{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/69528"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/69528","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Systems of Nonlinear Algebraic Equations Arising in Simulation of Semiconductor Devices","abstract":"In this thesis we present several formulations of the system of elliptic partial differential equations that model a semiconductor device. We use standard finite difference methods to discretize these equations and derive systems of nonlinear equations. Due to the extremely large number of unknowns it is prohibitively expensive to use Newton's method. However, the Jacobians of these systems are relatively simple to compute. Hence, it is practical to exploit the properties of these systems and develop a class of Newton-like methods based on splittings of the Jacobians. We state and prove sufficient conditions on device parameters for convergence of these methods.","abstract_html":"In this thesis we present several formulations of the system of elliptic partial differential equations that model a semiconductor device. We use standard finite difference methods to discretize these equations and derive systems of nonlinear equations. Due to the extremely large number of unknowns it is prohibitively expensive to use Newton's method. However, the Jacobians of these systems are relatively simple to compute. Hence, it is practical to exploit the properties of these systems and develop a class of Newton-like methods based on splittings of the Jacobians. We state and prove sufficient conditions on device parameters for convergence of these methods.","abstract_has_math":false,"creators":["Sheikh, Qasim Mohammad"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Computer Science","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T19:25:31Z","date_published":"2014-12-15T19:25:31Z","updated_at":"2026-07-22T22:26:01Z","subjects":["Computer Science"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8410047"],"render_values":[{"text":"(UMI)AAI8410047","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/69528","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Sheikh, Qasim Mohammad"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T19:25:31Z","10000-01-01","1983"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Computer Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Computer Science"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/69528","(UMI)AAI8410047"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["In this thesis we present several formulations of the system of elliptic partial differential equations that model a semiconductor device. We use standard finite difference methods to discretize these equations and derive systems of nonlinear equations. Due to the extremely large number of unknowns it is prohibitively expensive to use Newton's method. However, the Jacobians of these systems are relatively simple to compute. Hence, it is practical to exploit the properties of these systems and develop a class of Newton-like methods based on splittings of the Jacobians. We state and prove sufficient conditions on device parameters for convergence of these methods.","We also describe a multigrid method for solving these systems. Several multigrid methods for solving such systems are available in the literature. The most common approach for solving the nonlinear system is to first linearize the system and then use a multigrid method to solve this linear system. We apply the multigrid method directly to the nonlinear system. This approach gives us a nonlinear system to be solved at each grid. Our approach enables us to blend the multigrid method and the point Gauss-Seidel-Newton method. We give numerical examples to compare this method and the Newton-like methods.","Made available in DSpace on 2014-12-15T19:25:31Z (GMT). No. of bitstreams: 1 8410047.pdf: 1513140 bytes, checksum: 6407eea86b433b30fa80832aaf3dfd82 (MD5) Previous issue date: 1983","Embargo set by: Seth Robbins for item 69694 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","62 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1983."]},{"key":"dc:title","label":"Title","values":["Systems of Nonlinear Algebraic Equations Arising in Simulation of Semiconductor Devices"]}]}],"canonical_facts":{"dc:creator":["Sheikh, Qasim Mohammad"],"dc:date":["2014-12-15T19:25:31Z","10000-01-01","1983"],"dc:description":["In this thesis we present several formulations of the system of elliptic partial differential equations that model a semiconductor device. We use standard finite difference methods to discretize these equations and derive systems of nonlinear equations. Due to the extremely large number of unknowns it is prohibitively expensive to use Newton's method. However, the Jacobians of these systems are relatively simple to compute. Hence, it is practical to exploit the properties of these systems and develop a class of Newton-like methods based on splittings of the Jacobians. We state and prove sufficient conditions on device parameters for convergence of these methods.","We also describe a multigrid method for solving these systems. Several multigrid methods for solving such systems are available in the literature. The most common approach for solving the nonlinear system is to first linearize the system and then use a multigrid method to solve this linear system. We apply the multigrid method directly to the nonlinear system. This approach gives us a nonlinear system to be solved at each grid. Our approach enables us to blend the multigrid method and the point Gauss-Seidel-Newton method. We give numerical examples to compare this method and the Newton-like methods.","Made available in DSpace on 2014-12-15T19:25:31Z (GMT). No. of bitstreams: 1 8410047.pdf: 1513140 bytes, checksum: 6407eea86b433b30fa80832aaf3dfd82 (MD5) Previous issue date: 1983","Embargo set by: Seth Robbins for item 69694 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","62 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1983."],"dc:identifier":["http://hdl.handle.net/2142/69528","(UMI)AAI8410047"],"dc:subject":["Computer Science"],"dc:title":["Systems of Nonlinear Algebraic Equations Arising in Simulation of Semiconductor Devices"],"dc:type":["text"],"thesis:degree_discipline":["Computer Science"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:01Z"}