Abstract Transparent oxide thin film transistors (TFTs) are an important ingredient of transparent electronics. Their fabrication at the back‐end‐of‐line (BEOL) opens the door to novel strategies to more closely integrate logic with memory for data‐intensive computing architectures that overcome the scaling challenges of today's integrated circuits. A recently developed variant of molecular‐beam epitaxy (MBE) called suboxide MBE (S‐MBE) is demonstrated to be capable of growing epitaxial In2O3at BEOL temperatures with unmatched crystal quality. The fullwidth at halfmaximum of the rocking curve is 0.015° and, thus, ≈5x narrower than any reports at any temperature to date and limited by the substrate quality. The key to achieving these results is the provision of an In2O beam by S‐MBE, which enables growth in adsorption control and is kinetically favorable. To benchmark this deposition method for TFTs, rudimentary devices were fabricated.
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Molecular beam epitaxy for oxide electronics
The ability to synthesize new materials with unique functionalities has provided the foundation for modern electronics and for new discoveries. Oxide molecular beam epitaxy (MBE) has played a vital role in this endeavor. In this chapter, key fundamental concepts discussing the physics of complex oxides, followed by the important role of oxide MBE, are presented. Recent technical advances, current and potential challenges, and advantages of an oxide MBE are reviewed. Important factors responsible for electronic-quality oxide films – including of those metals that are difficult to oxidize – are discussed, with particular emphasis on new developments with radical-based MBE approaches. Taking analogy from III–V MBE, the current status and future prospects of oxide MBE are discussed in developing oxide electronics operating at room temperature.
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- Award ID(s):
- 1420013
- PAR ID:
- 10310102
- Date Published:
- Journal Name:
- Wiley series in materials for electronic and optoelectronic applications
- ISSN:
- 1937-4003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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