In certain examples, methods and photo-responsive structures are directed to devices involving a diamond-based photoconductive switch having a doped diamond-grown material in the switch. The doped diamond-grown material may be formed from different gases combined on a diamond seed, such that as grown, the diamond-based material manifests a controlled dopant concentration level of a polarity type and over a depth of optical absorption sufficient to ionize the dopants in response to an optical signal.

A method for manufacturing a solar cell having a P-type silicon substrate wherein one main surface is a light-receiving surface and another is a backside, a plurality of back surface electrodes formed on a part of the backside, an N-type layer in at least a part of the light-receiving surface, and contact areas in which the substrate contacts the electrodes; wherein the P-type silicon substrate is a silicon substrate doped with gallium and has a resistivity of 2.5 Ω.Math.cm or less; and a back surface electrode pitch P.sub.rm [mm] of contact areas in which the P-type silicon substrate is in contact with the back surface electrodes and the resistivity R.sub.sub [Ω.Math.cm] of the substrate satisfy the relation represented by the following formula (1).
log(R.sub.sub)≤−log(P.sub.rm)+1.0  (1)

A method for manufacturing a solar cell having a P-type silicon substrate wherein one main surface is a light-receiving surface and another is a backside, a plurality of back surface electrodes formed on a part of the backside, an N-type layer in at least a part of the light-receiving surface, and contact areas in which the substrate contacts the electrodes; wherein the P-type silicon substrate is a silicon substrate doped with gallium and has a resistivity of 2.5 Ω.Math.cm or less; and a back surface electrode pitch P.sub.rm [mm] of contact areas in which the P-type silicon substrate is in contact with the back surface electrodes and the resistivity R.sub.sub [Ω.Math.cm] of the substrate satisfy the relation represented by the following formula (1).
log(R.sub.sub)≤−log(P.sub.rm)+1.0  (1)

A meta optical device configured to sense incident light includes a plurality of nanorods each having a shape dimension less than a wavelength of the incident light. Each nanorod includes a first conductivity type semiconductor layer, an intrinsic semiconductor layer, and a second conductivity type semiconductor layer. The meta optical device may separate and sense wavelengths of the incident light.

A meta optical device configured to sense incident light includes a plurality of nanorods each having a shape dimension less than a wavelength of the incident light. Each nanorod includes a first conductivity type semiconductor layer, an intrinsic semiconductor layer, and a second conductivity type semiconductor layer. The meta optical device may separate and sense wavelengths of the incident light.

Provided is a solar cell and a method for manufacturing the same, the method includes: forming a doped layer on a surface of a semiconductor substrate, the doped layer having a first doping concentration of a doping element in the doped layer; depositing, on a surface of the doped layer, a doped amorphous silicon layer including the doping element; selectively removing at least one region of the doped amorphous silicon layer; performing annealing treatment, for the semiconductor substrate to form a lightly doped region having the first doping concentration and a heavily doped region having a second doping concentration in the doped layer, the second doping concentration is greater than the first doping concentration; and forming a solar cell by post-processing the annealed semiconductor substrate. The solar cell and the method for manufacturing the same simplify the manufacturing process and improve conversion efficiency of the solar cell.

Provided is a method for preparing a gallium- and nitrogen-doped monocrystalline silicon using a Czochralski process, including: introducing a doping gas at least including a first amount of nitrogen into a molten mixture in a single crystal furnance; withdrawing a seed from the molten mixture while introducing the doping gas including a second amount of nitrogen into the molten mixture, a second ratio of the second amount of nitrogen to the doping gas being smaller than the first ratio; and upon occurrence of a shoulder of the monocrystalline silicon rod, adjusting the second amount of nitrogen to a third amount in such a manner that a third ratio of the third amount of nitrogen to the doping gas is greater than the second ratio, to form a monocrystalline silicon rod. A solar cell and a photovoltaic module including a gallium- and nitrogen-doped silicon wafer prepared therefrom are also provided.

Provided is a method for preparing a gallium- and nitrogen-doped monocrystalline silicon using a Czochralski process, including: introducing a doping gas at least including a first amount of nitrogen into a molten mixture in a single crystal furnance; withdrawing a seed from the molten mixture while introducing the doping gas including a second amount of nitrogen into the molten mixture, a second ratio of the second amount of nitrogen to the doping gas being smaller than the first ratio; and upon occurrence of a shoulder of the monocrystalline silicon rod, adjusting the second amount of nitrogen to a third amount in such a manner that a third ratio of the third amount of nitrogen to the doping gas is greater than the second ratio, to form a monocrystalline silicon rod. A solar cell and a photovoltaic module including a gallium- and nitrogen-doped silicon wafer prepared therefrom are also provided.

Various embodiments of a monolithic avalanche photodiode (APD) are described, which may be fabricated on a silicon-on-insulator substrate. The monolithic APD includes an optical waveguide that guides an incident light to an active region of the APD. An optical coupler is integrally formed with the optical waveguide to capture the incident light. The monolithic APD also includes an optical reflector to reflect a portion of the incident light that is not readily captured by the optical coupler back to the optical coupler for further capturing. The active region includes an absorption layer for converting the incident light into a photocurrent, an epitaxial structure for amplifying the photocurrent by avalanche multiplication, as well as a pair of electrical conductors for conducting the amplified photocurrent.

Various embodiments of a monolithic avalanche photodiode (APD) are described, which may be fabricated on a silicon-on-insulator substrate. The monolithic APD includes an optical waveguide that guides an incident light to an active region of the APD. An optical coupler is integrally formed with the optical waveguide to capture the incident light. The monolithic APD also includes an optical reflector to reflect a portion of the incident light that is not readily captured by the optical coupler back to the optical coupler for further capturing. The active region includes an absorption layer for converting the incident light into a photocurrent, an epitaxial structure for amplifying the photocurrent by avalanche multiplication, as well as a pair of electrical conductors for conducting the amplified photocurrent.