Wednesday, September 24, 2014

Monte Carlo Simulations of focused electron and ion beam induced processing


Monte Carlo simulations of focused ion beam induced processing

 R. Timilsina

Although several efforts are being devoted to understand the ion/electron-solid interactions and focused ion beam induced processing in the past several decades, the recent development of Gas Field Ion Source (GFIS) has garnered much attention in these days because of its wide range of applications in nanoscale synthesis, nanoscale imaging, lithography and nanofabrication. Timilsina et al have developed a simulator, called “EnvisION”, which has features of simulating elemental and compound targets by using both light and heavy ions with various beam profiles. The simulator can simulate electron/ion beams at different energies and provides the three dimensional nanostructures of deposited pillars, etched via and sputtered vias. In addition, the simulator calculates the nuclear and electronic energy loss profile, ion implant concentrations, resolution limiting effects etc. The peer-reviewed articles based on the EnvisION simulator and related to the simulator are listed below.

References

[1] R. Timilsina, D. A. Smith and P. D. Rack, “A comparison of neon versus helium ion beam induced deposition via Monte Carlo simulations”, Nanotechnology 24, 115302 (2013)
[2] R. Timilsina and P. D. Rack, “Monte Carlo Simulations of nanoscale focused neon ion beam sputtering”, Nanotechnology 24, 495303 (2013)
[3] R. Timilsina, S. Tan, R. Livengood and P. D. Rack, “Monte Carlo simulations of nanoscale focused neon ion beam sputtering of copper: elucidating resolution limits and sub-surface damage”, Nanotechnology 25, 485704 (2014)
[4] C. Gonzalez, R. Timilsina, G. Li, G. Duscher, P. D. Rack, W. Slingenbergh, W. F. van Dorp, J. T. M. De Hosson, K. L. Klein, H. M. Wu and L. A. Stern “Focused helium and neon ion beam induced etching for advanced extreme ultraviolet lithography mask repair”, J. Vac. Sci. Technol. B 32, 021602 (2014)
[5] H. M. Wu, L. A. Stern, J. H. Chen, M. Huth, C. H. Schwalb, M. Winhold, F. Porrati, C. M. Gonzalez, R. Timilsina and P. D. Rack, “Synthesis of nanowires via helium and neon focused ion beam induced deposition with the gas field ion microscope”, Nanotechnology 24, 175302 (2013)
[6] G. Arnold, R. Timilsina, J. Fowlkes, A. Orthacker, G. Kothleitner, P. D. Rack and H. Plank, “Fundamental Resolution Limits During Electron-Induced Direct-Write Synthesis”, ACS Applied material & interfaces, 6, 7380 (2014)
[7] J. H. Noh, J. D. Fowlkes, R. Timilsina, M. G. Stanford, B. B. Lewis and P. D. Rack, “Pulse Laser-Assisted focused electron-beam-induced etching of titanium with XeF2: Enhanced reaction rate and precursor transport”, ACS applied material & interfaces, 7, 4179 (2015)
[8] H. Guo, S. Dong, P. D. Rack, J. D. Budai, C. Beekman, Z. Gai, W. Siemons, C. M. Gonzalez, R. Timilsina, A. T. Wong, A. Herklotz, P. C. Snijders, E. Dagotto and T. Z. Ward, “Strain Doping: Reversible Single-Axis Control of a Complex Oxide Lattice via Helium Implantation”
[9] C. M. Gonzalez, W. Slingenbergh, R. Timilsina, J. H. Noh, M. G. Standford, B. B. Lewis, K. K. Klein, T. Liang, J. D. Fowlkes and P. D. Rack, “Evaluation of mask repair strategies via focused electron, helium, and neon beam induced processing for EUV applications ”, SPIE Proceeding, Extreme Ultraviolet (EUV) Lithography, 9048, 90480M (2014)

Sunday, January 29, 2012

Fascinating career for physicist "Quant"

I want to share you something that is very useful for the physicist who has strong background or willing to learn computer programming.
1. You learn basics of C++, Java and C# (c sharp)
2. Numerical methods such as ODE, PDE, Monte Carlo Simulation
3. Data analysis skills
4. Parallel programming such as OpenMPI

I will provide basic tutorials on each topic so that I would be helpful to you.

Thursday, July 7, 2011

Who is smart? A professor or students

That was on Tuesday, three friends decided to attend a wedding party of their friend, however, they have a test on the next day. They went to the party and stayed over there the whole night. They have the test on the morning at 11 am. They were not prepared enough, so they made a plan. They will tell the professor that they went to a wedding party just for two hours but a tire of their car got flat in the middle of a way going back to their home. It was in the midnight so that they couldn't find anyone nearby them and they pushed the car unless they could reach their home. They put some mud and oil on the cloths and went to the professor. They told according to the plan and requested him to postpone the test for the next day.  The professor told them that why only one day, he will give them 3 more days and the test will be on Friday morning. They were so happy and went to the home and did good preparation for the test.

On Friday, the professor told them to be in three different rooms. The professor asked them only two questions which are given below.

1)    Write your name                  (5 Marks)

2)     Which tire got flat?             (95 Marks)

Now it's your turn, who is smart?
Students or the professor?