Other

Electric Power Research Institute Incorporated

Sunpower Corporation

Pierre J Verlinden

Haruo Nakamura

Norio Komura

Yasuo Sugimoto

Akira Terao

Junichi Ohmura

Richard M Swanson

William P Mulligan

Ronald A Sinton

A method of fabricating a back surface point contact silicon solar cell having p-doped regions and n-doped regions on the same side by forming a passivating layer on a surface of the cell having opened windows at the p-doped regions and the n-doped regions, by depositing and patterning a first metal layer comprising aluminum on the passivating layer in such a way that the first metal layer comes into contact with the p-doped regions and the n-doped regions, by depositing an insulator layer of inorganic material on the first metal layer, by etching and patterning the insulator layer in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, and by depositing a second three-layer metal stack comprising materials other than aluminum, on the insulator layer of polyimide in such a way that the second three-layer metal stack comes into contact with the one of the p-doped regions and the n-doped regions. With this, the cell surface to be soldered onto a metallized substrate is well planarized and even to ensure sufficient conductibility, with less voids and less solder fatigue.

Method of fabricating a silicon solar cell

A method of fabricating a back surface point contact silicon solar cell having p-doped regions and n-doped regions on the same side by forming a passivating layer on a surface of the cell having opened windows at the p-doped regions and the n-doped regions, by depositing and patterning a first metal layer on the passivating layer in such a way that the first metal layer comes into contact with the p-doped regions and the n-doped regions, by depositing an insulator layer of polyimide on the first metal layer, by etching and patterning the insulator layer of polyimide in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, by curing the insulator layer of polyimide by heating at temperature for a period, by additionally curing the insulator layer of polyimide by heating at a second temperature, which is higher than the first temperature, and by depositing a second metal layer made of metal stack on the insulator layer of polyimide in such a way that the second metal layer comes into contact with the one of the p-doped regions and the n-doped regions. With this, the cell surface to be soldered onto a metallized substrate is well planarized and even to ensure sufficient conductibility, with less voids and less solder fatigue.

A method of fabricating a back surface point contact silicon solar cell having p-doped regions and n-doped regions on the same side by forming a passivating layer on a surface of the cell having opened windows at the p-doped regions and the n-doped regions, b depositing and patterning a first metal layer on the passivating layer in such a way that the first metal layer comes into contact with the p-doped regions and the n-doped regions, by depositing a first insulator layer of polyimide on the first metal layer, by etching and patterning the first insulator layer of polyimide in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, by depositing a second insulator layer of polyimide on the first insulator layer of polyimide, by etching and patterning the second insulator layer of polyimide in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, by curing the first insulator layer of polyimide by heating at a predetermined second temperature for a predetermined second time, and by depositing a second metal layer on the second insulator layer of polyimide in such a way that the second metal layer comes into contact with the one of the p-doped regions and the n-doped regions. With this, the cell surface to be soldered onto a metallized substrate is well planarized and even to ensure sufficient conductibility, with less voids and less solder fatigue.

Edge passivation for a small area silicon cell is provided in a batch process by providing streets between individual cells formed in a silicon substrate and diffusing dopant through the substrate along the streets. Following completion of fabrication of the plurality of cells in the substrate, the substrate is sawed along the streets with the diffused region providing passivation along the edges of the individual die.

Edge passivated silicon solar/photo cell and method of manufacture

A method of fabricating a back surface point contact silicon solar cell having p-doped regions and n-doped regions on the same side by forming a passivating layer on a surface of the cell having opened windows at the p-doped regions and the n-doped regions, by depositing and patterning a first metal layer on the passivating layer in such a way that the first metal layer comes into contact with the p-doped regions and the n-doped regions, by depositing a first insulator layer of inorganic material on the first metal layer, by etching and patterning the first insulator layer in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, by depositing a second insulator layer of organic material on the first insulator layer, by etching and patterning the second insulator layer in such a way that the insulator layer has opened windows at the one of the p-doped regions and the n-doped regions, by curing the second insulator layer by heating at a predetermined temperature for a predetermined time, and depositing a second metal layer on the second insulator layer of organic material in such a way that the second metal layer comes into contact with the one of the p-doped regions and the n-doped regions. With this, the cell surface to be soldered onto a metallized substrate is well planarized and even to ensure sufficient conductibility, with less voids and less solder fatigue.

A silicon solar cell has increased efficiency by providing an anti-reflection and passivation layer comprising a layer of silicon dioxide thermally grown on a surface of a silicon body and a layer of titanium dioxide deposited on the layer of silicon oxide. In fabricating the composite anti-reflection passivation layer, a layer of aluminum is first deposited on a surface of the thermally grown silicon oxide. After annealing the aluminum layer, the aluminum is removed from the silicon dioxide layer, and the layer of titanium dioxide is then deposited on the surface of the silicon dioxide from which the aluminum was removed. A layer of magnesium fluoride can be deposited on the surface of the titanium dioxide.

Growing community of inventors

Palo Alto, CA, United States of America

Pierre J Verlinden