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oai:www.ideals.illinois.edu:2142/49679 2023-07-11 col_2142_5131 col_2142_14787 com_2142_5130 com_2142_9630 com_2142_234

King, William P. Koh, Youngjoon 2014-05-30T17:04:23Z 2014-05-30T17:04:23Z 2016-09-22T20:59:31Z 2014-05 2014-05-30T17:04:23Z 2014-05 This thesis reports the finite element modeling of a quantitative nanometer-scale temperature distribution along the doped Si devices. The modeling replicates data acquisition technique of Scanning Joule expansion microscopy (SJEM). Time varying heat equations and Maxwell’s equations are solved in frequency domain and applied to commercial finite element software, COMSOL. Chapter 1 introduces various techniques to obtain nanoscale temperature distribution. In Chapter 2, Joule heating and Thermoelectric heating in 1st harmonic and 2nd harmonic signals are analyzed by comparing the terms in governing equations and simulation results. Chapter 3 optimizes device design of doped Si and experimental conditions for future measurement. The approach used in Chapter 2 is expanded in Chapter 4 to understand thermoelectric behaviors in 500 nm thick boron doped p-type and phosphorus doped n-type Si devices with doping levels of 1019 cm-3 and 1018 cm-3. PtSi or NiSi Ohmic contacts are formed on the devices and thermoelectric behaviors are analyzed in conditions either under simultaneous DC and AC excitations, or AC only excitations. The simulation results show that thermoelectric contribution in heating increases with the product of electrical conductivity and Seebeck coefficient. Chapter 5 explains the future plan for the device fabrication and platform for contact resistance measurements. The studies in this thesis can extend to Schottky contact devices and further complicated structures for understanding heat and thermoelectric transport in specific frequency. Item withdrawn by Laura Spradlin (lspradl2@illinois.edu) on 2014-04-29T21:18:04Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Koh_Youngjoon.docx: 1184900 bytes, checksum: 03375e3ef74726f152a71f13f3f9eab1 (MD5) Koh_Youngjoon.pdf: 908528 bytes, checksum: dad7e90f3533f035c30d9c4c3fdfad0b (MD5) Made available in DSpace on 2014-05-30T17:04:23Z (GMT). No. of bitstreams: 3 Youngjoon_Koh.pdf: 908751 bytes, checksum: 68c3e30ad9eca769047869a855887b7b (MD5) Koh_Youngjoon.docx: 1184900 bytes, checksum: 03375e3ef74726f152a71f13f3f9eab1 (MD5) license.txt: 4060 bytes, checksum: 744e326472077965d994d5629834dfb3 (MD5) Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Seth Robbins (robbins.sd@gmail.com) on 2014-05-30T17:09:32Z Item is restricted until 2016-05-30T17:09:03Z Restriction data tranferred 2014-07-01T11:38:36-05:00 Original Data Group with Access UIUC Users [automated] Release Date: 2016-05-30 12:09:03 UTC Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only Restriction Lifted for Item 49730 on 2016-09-22T20:59:31Z. http://hdl.handle.net/2142/49679 en Copy right 2014 Youngjoon Koh Scanning Joule Expansion Microscopy Thermoelectric effect Joule heating COMSOL Thin film Si Modeling of Joule heating and thermoelectric transport in thin film silicon for SJEM measurement text Mechanical Sci & Engineering 1917 Mechanical Engineering 0133 University of Illinois at Urbana-Champaign Thesis M.S. MS:Mechanical Engineerng -UIUC 10KS0133MS