Abstract: Photoelectrochemical (PEC) technology for the conversion of solar energy into chemicals may require cost-effective photoelectrodes to efficiently and stably drive anodic and/or cathodic half-reactions to complete the overall reactions for storing solar energy in chemical bonds. Apparatus and systems incorporating effectively transparent metal catalysts enable the design and/or implementation of PEC devices for light harvesting. Triple-junction photocathodes with the triangular catalyst grids are provided to improve the efficiency of the photocathodes to generate renewable fuel from sunlight.

Abstract: An image sensor is fabricated by first heavily p-type doping the thin top monocrystalline silicon substrate of an SOI wafer, then forming a relatively lightly p-doped epitaxial layer on a top surface of the top silicon substrate, where p-type doping levels during these two processes are controlled to produce a p-type dopant concentration gradient in the top silicon substrate. Sensing (circuit) elements and associated metal interconnects are fabricated on the epitaxial layer, then the handling substrate and oxide layer of the SOI wafer are at least partially removed to expose a lower surface of either the top silicon substrate or the epitaxial layer, and then a pure boron layer is formed on the exposed lower surface. The p-type dopant concentration gradient monotonically decreases from a maximum level near the top-silicon/epitaxial-layer interface to a minimum concentration level at the epitaxial layer's upper surface.

Abstract: An image sensor is fabricated by first heavily p-type doping the thin top monocrystalline silicon substrate of an SOI wafer, then forming a relatively lightly p-doped epitaxial layer on a top surface of the top silicon substrate, where p-type doping levels during these two processes are controlled to produce a p-type dopant concentration gradient in the top silicon substrate. Sensing (circuit) elements and associated metal interconnects are fabricated on the epitaxial layer, then the handling substrate and oxide layer of the SOI wafer are at least partially removed to expose a lower surface of either the top silicon substrate or the epitaxial layer, and then a pure boron layer is formed on the exposed lower surface. The p-type dopant concentration gradient monotonically decreases from a maximum level near the top-silicon/epitaxial-layer interface to a minimum concentration level at the epitaxial layer's upper surface.

Abstract: Back-illuminated DUV/VUV/EUV radiation or charged particle image sensors are fabricated using a method that utilizes a plasma atomic layer deposition (plasma ALD) process to generate a thin pinhole-free pure boron layer over active sensor areas. Circuit elements are formed on a semiconductor membrane's frontside surface, and then an optional preliminary hydrogen plasma cleaning process is performed on the membrane's backside surface. The plasma ALD process includes performing multiple plasma ALD cycles, with each cycle including forming an adsorbed boron precursor layer during a first cycle phase, and then generating a hydrogen plasma to convert the precursor layer into an associated boron nanolayer during a second cycle phase. Gasses are purged from the plasma ALD process chamber after each cycle phase. The plasma ALD cycles are repeated until the resulting stack of boron nanolayers has a cumulative stack height (thickness) that is equal to a selected target thickness.

Abstract: An image sensor is fabricated by first heavily p-type doping the thin top monocrystalline silicon substrate of an SOI wafer, then forming a relatively lightly p-doped epitaxial layer on a top surface of the top silicon substrate, where p-type doping levels during these two processes are controlled to produce a p-type dopant concentration gradient in the top silicon substrate. Sensing (circuit) elements and associated metal interconnects are fabricated on the epitaxial layer, then the handling substrate and oxide layer of the SOI wafer are at least partially removed to expose a lower surface of either the top silicon substrate or the epitaxial layer, and then a pure boron layer is formed on the exposed lower surface. The p-type dopant concentration gradient monotonically decreases from a maximum level near the top-silicon/epitaxial-layer interface to a minimum concentration level at the epitaxial layer's upper surface.

Abstract: An image sensor utilizes a pure boron layer and a second epitaxial layer having a p-type dopant concentration gradient to enhance sensing DUV, VUV or EUV radiation. Sensing (circuit) elements and associated metal interconnects are fabricated on an upper surface of a first epitaxial layer, then the second epitaxial layer is formed on a lower surface of the first epitaxial layer, and then a pure boron layer is formed on the second epitaxial layer. The p-type dopant concentration gradient is generated by systematically increasing a concentration of p-type dopant in the gas used during deposition/growth of the second epitaxial layer such that a lowest p-type dopant concentration of the second epitaxial layer occurs immediately adjacent to the interface with the first epitaxial layer, and such that a highest p-type dopant concentration of the second epitaxial layer occurs immediately adjacent to the interface with pure boron layer.

Abstract: An image sensor for short-wavelength light includes a semiconductor membrane, circuit elements formed on a first surface of the semiconductor membrane, and a boron-coated, textured surface on a second surface of the semiconductor membrane. The textured surface comprises pseudo-random, periodic, and/or random distribution of upright pyramids, inverted pyramids, and/or nanocones. The textured surface reduces the reflection of incident light across wide bands in the DUV and VUV regimes, thus increasing the amount of light absorbed and improving the efficiency of the image sensor. Reflectance may be further reduced by applying an antireflective coating on the textured surface. The image sensor may be a two-dimensional area sensor, or a one-dimensional array sensor. and incorporated in an inspection system.

Abstract: Photoelectrochemical (PEC) technology for the conversion of solar energy into chemicals may require cost-effective photoelectrodes to efficiently and stably drive anodic and/or cathodic half-reactions to complete the overall reactions for storing solar energy in chemical bonds. Apparatus and systems incorporating effectively transparent metal catalysts enable the design and/or implementation of PEC devices for light harvesting. Triple-junction photocathodes with the triangular catalyst grids are provided to improve the efficiency of the photocathodes to generate renewable fuel from sunlight.

Abstract: In conventional solar cells with metal contacts, a non-negligible fraction of the incoming solar power is immediately lost either through absorption or reflection upon interaction with the contacts. Effectively transparent contacts (“ETCs”) for solar cells can be referred to as three-dimensional contacts designed to redirect incoming light onto a photoabsorbing surface of a solar cell. In many embodiments, the ETCs have triangular cross-sections. Such ETCs can be placed on a photoabsorbing surface such that at least one of their sides forms an angle with the photoabsorbing surface. In this configuration, the ETCs can redirect incident light onto the photoabsorbing surface, mitigating or eliminating reflection loss compared to conventional solar cells. When constructed in accordance with a number of embodiments of the invention, ETCs can be effectively transparent and highly conductive.

Abstract: An image sensor utilizes a pure boron layer and a second epitaxial layer having a p-type dopant concentration gradient to enhance sensing DUV, VUV or EUV radiation. Sensing (circuit) elements and associated metal interconnects are fabricated on an upper surface of a first epitaxial layer, then the second epitaxial layer is formed on a lower surface of the first epitaxial layer, and then a pure boron layer is formed on the second epitaxial layer. The p-type dopant concentration gradient is generated by systematically increasing a concentration of p-type dopant in the gas used during deposition/growth of the second epitaxial layer such that a lowest p-type dopant concentration of the second epitaxial layer occurs immediately adjacent to the interface with the first epitaxial layer, and such that a highest p-type dopant concentration of the second epitaxial layer occurs immediately adjacent to the interface with pure boron layer.

Abstract: In conventional solar cells with metal contacts, a non-negligible fraction of the incoming solar power is immediately lost either through absorption or reflection upon interaction with the contacts. Effectively transparent contacts (“ETCs”) for solar cells can be referred to as three-dimensional contacts designed to redirect incoming light onto a photoabsorbing surface of a solar cell. In many embodiments, the ETCs have triangular cross-sections. Such ETCs can be placed on a photoabsorbing surface such that at least one of their sides forms an angle with the photoabsorbing surface. In this configuration, the ETCs can redirect incident light onto the photoabsorbing surface, mitigating or eliminating reflection loss compared to conventional solar cells. When constructed in accordance with a number of embodiments of the invention, ETCs can be effectively transparent and highly conductive.

Abstract: Increasing the power conversion efficiency of silicon (Si) photovoltaics is a key enabler for continued reductions in the cost of solar electricity. Disclosed herein is a multi-junction photovoltaic cell that does not utilize a conventional interconnection layer and instead places a wide bandgap oxide conductor, for example, a metal oxide such as TiO2, between a top light absorption layer having a relatively large bandgap and a bottom light absorption layer having a relatively small bandgap. The advantageous omission of a conventional interconnection layer between the two subcells is enabled by low contact resistivity between the top and bottom light absorbing layers provided by the wide bandgap oxide conductor. The absence of the conventional interconnect between the subcells significantly reduces both optical losses and processing steps. The disclosed photovoltaic cell may thus enable low-cost, high-efficiency multi-junction devices through less complex manufacturing processes and lower material costs.

Abstract: Superstrates containing ETCs in accordance with various embodiments of the invention can be implemented to reduce optical losses by decreasing the thickness of the TCO and by reducing or eliminating shading losses of metal grid fingers. ETC superstrates can include a transparent material with grooves, which can be infilled with reflective, conductive material(s) such as but not limited to silver and aluminum. In further embodiments, the grooves are triangular-shaped. ETC superstrates can enable a significant reduction in the TCO thickness required for current extraction with a high fill factor. By reducing the thickness of the TCO layer in solar cells, the short circuit current density can be enhanced by more than 1 mA/cm2 due to decreased parasitic absorption and optimized antireflection properties.

Abstract: In conventional solar cells with metal contacts, a non-negligible fraction of the incoming solar power is immediately lost either through absorption or reflection upon interaction with the contacts. Effectively transparent contacts (“ETCs”) for solar cells can be referred to as three-dimensional contacts designed to redirect incoming light onto a photoabsorbing surface of a solar cell. In many embodiments, the ETCs have triangular cross-sections. Such ETCs can be placed on a photoabsorbing surface such that at least one of their sides forms an angle with the photoabsorbing surface. In this configuration, the ETCs can redirect incident light onto the photoabsorbing surface, mitigating or eliminating reflection loss compared to conventional solar cells. When constructed in accordance with a number of embodiments of the invention, ETCs can be effectively transparent and highly conductive.

Abstract: Solar cells in accordance with a number of embodiments of the invention incorporate effectively transparent 3D contacts that redirect light incident on the contacts onto the photoabsorbing surfaces of the solar cells. One embodiment includes a photoabsorbing surface and a plurality of three-dimensional contacts formed on the photoabsorbing surface. The plurality of three-dimensional contacts are spaced apart so that radiation is incident on a portion of the photoabsorbing surface. In addition, the three-dimensional contacts include at least one surface that redirects radiation incident on the three-dimensional contacts onto the photoabsorbing surface.