Room-temperature fabricated, fully transparent resistive memory based on ITO/CeO2/ITO structure for RRAM applications

• Fully transparent resistive random access memory (TRRAM) device based on CeO2.
• ITO/CeO2/ITO device shows ~81% transmission in the visible region from 400–700 nm.
• Bipolar RS>100 cycles, low bias, stable distribution of switching characteristic.
• Ohmic and Poole–Frenkel conductions play dominant role.
• Switching mechanism involves formation/rupture of filaments made of O2 vacancies.

Fully transparent resistive random access memory (TRRAM) device based on CeO2 as active layer using indium-tin-oxide (ITO) electrodes was fabricated on glass substrate. The ITO/CeO2/ITO memory device shows 81% transmission of visible light, optical band gap energy of 4.05 eV, and exhibits reliable bipolar resistive switching behavior. X-ray diffraction of CeO2 thin films demonstrated a weak polycrystalline phase. The low field conduction is dominated by Ohmic type while Poole–Frenkel effect is responsible for conduction in the high field region. The device reliability investigations, such as data retention (over 104 s) under applied stress and endurance tests conducted at room temperature and 85 °C show potential of our TRRAM devices for future non-volatile memory applications.