| 摘要 |
An improved photovoltaic cell and a method for making such cells is provided. In a generic sense, the preferred method comprises the step of (1) applying a coating of an aluminum metal paste onto the rear surface of the substrate in a suitable rear contact pattern, (2) applying a layer of a glass frit paste so as to envelop the rear contact, and (3) firing those pastes so as to form a rear contact protected by a glass overcoating. A front contact also is formed by applying a silver metal/glass frit paste onto the anti-reflection coating in a related front contact pattern. The front and rear contacts may be fired simultaneously or in two different steps. However, a single firing method is preferred because thicker aluminum contacts are possible. In a preferred embodiment, the cell provided by the invention includes (1) a silicon substrate having a shallow p-n junction adjacent its front surface, (2) a plurality of silver soldering pads bonded to the rear surface of the substrate, (3) an aluminum contact on the rear surface of the substrate having openings that expose at least portions of said silver pads, (4) a silver contact surrounded by an anti-reflection coating on the front surface of the substrate, and (5) a glass layer overlying the aluminum contact so as to protect it against oxidation and corrosion. The glass layer has windows exposing portions of the soldering pads for solder attachment of connecting wire ribbons.
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