Band-bending and induced junctions of silicon heterojunction solar cells
| Author(s) | Hack, James Henry | |
| Date Accessioned | 2021-05-25T13:12:08Z | |
| Date Available | 2021-05-25T13:12:08Z | |
| Publication Date | 2021 | |
| SWORD Update | 2021-03-19T01:02:18Z | |
| Abstract | Solar cells, a critical part of an emerging renewable energy mix, rely on efficiently absorbing light and extracting the energy of that light in the form of electricity. This extraction relies on charge separation, enabled by the creation of a semiconductor p-n junction, and on limiting pathways of energy loss through passivation of bulk defects and material interfaces. Treatment of silicon surfaces can act both to passivate the surface and also to form a junction within the silicon. These effects are linked to bending of the energy bands of the crystalline silicon. This work investigates passivation and junction inducing effects of organic and amorphous Si layers on silicon wafers for photovoltaic applications. In this work, capacitance-voltage and surface photovoltage techniques are applied and compared for the measurement of built-in potential of silicon heterojunctions. The role of inversion layer formation in CV measurement saturation is explained in new detail. Surface photovoltage techniques using scanning Kelvin probe microscopy and X-ray photoemission spectroscopy are used to measure the band-bending occurring on benzoquinone treated surfaces, indicating a strong downward band-bending. Hybrid solar cell devices using PEDOT:PSS on crystalline silicon are fabricated and characterized, enabling an increase in efficiency of such devices from 5 to 12%. The contact resistivity of Ag on PEDOT:PSS is indicated to be less than 0.017 Ohm*cm^2. The importance of back-side passivation for these devices was quantified, with a 58mV and 128mV Voc gain for devices BSF and a-Si structures, relative to unpassivated back contacts. | en_US |
| Advisor | Opila, Robert L. | |
| Degree | Ph.D. | |
| Department | University of Delaware, Department of Materials Science and Engineering | |
| DOI | https://doi.org/10.58088/3h6t-dz13 | |
| Unique Identifier | 1252716465 | |
| URL | https://udspace.udel.edu/handle/19716/29004 | |
| Language | en | |
| Publisher | University of Delaware | en_US |
| URI | https://login.udel.idm.oclc.org/login?url=https://www.proquest.com/dissertations-theses/band-bending-induced-junctions-silicon/docview/2507962523/se-2?accountid=10457 | |
| Keywords | Band bending | |
| Keywords | Induced junctions | |
| Keywords | Photovoltaics | |
| Keywords | Silicon heterojunction | |
| Keywords | Solar cells | |
| Title | Band-bending and induced junctions of silicon heterojunction solar cells | en_US |
| Type | Thesis | en_US |