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This study investigates the electrical characteristics observed in n-channel and p-channel ferroelectric field effect transistor (FeFET) devices fabricated through a similar process flow with 10 nm of ferroelectric hafnium zirconium oxide (HZO) as the gate dielectric. The n-FeFETs demonstrate a faster complete polarization switching compared to the p-channel counterparts. Detailed and systematic investigations using TCAD simulations reveal the role of fixed charges and interface traps at the HZO-interfacial layer (HZO/IL) interface in modulating the subthreshold characteristics of the devices. A characteristic crossover point observed in the transfer characteristics of n-channel devices is attributed with the temporary switching between ferroelectric-based operation to charge-based operation, caused by the pinning effect due to the presence of different traps. This experimental study helps understand the role of charge trapping effects in switching characteristics of n- and p-channel ferroelectric FETs.
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This content will become publicly available on July 22, 2026
Silicon Microring Resonator Integrated Hafnium Zirconium Oxide Ferrophotonic Non-Volatile Memory
We experimentally demonstrate the heterogeneous integration of ferroelectric hafnium zirconium oxide (HZO) with a silicon photonic microring resonator and demonstrate two non-volatile states for data storage by switching the polarization of HZO. Capped by transparent conducting titanium doped indium oxide (ITiO), the device functions as a metal insulator semiconductor (MIS) capacitor and utilizes the refractive index modulation via carrier (hole) accumulation and the effect of trapped charges at the ferroelectric–silicon interface to create the non-volatile binary switching states. In contrast to electronic devices where trapped charges at the silicon–ferroelectric interface reduce the memory window, in our ferrophotonic device, trapped charges amplify the refractive index difference in the binary states due to effective screening of the silicon in inversion. By switching the applied bias from negative to positive, the optical power transmitted through the ring switches with 3.5 dB output power difference between the non-volatile set and reset states and 40 pJ switching energy at ±8 V. Preliminary results suggest a path toward achieving sub-1 V non-volatile ferrophotonic switching.
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- Award ID(s):
- 2315085
- PAR ID:
- 10630473
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- ACS Photonics
- Volume:
- 12
- Issue:
- 8
- ISSN:
- 2330-4022
- Page Range / eLocation ID:
- 4524 to 4533
- Subject(s) / Keyword(s):
- silicon photonics microring resonator hafnium zirconium oxide ferroelectrics ferrophotonics non-volatile memory
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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