摘要:
A method of fabricating quantum confinements is provided. The method includes depositing, using a deposition apparatus, a material layer on a substrate, where the depositing includes irradiating the layer, before a cycle, during a cycle, and/or after a cycle of the deposition to alter nucleation of quantum confinements in the material layer to control a size and/or a shape of the quantum confinements. The quantum confinements can include quantum wells, nanowires, or quantum dots. The irradiation can be in-situ or ex-situ with respect to the deposition apparatus. The irradiation can include irradiation by photons, electrons, or ions. The deposition is can include atomic layer deposition, chemical vapor deposition, MOCVD, molecular beam epitaxy, evaporation, sputtering, or pulsed-laser deposition.
摘要:
A method of making nanowire probes is provided. The method includes providing a template having a nanoporous structure, providing a probe tip that is disposed on top of the template, and growing nanowires on the probe tip, where the nanowires are grown from the probe tip along the nanopores, and the nanowires conform to the shape of the nanopores.
摘要:
A method of fabricating quantum confinements is provided. The method includes depositing, using a deposition apparatus, a material layer on a substrate, where the depositing includes irradiating the layer, before a cycle, during a cycle, and/or after a cycle of the deposition to alter nucleation of quantum confinements in the material layer to control a size and/or a shape of the quantum confinements. The quantum confinements can include quantum wells, nanowires, or quantum dots. The irradiation can be in-situ or ex-situ with respect to the deposition apparatus. The irradiation can include irradiation by photons, electrons, or ions. The deposition is can include atomic layer deposition, chemical vapor deposition, MOCVD, molecular beam epitaxy, evaporation, sputtering, or pulsed-laser deposition.
摘要:
A method of making nanowire probes is provided. The method includes providing a template having a nanoporous structure, providing a probe tip that is disposed on top of the template, and growing nanowires on the probe tip, where the nanowires are grown from the probe tip along the nanopores, and the nanowires conform to the shape of the nanopores.
摘要:
A localized nanostructure growth apparatus that has a partitioned chamber is provided, where a first partition includes a scanning probe microscope (SPM) and a second partition includes an atomic layer deposition (ALD) chamber, where the first partition is hermetically isolated from the second partition, and at least one SPM probe tip of the SPM is disposed proximal to a sample in the ALD chamber. According to the invention, the hermetic isolation between the chambers prevents precursor vapor from damaging critical microscope components and ensuring that contaminants in the ALD chamber can be minimized.
摘要:
The current invention provides a method of fabricating quantum confinement (QC) in a solar cell that includes using atomic layer deposition (ALD) for providing at least one QC structure embedded into an intrinsic region of a p-i-n diode in the solar cell, where optical and electrical properties of the confinement structure are adjusted according to at least one dimension of the confinement structure. The QC structures can include quantum wells, quantum wires, quantum tubes, and quantum dots.
摘要:
Area selective atomic layer deposition is provided by a method including the following steps. First, a substrate is provided. Second, a tip of a scanning probe microscope (SPM) is disposed in proximity to the surface of the substrate. An electrical potential is then established between the tip and the surface that cause one or more localized electrical effects in proximity to the tip. Deposition reactants for atomic layer deposition (ALD) are provided, and deposition occurs in a pattern defined by the localized electrical effects because of locally enhanced ALD reaction rates.
摘要:
Efficient photovoltaic devices with quantum dots are provided. Quantum dots have numerous desirable properties that can be used in solar cells, including an easily selected bandgap and Fermi level. In particular, the size and composition of a quantum dot can determine its bandgap and Fermi level. By precise deposition of quantum dots in the active layer of a solar cell, bandgap gradients can be present for efficient sunlight absorption, exciton dissociation, and charge transport. Mismatching Fermi levels are also present between adjacent quantum dots, allowing for built-in electric fields to form and aid in charge transport and the prevention of exciton recombination.
摘要:
A localized nanostructure growth apparatus that has a partitioned chamber is provided, where a first partition includes a scanning probe microscope (SPM) and a second partition includes an atomic layer deposition (ALD) chamber, where the first partition is hermetically isolated from the second partition, and at least one SPM probe tip of the SPM is disposed proximal to a sample in the ALD chamber. According to the invention, the hermetic isolation between the chambers prevents precursor vapor from damaging critical microscope components and ensuring that contaminants in the ALD chamber can be minimized.
摘要:
Efficient photovoltaic devices with quantum dots are provided. Quantum dots have numerous desirable properties that can be used in solar cells, including an easily selected bandgap and Fermi level. In particular, the size and composition of a quantum dot can determine its bandgap and Fermi level. By precise deposition of quantum dots in the active layer of a solar cell, bandgap gradients can be present for efficient sunlight absorption, exciton dissociation, and charge transport. Mismatching Fermi levels are also present between adjacent quantum dots, allowing for built-in electric fields to form and aid in charge transport and the prevention of exciton recombination.