The Wonderful World of Designer Germanium Quantum Dots for CMOS Integrable Quantum Devices
Title： The Wonderful World of Designer Germanium Quantum Dots for CMOS Integrable Quantum Devices
Time：Nov. 12, 2021, 14:30~15:30
Place：Rm104: Chin-Pao Yang Lecture Hall, CCMS & New Physics Building, NTU
Abstract:
Cutting-edge research on Si-based quantum dots (QDs) has opened up access to wide-ranging applications in electronics, photonics, quantum computing, and sensing. The “holy grail” for device manufacturers is to achieve scalability through precise control and repeatable fabrication of QDs with desired shapes, sizes, and ac-curate placement for predictable electrical and optical proper-ties. A Bohr radius of 5 nm in Si dictates the fabrication of ultrasmall Si QDs, which are difficult to controllably produce using either self-assembly or lithographic techniques. In contrast, a large Bohr radius of 25nm in Ge enables easier modification of electronic structures using Ge QDs, imposing less stringent demands on lithographic control.
Starting with our remarkable discovery of spherical germanium (Ge) QD formation, we have embarked on an exciting journey of further discovery, all the while maintaining CMOS-compatible processes. We have taken advantage of the many peculiar and symbiotic interactions of Si, Ge and O interstitials to create a novel portfolio of electronic, photonic and quantum computing devices. This paper summarizes several of these completely new and counter-intuitive accomplishments. Using a coordinated combination of lithographic patterning and self-assembly, size-tunable spherical Ge QDs were controllably placed at designated spatial locations within Si-containing layers. We exploited the exquisite control available through the thermal oxidation of Si1-xGex patterned structures in proximity to Si3N4/Si layers. Our so-called “designer” Ge QDs have succeeded in opening up myriad device possibilities, including paired QDs for qubits, single-hole transistors (SHTs) for charge sensing, photodetectors and light-emitters for Si photonics, and junctionless (JL) FETs using standard Si processing.
Time：Nov. 12, 2021, 14:30~15:30
Place：Rm104: Chin-Pao Yang Lecture Hall, CCMS & New Physics Building, NTU
Abstract:
Cutting-edge research on Si-based quantum dots (QDs) has opened up access to wide-ranging applications in electronics, photonics, quantum computing, and sensing. The “holy grail” for device manufacturers is to achieve scalability through precise control and repeatable fabrication of QDs with desired shapes, sizes, and ac-curate placement for predictable electrical and optical proper-ties. A Bohr radius of 5 nm in Si dictates the fabrication of ultrasmall Si QDs, which are difficult to controllably produce using either self-assembly or lithographic techniques. In contrast, a large Bohr radius of 25nm in Ge enables easier modification of electronic structures using Ge QDs, imposing less stringent demands on lithographic control.
Starting with our remarkable discovery of spherical germanium (Ge) QD formation, we have embarked on an exciting journey of further discovery, all the while maintaining CMOS-compatible processes. We have taken advantage of the many peculiar and symbiotic interactions of Si, Ge and O interstitials to create a novel portfolio of electronic, photonic and quantum computing devices. This paper summarizes several of these completely new and counter-intuitive accomplishments. Using a coordinated combination of lithographic patterning and self-assembly, size-tunable spherical Ge QDs were controllably placed at designated spatial locations within Si-containing layers. We exploited the exquisite control available through the thermal oxidation of Si1-xGex patterned structures in proximity to Si3N4/Si layers. Our so-called “designer” Ge QDs have succeeded in opening up myriad device possibilities, including paired QDs for qubits, single-hole transistors (SHTs) for charge sensing, photodetectors and light-emitters for Si photonics, and junctionless (JL) FETs using standard Si processing.
