http://hdl.handle.net/10468/3240 2017-10-30T17:57:53Z 2017-10-30T17:57:53Z Long, Brenda Verni, Giuseppe A. O'Connell, John Holmes, Justin D. Shayesteh, Maryam O'Connell, Dan Duffy, Ray http://hdl.handle.net/10468/2412 2017-08-22T15:06:13Z 2014-06-01T00:00:00Z

Molecular layer doping: non-destructive doping of silicon and germanium Long, Brenda; Verni, Giuseppe A.; O'Connell, John; Holmes, Justin D.; Shayesteh, Maryam; O'Connell, Dan; Duffy, Ray This work describes a non-destructive method to introduce impurity atoms into silicon (Si) and germanium (Ge) using Molecular Layer Doping (MLD). Molecules containing dopant atoms (arsenic) were designed, synthesized and chemically bound in self-limiting monolayers to the semiconductor surface. Subsequent annealing enabled diffusion of the dopant atom into the substrate. Material characterization included assessment of surface analysis (AFM) and impurity and carrier concentrations (ECV). Record carrier concentration levels of arsenic (As) in Si (~5Ã 10^20 atoms/cm3) by diffusion doping have been achieved, and to the best of our knowledge this work is the first demonstration of doping Ge by MLD. Furthermore due to the ever increasing surface to bulk ratio of future devices (FinFets, MugFETs, nanowire-FETS) surface packing spacing requirements of MLD dopant molecules is becoming more relaxed. It is estimated that a molecular spacing of 2 nm and 3 nm is required to achieve doping concentration of 10^20 atoms/cm3 in a 5 nm wide fin and 5 nm diameter nanowire respectively. From a molecular perspective this is readily achievable.

2014-06-01T00:00:00Z Rohan, James F. Hasan, Maksudul Patil, Sanjay Casey, Declan P. Clancy, Tomás http://hdl.handle.net/10468/1650 2016-11-03T12:01:00Z 2014-02-01T00:00:00Z

Energy storage: battery materials and architectures at the nanoscale Rohan, James F.; Hasan, Maksudul; Patil, Sanjay; Casey, Declan P.; Clancy, Tomás

2014-02-01T00:00:00Z Schmidt, Michael Nazneen, F. Galvin, Paul Petkov, Nikolay Holmes, Justin D. http://hdl.handle.net/10468/2468 2016-04-21T02:00:12Z 2013-12-06T00:00:00Z

FIB patterning of stainless steel for the development of nano-structured stent surfaces for cardiovascular applications Schmidt, Michael; Nazneen, F.; Galvin, Paul; Petkov, Nikolay; Holmes, Justin D. Wang, M. Z. Stent implantation is a percutaneous interventional procedure that mitigates vessel stenosis, providing mechanical support within the artery and as such a very valuable tool in the fight against coronary artery disease. However, stenting causes physical damage to the arterial wall. It is well accepted that a valuable route to reduce in-stent re-stenosis can be based on promoting cell response to nano-structured stainless steel (SS) surfaces such as by patterning nano-pits in SS. In this regard patterning by focused ion beam (FIB) milling offers several advantages for flexible prototyping. On the other hand FIB patterning of polycrystalline metals is greatly influenced by channelling effects and redeposition. Correlative microscopy methods present an opportunity to study such effects comprehensively and derive structure–property understanding that is important for developing improved patterning. In this chapter we present a FIB patterning protocol for nano-structuring features (concaves) ordered in rectangular arrays on pre-polished 316L stainless steel surfaces. An investigation based on correlative microscopy approach of the size, shape and depth of the developed arrays in relation to the crystal orientation of the underlying SS domains is presented. The correlative microscopy protocol is based on cross-correlation of top-view scanning electron microscopy, electron backscattering diffraction, atomic force microscopy and cross-sectional (serial) sectioning. Various FIB tests were performed, aiming at improved productivity by preserving nano-size accuracy of the patterned process. The optimal FIB patterning conditions for achieving reasonably high throughput (patterned rate of about 0.03 mm2/h) and nano-size accuracy in dimensions and shapes of the features are discussed as well.

2013-12-06T00:00:00Z Chowdhury, Tamjid Rohan, James F. http://hdl.handle.net/10468/1653 2016-11-03T12:01:00Z 2013-05-01T00:00:00Z

Carbon nanotube composites for electronic interconnect applications Chowdhury, Tamjid; Rohan, James F. Suzuki, Satoru

2013-05-01T00:00:00Z