Middle Electrode in a Vertical Transistor Structure Using an Sn Layer by Thermal Evaporation

Author(s)

Nogueira, Gabriel Leonardo ^[1] ; Ozorio, Maiza da Silva ^[1] ; da Silva, Marcelo Marques ^[1] ; Morais, Rogerio Miranda ^[1] ; Alves, Neri ^[1]

Affiliation

^[1] Sao Paulo State Univ UNESP, Sch Technol & Appl Sci, BR-19060900 Presidente Prudente, SP - Brazil

• Document type: Journal article
• Source: ELECTRONIC MATERIALS LETTERS; v. 14, n. 3, p. 319-327, MAY 2018.
• Web of Science Citations: 0

Abstract

We report a process for performing the middle electrode for a vertical field effect transistor (VOFET) by the evaporation of a tin (Sn) layer. Bare aluminum oxide (Al2O3), obtained by anodization, and Al2O3 covered with a polymethylmethacrylate (PMMA) layer were used as the gate dielectric. We measured the electrical resistance of Sn while the evaporation was carried out to find the best condition to prepare the middle electrode, that is, good lateral conduction associated with openings that give permeability to the electric field in a vertical direction. This process showed that 55 nm Sn thick is suitable for use in a VOFET, being easier to achieve optimal thickness when the Sn is evaporated onto PMMA than onto bare Al2O3. The addition of a PMMA layer on the Al2O3 surface modifies the morphology of the Sn layer, resulting in a lowering of the threshold voltage. The values of threshold voltage and electric field, V-TH = - 8 V and E-TH = 354.5 MV/m respectively, were calculated using an Al2O3 film 20 nm thick covered with a 14 nm PMMA layer as gate dielectric, while for bare Al2O3 these values were V-TH = - 10 V and E-TH = 500 MV/m. {[}GRAPHICS] . (AU)

• FAPESP's process: 13/26973-5 - Preparation and characterization of an organic field effect transistor using a vertical architecture
• Grantee: Gabriel Leonardo Nogueira
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 14/13015-9 - Development of thin film transistors for printed inverter circuits on flexible substrates
• Grantee: Neri Alves
• Support Opportunities: Regular Research Grants