Molecular dynamics simulation of surface deformation via Ar+ ion collision process

Luo²,

Jiang

et al. 2016

CNANO

Background: Although various advanced FIB processing methods for the fabrication of 3D nanostructures have been successfully developed by many researchers, the FIB milling has an unavoidable result in terms of the implantation of ion source materials and the formation of damaged layer at the near surface. Understanding the ion-solid interactions physics provides a unique way to control the FIB produced defects in terms of their shape and location. Methods:We have carefully selected peer-reviewed papers which mainly focusing on the review questions of this paper. A deductive content analysis method was used to analyse the methods, findings and conclusions of these papers. Based on their research methods, we classify their works in different groups. The theory of ion-matter interaction and the previous investigation on ion-induced damage in diamond were reviewed and discussed. Results:The previous research work has provided a systematic analysis of ion-induced damage in diamond. Both experimental and simulation methods have been developed to understand the damage process. The damaged layers created in FIB processing process can significantly degrade/alter the device performance and limit the applications of FIB nanofabrication technique. There are still challenges involved in fabricating large, flat, and uniform TEM samples in undoped non-conductive diamond. Conclusions:The post-facto-observation leaves a gap in understanding the formation process of ion-induced damage, forcing the use of assumptions. In contrast, MD simulations of ion bombardment have shed much light on ion beam mixing for decades. These activities make it an interesting and important task to understand what the fundamental effects of energetic particles on matter are.

Section: Figure 10mentioning

confidence: 99%

Review on FIB-Induced Damage in Diamond Materials

Luo²,

Jiang

et al. 2016

CNANO

“…In recent years, the rapid progress in developing the computer power capacity, particularly the development of cluster parallel computing technique, has largely increased the size of MD computing domain and enabled the promised elucidation of multi-particle collision processes. Some newly developed three-dimensional models are emerging to address the ion-induced damage and thermal annealing process [27,28], and the effects of ion fluence [29,30] and incident angle [31] on the structure and properties of target materials. Large-scale MD computational domain and a combination of ZBL (Ziegler, Biersack and Littmark) and Tersoff potential functions have been reported to help express accurately the stopping of incident ions and the fully track of thermal spike [32,33].…”

Section: Introductionmentioning

confidence: 99%

Investigation of focused ion beam induced damage in single crystal diamond tools

Applied Surface Science

Luo

2015

In this work, transmission electron microscope (TEM) measurements and molecular dynamics (MD) simulations were carried out to characterise the focused ion beam (FIB) induced damage layer in a single crystal diamond tool under different FIB processing voltages. The results obtained from the experiments and the simulations are in good agreement. The results indicate that during FIB processing cutting tools made of natural single crystal diamond, the energetic Ga + collision will create an impulse-dependent damage layer at the irradiated surface. For the tested beam voltages in a typical FIB system (from 8 kV to 30 kV), the thicknesses of the damaged layers formed on a diamond tool surface increased from 11.5 nm to 27.6 nm. The dynamic damage process of FIB irradiation and ion-solid interactions physics leading to processing defects in FIB milling were emulated by MD simulations. The research findings from this study provide the in-depth understanding of the wear of nanoscale multi-tip diamond tools considering the FIB irradiation induced doping and defects during the tool fabrication process.

“…Satake et al [28] reported to help express accurately the stopping of incident ions [28] and the fully track of the thermal spike [29]. Recently, the effects of ion fluence and acceleration energy of incident ion on the Si surface deformation have also been reported [30,31]. These activities make it an interesting and important task to understand the fundamental effects of energetic particles on matter.…”

Section: Introductionmentioning

confidence: 99%

Molecular dynamic simulation of low-energy FIB irradiation induced damage in diamond

Nuclear Instruments and Methods in Physics Research Section B:

et al. 2015

In this article, a large scale multi-particle molecular dynamics (MD) simulation model was developed to study the dynamic structural changes in single crystal diamond under 5 keV Ga + irradiation in conjunction with a transmission electron microscopy (TEM) experiment. The results show that the thickness of ion-induced damaged layer (~ 9.0 nm)obtained from experiments and simulations has good accordance, which demonstrates the high accuracy achieved by the developed MD model. Using this model, the evolution of atomic defects, the spatial distributions of implanted Ga particles the thermal spike at the very core collision area were analysed. The local thermal recrystallizations observed during each single ion collision process and the increase of the density of the non-diamond phase (mostly sp 2 bonded) at irradiation area are fund to be the underling mechanisms responsible for ion fluence dependent amorphization of diamond observed in previous experiments.