A bipolar solar cell includes a backside junction formed by an N-type silicon substrate and a P-type polysilicon emitter formed on the backside of the solar cell. An antireflection layer may be formed on a textured front surface of the silicon substrate. A negative polarity metal contact on the front side of the solar cell makes an electrical connection to the substrate, while a positive polarity metal contact on the backside of the solar cell makes an electrical connection to the polysilicon emitter. An external electrical circuit may be connected to the negative and positive metal contacts to be powered by the solar cell. The positive polarity metal contact may form an infrared reflecting layer with an underlying dielectric layer for increased solar radiation collection.

A solar cell is provided with: a semiconductor substrate having a light-receiving surface and a non-light-receiving surface; a PN junction section formed on the semiconductor substrate; a passivation layer formed on the light-receiving surface and/or the non-light-receiving surface; and power extraction electrodes formed on the light-receiving surface and the non-light-receiving surface. The solar cell is characterized in that the passivation layer includes an aluminum oxide film having a thickness of 40 nm or less. As a result of forming a aluminum oxide film having a predetermined thickness on the surface of the substrate, it is possible to achieve excellent passivation performance and excellent electrical contact between silicon and the electrode by merely firing the conductive paste, which is conventional technology. Furthermore, an annealing step, which has been necessary to achieve the passivation effects of the aluminum oxide film in the past, can be eliminated, thus dramatically reducing costs.

A solar cell is provided, including a substrate having a rear surface including P-type regions and N-type regions, first dielectric layers each formed over a N-type region, first doped polysilicon layers each formed on a first dielectric layer and doped with an N-type doping element, second dielectric layers each formed over a P-type region, second doped polysilicon layers each formed on a second dielectric layer and doped with a P-type doping element, a passivation layer formed over surfaces of the first and second doped polysilicon layers, and first and second electrodes penetrating the passivation layer. Each first electrode is electrically connected to a first doped polysilicon layer and each second electrode is electrically connected to a second doped polysilicon layer. A first roughness of a surface of a first doped polysilicon layer is greater than a second roughness of a surface of a second doped polysilicon layer.

A solar cell structure comprises a substrate including a front side and a back side. A first tunnel oxide layer, a first polycrystalline silicon layer, a first silicon nitride layer, and a plurality of first electrodes are sequentially formed on the front side of the substrate. A second tunnel oxide layer, a second polycrystalline silicon layer, a second silicon nitride layer, and a plurality of second electrodes are sequentially formed on the back side of the substrate.

A solar cell module with interconnect wires wire-bonded to back-contact solar cells. A solar cell module using an interconnect board to electrical interconnect back-contact solar cells. The interconnect board may also contain a bypass diode and circuitry to connect the bypass diode to solar cells of the module.

An ion implantation system having a grid assembly. The system includes a plasma source configured to provide plasma in a plasma region; a first grid plate having a plurality of apertures configured to allow ions from the plasma region to pass therethrough, wherein the first grid plate is configured to be biased by a power supply; a second grid plate having a plurality of apertures configured to allow the ions to pass therethrough subsequent to the ions passing through the first grid plate, wherein the second grid plate is configured to be biased by a power supply; and a substrate holder configured to support a substrate in a position where the substrate is implanted with the ions subsequent to the ions passing through the second grid plate.

A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. A trench structure separates the P-type doped region from the N-type doped region. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. The trench structure may include a textured surface for increased solar radiation collection. Among other advantages, the resulting structure increases efficiency by providing isolation between adjacent P-type and N-type doped regions, thereby preventing recombination in a space charge region where the doped regions would have touched.

A solar cell capable of preventing short-circuiting during signaling connection and a method for manufacturing the solar cell. A solar cell includes a semiconductor substrate, a first semiconductor layer having a conductivity type different from that of the semiconductor substrate. The first semiconductor layer includes a main functional portion which has a first base end portion on one side in a first direction of the semiconductor substrate over an entire length in a second direction and a plurality of first collecting portions extending from the first base end portion toward the other side in the first direction and on which a first electrode pattern is stacked, and an isolation portion which is formed linearly at an end portion on the other side in the first direction of the semiconductor substrate over an entire length in the second direction and on which the first electrode pattern is not stacked.

A solar cell capable of preventing short-circuiting during signaling connection and a method for manufacturing the solar cell. A solar cell includes a semiconductor substrate, a first semiconductor layer having a conductivity type different from that of the semiconductor substrate. The first semiconductor layer includes a main functional portion which has a first base end portion on one side in a first direction of the semiconductor substrate over an entire length in a second direction and a plurality of first collecting portions extending from the first base end portion toward the other side in the first direction and on which a first electrode pattern is stacked, and an isolation portion which is formed linearly at an end portion on the other side in the first direction of the semiconductor substrate over an entire length in the second direction and on which the first electrode pattern is not stacked.

In various embodiments, photovoltaic devices incorporate discontinuous passivation layers (i) disposed between a thin-film absorber layer and a partner layer, (ii) disposed between the partner layer and a front contact layer, and/or (iii) disposed between a back contact layer and the thin-film absorber layer.