Very brief Introduction to Ion Implantation for Semiconductor Manufacturing (2025)

IJERT-Modelling for Formation of Source/Drain Region by Ion Implantation and Diffusion Process for MOSFET Device

International Journal of Engineering Research and Technology (IJERT), 2013

https://www.ijert.org/modelling-for-formation-of-sourcedrain-region-by-ion-implantation-and-diffusion-process-for-mosfet-device https://www.ijert.org/research/modelling-for-formation-of-sourcedrain-region-by-ion-implantation-and-diffusion-process-for-mosfet-device-IJERTV2IS80676.pdf The main aim of this paper is to optimize the parameters needed to fabricate the MOSFET device using Active simulation process (simulator: MT3.00). The simulator consists of three programs hidden under one shell called MicroTech TM. It is well known that to fabricate MOSFET device, one of the most important steps is the formation of Source/Drain region. The ion implantation or diffusion process with different impurities is used for formation of source/drain region of MOSFET device. A comparative study is reported here between Arsenic and Boron concentration profile with ion implantation and diffusion process using the MicroTech simulator. To fabricate the n-channel MOSFET device, it is observed that in case of 70KeV ion energy doping concentration is maximum near to the surface, as observed from boron concentration profile using ion implantation process, which is also observed in case of p-channel MOSFET. To fabricate source/drain region of MOSFET device using diffusion process, it is observed that in case of 500⁰C doping concentration is maximum near to the surface for both kinds of dopants. Ion implantation process is more effective compared to the diffusion process as observed from the doping concentration profile in case of all dopants.

Atomic scale models of ion implantation and dopant diffusion in silicon

Thin Solid Films, 2000

We review our recent work on an atomistic approach to the development of predictive process simulation tools. First-principles methods, molecular dynamics simulations, and experimental results are used to construct a database of defect and dopant energetics in Si. This is used as input for kinetic Monte Carlo simulations. C and B trapping of the Si self-interstitial is shown to help explain the enormous disparity in its measured diffusivity. Excellent agreement is found between experiments and simulations of transient enhanced diffusion following 20±80 keV B implants into Si, and with those of 50 keV Si implants into complex B-doped structures. Our simulations predict novel behavior of the time evolution of the electrically active B fraction during annealing.

Ion Implantation for Semiconductor Doping and Materials Modification

Volume 4: Accelerator Applications in Industry and the Environment, 2012

In the 50-plus years since the patent was issued to William Shockley in 1957, ion implantation has become a key process in the commercial production of semiconductor devices, advanced engineering materials and photonic devices. This article reviews the fundamental concepts of production ion implanters for both the processes used in manufacturing and also in the design of the tools themselves. Recent publications in the application areas of semiconductors and materials modification are summarized, focusing on the attendant process effects. These results demonstrate that ion implantation is a well understood technology with abundant and evolving applications.

Atomistic calculations of ion implantation in Si: Point defect and transient enhanced diffusion phenomena

Applied Physics Letters, 1996

A new atomistic approach to Si device process simulation is presented. It is based on a Monte Carlo diffusion code coupled to a binary collision program. Besides diffusion, the simulation includes recombination of vacancies and interstitials, clustering and re-emission from the clusters, and trapping of interstitials. We discuss the simulation of a typical room-temperature implant at 40 keV, 5ϫ10 13 cm Ϫ2 Si into ͑001͒Si, followed by a high temperature ͑815°C͒ anneal. The damage evolves into an excess of interstitials in the form of extended defects and with a total number close to the implanted dose. This result explains the success of the ''ϩ1'' model, used to simulate transient diffusion of dopants after ion implantation. It is also in agreement with recent transmission electron microscopy observations of the number of interstitials stored in ͑311͒ defects.

Physical mechanisms of transient enhanced dopant diffusion in ion-implanted silicon

Journal of Applied Physics, 1997

Implanted B and P dopants in Si exhibit transient enhanced diffusion ͑TED͒ during annealing which arises from the excess interstitials generated by the implant. In order to study the mechanisms of TED, transmission electron microscopy measurements of implantation damage were combined with B diffusion experiments using doping marker structures grown by molecular-beam epitaxy ͑MBE͒. Damage from nonamorphizing Si implants at doses ranging from 5ϫ10 12 to 1ϫ10 14 /cm 2 evolves into a distribution of ͕311͖ interstitial agglomerates during the initial annealing stages at 670-815°C. The excess interstitial concentration contained in these defects roughly equals the implanted ion dose, an observation that is corroborated by atomistic Monte Carlo simulations of implantation and annealing processes. The injection of interstitials from the damage region involves the dissolution of ͕311͖ defects during Ostwald ripening with an activation energy of 3.8Ϯ0.2 eV. The excess interstitials drive substitutional B into electrically inactive, metastable clusters of presumably two or three B atoms at concentrations below the solid solubility, thus explaining the generally observed immobile B peak during TED of ion-implanted B. Injected interstitials undergo retarded diffusion in the MBE-grown Si with an effective migration energy of ϳ3.5 eV, which arises from trapping at substitutional C. The concept of trap-limited diffusion provides a stepping stone for understanding the enormous disparity among published values for the interstitial diffusivity in Si. The population of excess interstitials is strongly reduced by incorporating substitutional C in Si to levels of ϳ10 19 /cm 3 prior to ion implantation. This provides a promising method for suppressing TED, thus enabling shallow junction formation in future Si devices through dopant implantation. The present insights have been implemented into a process simulator, allowing for a significant improvement of the predictive modeling of TED.

Medium energy ion scattering analysis of the evolution and annealing of damage and associated dopant redistribution of ultra shallow implants in Si

Radiation Effects and Defects in Solids, 2009

As junction depths in advanced semiconductor devices move to below 20 nm, the process of disorder evolution during ion implantation at ultra low energies becomes increasingly influenced by the surface. This may also hold for shallow regrowth and dopant redistribution processes during subsequent thermal annealing of the substrate. The investigation of these near surface processes, requires analytical techniques with a depth resolution of ≤ 1 nm.

Ionization‐enhanced diffusion: Ion implantation in semiconductors

A model for the diffusion of implanted interstitials during implantation is introduced and shown to be able to account for the tails observed in ion profiles. It is argued that mechanisms of ionization-enhanced diffusion can explain some of the anomalous diffusion mechanisms observed in semiconductors. Indications for the existence of such mechanisms in the field of ion implantation in semiconductors are discussed.

Atomistic modeling of the effects of dose and implant temperature on dopant diffusion and amorphization in Si

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2001

We discuss atomistic simulations of ion implantation and annealing of Si over a wide range of ion dose and substrate temperatures. The DADOS Monte Carlo model has been extended to include the formation of amorphous regions, and this allows simulations of dopant diusion at high doses. As the dose of ions increases, the amorphous regions formed by cascades eventually overlap, and a continuous amorphous layer is formed. In that case, most of the excess interstitials generated by the implantation are swept to the surface as the amorphous layer regrows, and do not diuse in the crystalline region. This process reduces the amount of transient enhanced diusion (TED) during annealing. This model also reproduces the dynamic annealing during high temperature implants. In this case, the local amorphous regions regrow as the implant proceeds, without the formation of a continuous amorphous layer. For suciently high temperatures, each cascade is annealed out independently; interstitials and vacancies can escape from the cascade and thus increase dopant diusion. Ó

Atomistic modeling of dopant implantation, diffusion, and activation

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, 2006

Atomistic kinetic Monte Carlo simulations have been performed to illustrate the correlation between the Si interstitial defects generated by ion implantation, and B diffusion and activation in Si. The amount of residual damage is not very affected by moderate dynamic anneal during subamorphizing implants. However, dynamic anneal even at room temperature significantly influences the residual damage in amorphizing implants. The efficiency of the surface as a sink for point defects affects the evolution of Si interstitial defects. They set the Si interstitial supersaturation that is responsible for transient enhanced diffusion of B and also control the formation and dissolution of B-Si interstitial clusters.

Defects evolution and dopant activation anomalies in ion implanted silicon

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2006

The interactions between the defects and the implanted dopants are at the origin of the diffusion and activation anomalies that are among the major obstacles to the realisation of ultra-shallow junctions satisfying the ITRS requirements.