@article{NeuperCadilhaMarquesSingarajuetal.2020, author = {Felix Neuper and Gabriel Cadilha Marques and Surya Abhishek Singaraju and Robert Kruk and Jasmin Aghassi-Hagmann and Horst Hahn and Ben Breitung}, title = {ALD-Derived, Low-Density Alumina as Solid Electrolyte in Printed Low-Voltage FETs}, series = {IEEE Transactions on Electron Devices}, volume = {67}, number = {9}, organization = {IEEE}, issn = {0018-9383 (Print)}, doi = {10.1109/TED.2020.3005624}, pages = {3828 -- 3833}, year = {2020}, abstract = {In this report, we have studied field-effect transistors (FETs) using low-density alumina for electrolytic gating. Device layers have been prepared starting from the structured ITO glasses by printing the In 2 O 3 channels, low-temperature atomic layer deposition (ALD) of alumina (Al 2 O 3 ), and printing graphene top gates. The transistor performance could be deliberately changed by alternating the ambient humidity; furthermore, ID,ON/ID,OFF-ratios of up to seven orders of magnitude and threshold voltages between 0.66 and 0.43 V, decreasing with an increasing relative humidity between 40\% and 90\%, could be achieved. In contrast to the common usage of Al 2 O 3 as the dielectric in the FETs, our devices show electrolyte-typegating behavior. This is a result from the formation of protons on the Al 2 O 3 surfaces at higher humidities. Due to the very high local capacitances of the Helmholtz double layers at the channel surfaces, the operation voltage can be as low as 1 V. At low humidities (≤30\%), the solid electrolyte dries out and the performance breaks down; however, it can fully reversibly be regained upon a humidity increase. Using ALD-derived alumina as solid electrolyte gating material, thus, allows low-voltage operation and provides a chemically stable gating material while maintaining low process temperatures. However, it has proven to be highly humidity-dependent in its performance.}, language = {en} }