DocumentCode :
1065452
Title :
Moving Toward Nano-TCAD Through Multimillion-Atom Quantum-Dot Simulations Matching Experimental Data
Author :
Usman, Muhammad ; Hoon Ryu ; Insoo Woo ; Ebert, David S. ; Klimeck, Gerhard
Author_Institution :
Network for Comput. Nanotechnol., Electr. Eng. Dept., Purdue Univ., West Lafayette, IN
Volume :
8
Issue :
3
fYear :
2009
fDate :
5/1/2009 12:00:00 AM
Firstpage :
330
Lastpage :
344
Abstract :
Low-loss optical communication requires light sources at 1.5 mum wavelengths. Experiments showed, without much theoretical guidance, that InAs/GaAs quantum dots (QDs) may be tuned to such wavelengths by adjusting the In fraction in an InxGa1- xAs strain-reducing capping layer. In this paper, systematic multimillion-atom electronic structure calculations explain, qualitatively and quantitatively, for the first time, available experimental data. The nanoelectronic modeling NEMO 3-D simulations treat strain in a 15-million-atom system and electronic structure in a subset of ~ 9 million atoms using the experimentally given nominal geometries, and without any further parameter adjustments, the simulations match the nonlinear behavior of experimental data very closely. With the match to experimental data and the availability of internal model quantities, significant insight can be gained through mapping to reduced-order models and their relative importance. We can also demonstrate that starting from simple models has, in the past, led to the wrong conclusions. The critical new insight presented here is that the QD changes its shape. The quantitative simulation agreement with experiment, without any material or geometry parameter adjustment in a general atomistic tool, leads us to believe that the era of nanotechnology computer-aided design is approaching. NEMO 3-D will be released on nanoHUB.org, where the community can duplicate and expand on the results presented here through interactive simulations.
Keywords :
III-V semiconductors; band structure; gallium arsenide; indium compounds; nanoelectronics; semiconductor device models; semiconductor quantum dots; technology CAD (electronics); InAs-GaAs; NEMO 3D simulations; internal model quantities; low-loss optical communication; multimillion-atom electronic structure calculations; multimillion-atom quantum-dot simulations; nanoTCAD; nanoelectronic modeling; nanotechnology computer-aided design; reduced-order models; strain-reducing capping layer; wavelength 1.5 mum; Aspect ratio (AR); quantum dots (QDs); strain; strain reducing layer; wave function; wavelength;
fLanguage :
English
Journal_Title :
Nanotechnology, IEEE Transactions on
Publisher :
ieee
ISSN :
1536-125X
Type :
jour
DOI :
10.1109/TNANO.2008.2011900
Filename :
4749336
Link To Document :
بازگشت