-deposition instead of the implantation. Extensive experiments and theoretical analysis based on simulation of the interaction of Ge, C, I, and B atoms, as well as the stress effects, point to the optimized process flow that improves the shape and parameters of the p+/n USJs.

Vacancy Engineering – An Ultra-Low Thermal Budget Method for High-Concentration 'Diffusionless' Implantation Doping

2008 ◽  
Vol 573-574 ◽  
pp. 295-304 ◽  
Author(s):  
Nicholas E.B. Cowern ◽  
Andrew J. Smith ◽  
Nicholas S. Bennett ◽  
Brian J. Sealy ◽  
Russell Gwilliam ◽  
...  
Keyword(s):  
Low Temperatures ◽  
High Performance ◽  
Silicon Films ◽  
Doping Profile ◽  
Junction Depth ◽  
High Concentration ◽  
Thermal Budget ◽  
Boron Implantation ◽  
Ultra Shallow Junctions ◽  
Low Thermal Budget

This paper reviews the physics and the potential application of ion-implanted vacancies for high-performance B-doped ultra-shallow junctions. By treatment of silicon films with vacancygenerating implants prior to boron implantation, electrically active boron concentrations approaching 1021 cm-3 can be achieved by Rapid Thermal Annealing at low temperatures, without the use of preamorphisation. Source/drain (S/D) junctions formed by advanced vacancy engineering implants (VEI) are activated far above solubility. Furthermore, in the case of appropriately engineered thin silicon films, this activation is stable with respect to deactivation and the doping profile is practically diffusionless. Sheet resistance Rs is predicted to stay almost constant with decreasing junction depth Xj, thus potentially outperforming other S/D engineering approaches at the ‘32 nm node’ and beyond.

What Does Self-Diffusion Tell Us about Ultra Shallow Junctions?

2000 ◽  
Vol 610 ◽  
Author(s):  
Ant Ural ◽  
Serene Koh ◽  
P. B. Griffin ◽  
J. D. Plummer
Keyword(s):  
Point Defects ◽  
High Concentration ◽  
Enhanced Diffusion ◽  
Self Diffusion ◽  
Native Point Defects ◽  
Junction Formation ◽  
Ultra Shallow Junctions ◽  
High Concentrations ◽  
Temperature Furnace ◽  
Dopant Profiles

AbstractUnderstanding the coupling between native point defects and dopants at high concentrations in silicon will be key to ultra shallow junction formation in silicon technology. Other effects, such as transient enhanced diffusion (TED) will become less important. In this paper, we first describe how thermodynamic properties of the two native point defects in silicon, namely vacancies and self-interstitials, have been obtained by studying self-diffusion in isotopically enriched structures. We then discuss what this tells us about dopant diffusion. In particular, we show that the diffusion of high concentration shallow dopant profiles is determined by the competition between the flux of mobile dopants and those of the native point defects. These fluxes are proportional to the interstitial or vacancy components of dopant and self-diffusion, respectively. This is why understanding the microscopic mechanisms of silicon self-diffusion is important in predicting and modeling the diffusion of ultra shallow dopant profiles. As an example, we show experimental data and simulation fits of how these coupling effects play a role in the annealing of shallow BF2 ion implantation profiles. We conclude that relatively low temperature furnace cycles following high temperature rapid thermal anneals (RTA) have a significant effect on the minimum junction depth that can be achieved.

scholarly journals THEORETICAL ASPECTS OF DIGITAL CREATION TOPOGRAPHIC PLAN

2021 ◽  
Vol 3 (163) ◽  
pp. 30-34
Author(s):  
O. Afanasyev ◽  
I. Zavada
Keyword(s):  
Coordinate System ◽  
Computer Software ◽  
Field Work ◽  
Process Data ◽  
Digital Maps ◽  
Complex Process ◽  
Software Product ◽  
Materials Used ◽  
Digital Plan ◽  
The City

Theoretical bases of creation of the digital topographic plan of district are considered, the analysis of the materials used for creation of the digital topographic plan of district is carried out. Types and features of application of topographic plans are analyzed. The most suitable geo-basis for creating a digital plan has been identified. Studies have shown that a 1: 500 scale geo-base is quite informative and most optimal for creating digital and conventional topographic plans in the city. Without additional removal, 1: 500 scale plans allow for the transition to smaller scale plans. According to current national regulations, a single coordinate and altitude system should be used to create topographic plans. Today, the only state coordinate system USK-2000 is used, which replaced the coordinate system SK-42, which is based on the Krasovsky ellipsoid and the Gauss-Krueger projection. Possibilities of development of electronic topographic plans with use of modern software complexes are investigated. Computer software allows you to process data as accurately as possible and perform tasks quickly. Among the main software packages used to create an electronic topographic plan of the area are AutoCAD, Digitals, Geonics, COMPASS, MapInfo Pro, Topocad. The choice of software product depends on the breadth of the task, the modernity of surveying instruments and their own software. An analysis of the software used in the creation of digital maps and topographic plans, which showed that the choice of a particular product depends on the breadth of the task, the modernity of surveying instruments and their own software. AutoCAD software is universal and fully adapted to modern geodetic problems. The use of AutoCAD software will ensure the final processing of data obtained during field work and the completion of the digital topographic plan of the area. The procedure for creating a digital topographic plan of the area using Digitals and AutoCAD software is considered. Creating a digital topographic plan of the area is a complex process consisting of several stages, which are described in the article.

Virtual Process Data Linkage of Assembly Stations in High Variance Workshop Production

2017 ◽  
Vol 871 ◽  
pp. 60-68
Author(s):  
Christian Sand ◽  
Dominik Manke ◽  
Jörg Franke
Keyword(s):  
Data Base ◽  
Value Chain ◽  
Data Linkage ◽  
Production Systems ◽  
Process Data ◽  
Local Data ◽  
Serial Production ◽  
Complex Process ◽  
Special Software ◽  
Virtual Process

The advance of digitalization changes the requirements of processes in industrial production and assembly. For this reason, production and assembly must now be able to execute complex process steps. This is about quality and productivity expectations, as well as flexibility and reliability of production, lines and plants [1]. Today, data is generated by almost every system, machine and sensor, yet it is hardly used for process optimization. Manufacturing processes are usually organized as workshop production or chained production systems, in addition to standalone machines [2,3]. Most analytic projects focus on chained systems and serial production, unlike individual machines and specific workshop production. Depending on manufacturing IT, process data from serial production is stored in data bases, which are usually optimized for traceability. Standalone machines and machines within workshop production are scarcely connected to a common data base. The required process data is stored either on the module itself or inside a local data base [4]. The identification of dependencies between individual assembly processes, energy data and the quality of the finished product is necessary for an extended optimization. These optimizations can be process-specific, as well as environmental and resource related. Due to decentralized process data storages, an overall view of a dynamic order-oriented value chain is denied. Therefore, the potential of the machines is largely unused. Based on Data Mining, this advanced development can be counteracted by process monitoring and optimization. Therefore, this paper provides a solution for a virtual process data linkage of assembly stations. This enables the acquisition, processing, transformation and storage of unstructured raw data by special software and methods, which is also able to cope with chained production systems and standalone machines. For further analysis of interdependencies, a visualization is developed for advanced monitoring and optimization [5,6].

scholarly journals Synthesis of Robust Water Reuse Networks Using Fuzzy Nonlinear Programming:Mass Exchange-Based Processes

2005 ◽  
Vol 5 (1) ◽  
pp. 22
Author(s):  
Raymond Girard R. Tan ◽  
Dennis E. Cruz
Keyword(s):  
Nonlinear Programming ◽  
Water Reuse ◽  
Process Integration ◽  
Limited Information ◽  
Process Data ◽  
Industrial Plants ◽  
Conflicting Objectives ◽  
Fuzzy Nonlinear Programming ◽  
Programming Process ◽  
Mass Loads

Water consumption and effluent generation in industrial plants can be effectively reduced by maximizing utilization of partially contaminated water. A dual approach consisting of graphical pinch methods for targeting followed by the synthesis of water reuse networks using such techniques as mathematical programming is usually employed. Reliable process data is necessary for successful plant retrofitting. In most cases, however, the necessary limiting concentrations and mass loads must be deduced from limited information. It thus becomes necessary to balance the conflicting objectives of minimizing water usage and of ensuring that sufficient stream concentrations fall within their limiting values. The use of fuzzy nonlinear programming for the synthesis of robust water reuse networks is demonstrated using a four-process case study from the literature. Keywords: Fuzzy nonlinear programming, process integration, and water reuse network (WRN).

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