Solar cell epitaxial wafer and its manufacturing method

Abstract

The invention provides a solar cell epitaxial wafer and a manufacturing method thereof. The solar cell epitaxial wafer comprises a substrate, a buffer layer, sacrificial layers and a solar cell layer, wherein the substrate, the buffer layer, the sacrificial layers and the solar cell layer are sequentially disposed. The sacrificial layers comprise a first sacrificial layer and a second sacrificial layer. The first sacrificial layer is arranged to cling to the buffer layer. The second sacrificial layer is arranged to cling to the first sacrificial layer. The first sacrificial layer is provided with a plurality of grooves. The second sacrificial layer is provided with a plurality of projections matched with the grooves. The projections are internally provided with gaps that extend along the length direction of the grooves. By means of the plurality of gaps in the sacrificial layers, when the solar cell epitaxial wafer is immersed in a selective etching solution, the selective etching solution can enter the interior of the solar cell epitaxial wafer through the edges of the sacrificial layers via the above gaps. In this way, the etching speeds of the sacrificial layers are accelerated. Therefore, the duration of the epitaxy lift-off step during the manufacturing process of solar cells is reduced.

Description

technical field [0001] The invention relates to the technical field of solar cells. Specifically, it relates to a solar cell epitaxial wafer and a manufacturing method thereof. Background technique [0002] GaAs solar cell technology is developing rapidly, and its application fields have gradually expanded from space applications to ground applications. It has broad market prospects in the fields of portable energy and consumer electronics. Using epitaxial lift-off technology (ELO technology) to make GaAs solar cells, on the one hand, the GaAs substrate can be reused after peeling off, which can significantly reduce product costs; on the other hand, flexible GaAs solar cells can be made, and the efficiency is not only improved compared to before stripping , and the product is lighter and flexible, which is more conducive to aerospace and portable applications, etc., and has a wide range of uses. [0003] In the prior art, the process of making GaAs solar cells using epitax...

AI Technical Summary

Problems solved by technology

In actual stripping, the gas generated by the corrosion reaction is easy to accumulate between the substrate and the GaAs cell layer, which hinders the acidic solution from replenishing to the reaction front and further reduces the stripping speed.

Images