Photovoltaic Cell and Production Thereof

Abstract

An efficient photovoltaic cell, and its process of manufacture, is disclosed wherein the back surface p-n junction is removed from a doped substrate having an oppositely doped emitter layer. A front surface and edges and optionally the back surface periphery are masked and a back surface etch is performed. The mask is not removed and acts as an anti-reflective coating, a passivating agent, or both. The photovoltaic cell retains an untextured back surface whether or not the front is textured and the dopant layer on the back surface is removed to enhance the cell efficiency. Optionally, a back surface field is formed.

Description

BACKGROUND OF THE INVENTION[0001]This invention relates to photovoltaic devices, particularly photovoltaic devices comprising thin layers of semiconductor materials, such as thin layers of monocrystalline or multicrystalline silicon. More particularly, this invention relates to photovoltaic devices comprising monocrystalline or multicrystalline silicon semiconductor materials. These devices which comprise doped wafers of monocrystalline or multicrystalline silicon convert light energy into electrical energy.[0002]These photovoltaic devices, also known as photovoltaic cells, are used to convert light energy into electrical energy. Photovoltaic cells can be used to generate energy (solar cells) or they can be used as photodector elements in other devices. Photovoltaic cells are a source of renewable energy. However their use is limited by their electrical output. Typically, many photovoltaic cells are arranged in one or more panels or modules in order to generate sufficient power requ...

AI Technical Summary

Benefits of technology

This process reduces cell damage, enables the use of thinner wafers, and increases the front surface area, leading to higher energy conversion efficiency and lower production costs while maintaining the effectiveness of the back surface field.

Problems solved by technology

However their use is limited by their electrical output.

However, such masking requires additional time, materials, and handling, particularly if it must be removed later.

The physical stacking of the wafers can cause some wafers to be damaged.

Unfortunately, the coin stacking method significantly limits the thinness of the wafers.

As a result, coin stacking limits the cost savings achievable through use of thinner wafers.

Another disadvantage of the coin stacking method is that it decreases the area of the front surface of a photovoltaic cell.

Photovoltaic cells with thin substrates have many benefits, including reduced material requirements, lower cost and less weight, but also exhibit a decrease in efficiency, generally attributed to an increase in the diffusion of minority charge carriers to the back surface of the cell.

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