Perovskite is frequently touted as a promising electronics material for optoelectronics applications. Materials researchers this week reported an advance by fabricating thin films based on perovskite semiconductors that yielded substrates with tunable electronic properties.
That, the researchers assert, could expand use of the silicon alternative in future electronic devices.
Researchers at Gwangju Research Institute of Science and Technology in South Korea said their thin films are based on a substrate frequently used to grow oxide films, strontium titanate, or SrTiO3. The perovskite structure features a high dielectric constant.
The investigators said they observed changes in the substrate surface without interference from dopants. “The presence of doping can interfere with correct interpretation of the surface defect states, which can be critical to [determining] the electrical properties of heterostructures,” said lead researcher Bongjin Simon Mun.
As a result, the researchers said they were able to gauge the “unbiased characteristics of SrTiO3 substrate.”
The Gwangju researchers used ambient pressure X-ray photoelectron spectroscopy and low-energy electron diffraction to determine how fabrication techniques affect SrTiO3. Along with examining effects on the undoped surfaced, they also looked at the resulting interface layer of the heterostructure.
“Our work shows clearly how the electrical properties of devices can be tuned by adjusting the population of electrons near the surface region, which is a very fundamental and important result indicating that future electronic devices can be realized with material characterization at the atomic level,” Mun said.
In a research paper published in the Journal of Materials Chemistry C, the investigators said their findings “suggest that the surface electronic structure of the substrate has a greater influence on the properties of complex oxide heterostructures than other parameters.”
“In the long run, our study on SrTiO3 will lay out a solid foundation for advanced electronic devices,” Mun asserted.
Devices based on perovskite could include photovoltaic cells that combine the material with silicon along with single- and multi-junction photovoltaics, new light-emitting diodes and thin films used for quantum dot color conversion and enhancement.
There are “extensive opportunities for innovative organic semiconductors across multiple applications,” market tracker IDTechX noted in a recent survey of emerging electronics materials.