Department
Physics
Major
Physics
Research Advisor
Medvedeva, Julia
Advisor's Department
Physics
Funding Source
DOE-EERE-SETO Program; NSF-FuSE Program, potentially
Abstract
For decades, n-type transparent conducting oxides (TCOs) have been extensively studied and applied in various energy and optoelectronic devices. However, the search for high-performance p-type TCOs, crucial for transparent p-n junctions and next-generation microelectronics - remains uncertain. The most studied p-type TCOs (e.g ., Cu2O-based delafossite family) exhibit the carrier mobilities (<1 cm2Ns) that are much smaller than those in typical n-type TCOs (10-100 cm2Ns). In contrast to the Cu-based layered materials with a relatively flat Cu d10 valence band (resulting in the hole effective mass of 2.5me), Sn2+ in SnO has s2 electronic configuration giving rise to a significantly more dispersed valence band (the hole effective mass is 0.5me) and, hence, to higher hole mobility. Currently, the practical use of SnO is limited due to (i) stability issues of SnO associated with tin preference for valence 4 (as in SnO2, a well-known n-type TCO); (ii) small band gap ~0.7 eV; and (iii) anisotropic hole effective mass in the crystalline phase. Further search for p-type TCOs should involve amorphous phases of SnO-based multi-cation materials where metal composition helps stabilize Sn2+ and open the band gap, whereas the disordered structure is expected to result in uniform isotropic electronic properties and low scattering due to absence of grain boundaries.
Biography
Joshua Santy is a junior at Missouri S& T double majoring in Physics and Applied Mathematics. His passion for Physics and research led him to collaborate with Dr. Medvedeva, exploring the structure and electronic properties of Amorphous Tin Oxide for CMOS Applications. Josh enjoys programming in Python and bash scripting for his research, as well as participating in coding competitions such as PickHacks. Beyond his academic pursuits, Joshua is an Officer of the Society of Physics Students at S& T. Additionally, he actively contributes as a member and media team participant for the Christian Campus Fellowship. Moreover, he is a member of the S& T Symphonic Orchestra.
Research Category
Sciences
Presentation Type
OURE Fellows Proposal Oral Applicant
Document Type
Presentation
Location
Havener Center - Carver Room
Presentation Date
10 April 2024, 1:00 pm - 4:00 pm
Included in
Amorphous Transparent Oxide P-type Semiconductors
Havener Center - Carver Room
For decades, n-type transparent conducting oxides (TCOs) have been extensively studied and applied in various energy and optoelectronic devices. However, the search for high-performance p-type TCOs, crucial for transparent p-n junctions and next-generation microelectronics - remains uncertain. The most studied p-type TCOs (e.g ., Cu2O-based delafossite family) exhibit the carrier mobilities (<1 >cm2Ns) that are much smaller than those in typical n-type TCOs (10-100 cm2Ns). In contrast to the Cu-based layered materials with a relatively flat Cu d10 valence band (resulting in the hole effective mass of 2.5me), Sn2+ in SnO has s2 electronic configuration giving rise to a significantly more dispersed valence band (the hole effective mass is 0.5me) and, hence, to higher hole mobility. Currently, the practical use of SnO is limited due to (i) stability issues of SnO associated with tin preference for valence 4 (as in SnO2, a well-known n-type TCO); (ii) small band gap ~0.7 eV; and (iii) anisotropic hole effective mass in the crystalline phase. Further search for p-type TCOs should involve amorphous phases of SnO-based multi-cation materials where metal composition helps stabilize Sn2+ and open the band gap, whereas the disordered structure is expected to result in uniform isotropic electronic properties and low scattering due to absence of grain boundaries.
