A solar cell apparatus 100 and a method for forming said solar cell apparatus 100, comprising a substrate 101, a n-type transparent conductive oxide (TCO) layer 102 deposited atop said substrate 101, a p-i-n structure 200 that includes a p-type layer 103, an i-type layer 104, a n-type layer 105, a metal back layer 106 deposited atop said n-type layer 105 of the p-i-n structure 200. The n-type layer 105 comprises n-type donors 115 including phosphorus atoms. The n-type donors 115 include oxygen atoms at an atomic concentration comprised between 5% and 25% of the overall atomic composition of the n-type layer 105.

The present invention relates to a microcrystalline silicon thin film solar cell and the manufacturing method thereof, using which not only the crystallinity of a microcrystalline silicon thin film that is to be formed by the manufacturing method can be controlled and adjusted at will and the defects in the microcrystalline silicon thin film can be fixed, but also the device characteristic degradation due to chamber contamination happening in the manufacturing process, such as plasma enhanced chemical vapor deposition (PECVD), can be eliminated effectively.

The present invention relates to a microcrystalline silicon thin film solar cell and the manufacturing method thereof, using which not only the crystallinity of a microcrystalline silicon thin film that is to be formed by the manufacturing method can be controlled and adjusted at will and the defects in the microcrystalline silicon thin film can be fixed, but also the device characteristic degradation due to chamber contamination happening in the manufacturing process, such as plasma enhanced chemical vapor deposition (PECVD), can be eliminated effectively.

A photovoltaic device and method include forming a plurality of pillar structures in a substrate, forming a first electrode layer on the pillar structures and forming a continuous photovoltaic stack including an N-type layer, a P-type layer and an intrinsic layer on the first electrode. A second electrode layer is deposited over the photovoltaic stack such that gaps or fissures occur in the second electrode layer between the pillar structures. The second electrode layer is wet etched to open up the gaps or fissures and reduce the second electrode layer to form a three-dimensional electrode of substantially uniform thickness over the photovoltaic stack.

A photovoltaic device and method include forming a plurality of pillar structures in a substrate, forming a first electrode layer on the pillar structures and forming a continuous photovoltaic stack including an N-type layer, a P-type layer and an intrinsic layer on the first electrode. A second electrode layer is deposited over the photovoltaic stack such that gaps or fissures occur in the second electrode layer between the pillar structures. The second electrode layer is wet etched to open up the gaps or fissures and reduce the second electrode layer to form a three-dimensional electrode of substantially uniform thickness over the photovoltaic stack.

A solar cell can include a silicon substrate; a tunnel layer disposed on a first surface of the silicon substrate, the tunnel layer including a dielectric material; a polycrystalline silicon layer disposed on the tunnel layer; a dielectric layer disposed on the polycrystalline silicon layer; and an electrode penetrating through the dielectric layer and directly contacting with the polycrystalline silicon layer, wherein the polycrystalline silicon layer includes a metal crystal region positioned at a region where the polycrystalline silicon layer contacts the electrode, and wherein the metal crystal region includes a plurality of metal crystals, the plurality of metal crystals including a metal material same as a metal material included in the electrode.

A solar cell can include a silicon substrate; a tunnel layer disposed on a first surface of the silicon substrate, the tunnel layer including a dielectric material; a polycrystalline silicon layer disposed on the tunnel layer; a dielectric layer disposed on the polycrystalline silicon layer; and an electrode penetrating through the dielectric layer and directly contacting with the polycrystalline silicon layer, wherein the polycrystalline silicon layer includes a metal crystal region positioned at a region where the polycrystalline silicon layer contacts the electrode, and wherein the metal crystal region includes a plurality of metal crystals, the plurality of metal crystals including a metal material same as a metal material included in the electrode.

A photoelectric conversion device with improved electric characteristics is provided. The photoelectric conversion device has a structure in which a window layer is formed by a stack of a first silicon semiconductor layer and a second silicon semiconductor layer, and the second silicon semiconductor layer has high carrier concentration than the first silicon semiconductor layer and has an opening. Light irradiation is performed on the first silicon semiconductor layer through the opening without passing through the second silicon semiconductor layer; thus, light absorption loss in the window layer can be reduced.

A photoelectric conversion device with improved electric characteristics is provided. The photoelectric conversion device has a structure in which a window layer is formed by a stack of a first silicon semiconductor layer and a second silicon semiconductor layer, and the second silicon semiconductor layer has high carrier concentration than the first silicon semiconductor layer and has an opening. Light irradiation is performed on the first silicon semiconductor layer through the opening without passing through the second silicon semiconductor layer; thus, light absorption loss in the window layer can be reduced.

A germanium single-crystal wafer comprises silicon with an atomic concentration of from 3×10.sup.14 atoms/cc to 10×10.sup.13 atoms/cc, boron with an atomic concentration of from 1×10.sup.16 atoms/cc to 10×10.sup.18 atoms/cc, and gallium with an atomic concentration of from 1×10.sup.16 atoms/cc to 10×10.sup.19 atoms/cc. Further provided are a method for preparing the germanium single-crystal wafer, a method for preparing a germanium single-crystal ingot, and the use of the germanium single-crystal wafer for increasing the open-circuit voltage of a solar cell. The germanium single-crystal wafer has an improved electrical property in that it has a smaller difference in resistivity and carrier concentration.