Non-Silicon MOSFETs and Circuits with Atomic Layer Deposited Higher-k Dielectrics

<p>The quest for technologies beyond 14nm node complementary metal-oxide-semiconductor (CMOS) devices has now called for research on higher-k gate dielectrics integration with high mobility channel materials such as III-V semiconductors and germanium. Ternary oxides, such as La2-xYxO3 and LaAlO3, have been considered as strong candidates due to their high dielectric constants and good thermal stability. Meanwhile, the unique abilities of delivering large area uniform thin film, excellent controlling of composition and thickness to an atomic level, which are keys to ultra-scaled devices, have made atomic layer deposition (ALD) technique an excellent choice.</p> <p>In this thesis, we systematically study the atomic layer epitaxy (ALE) process realized by ALD, ALE higher-k dielectric integration, GaAs nMOSFETs and pMOSFETs on (111)A substrates, and their related CMOS digital logic gate circuits as well as ring oscillators. A record high drain current of 376 mA/mm and a small SS of 74 mV/dec are obtained from planar GaAs nMOSFETs with 1μm gate length. La2-xYxO3/GaAs(111)A interfaces are systematically investigated in both material and electrical aspects. The work has expanded the near 50 years GaAs MOSFETs research to an unprecedented level. Following the GaAs work, Ge n- and p-MOSFETs with epitaxial interfaces are also fabricated and studied. Beyond the conventional semiconductors, the complex oxide channel material SrTiO3 is also explored. Well-behaved LaAlO3/SrTiO3 nMOSFETs with a conducting channel at insulating ALD amorphous LaAlO3 - insulating crystalline SrTiO3 interface are also demonstrated.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Electrical and Computer Engineering

Year

2013

Author dc:creator

• Dong, Lin

Contributors dc:contributor

• Peide Ye
• David B. Janes
• Minghao QI
• Muhammad A. Alam

• applied sciences
• circuits
• cmos
• epitaxial interface
• gaas
• mosfets
• non-silicon
• Electrical and Computer Engineering
• Nanoscience and Nanotechnology

Repository record dc:identifier

https://docs.lib.purdue.edu/open_access_dissertations/203

OAI identifier oai:identifier

oai:docs.lib.purdue.edu:open_access_dissertations-1011