Solar cell epitaxial wafer and manufacturing method thereof

Abstract

The invention relates to a solar cell epitaxial wafer and a manufacturing method thereof. The solar cell epitaxial wafer comprises a substrate, a buffer layer, a sacrificial layer and a solar cell layer which are sequentially arranged, wherein the sacrificial layer comprises a first sacrificial layer and a second sacrificial layer, the first sacrificial layer is arranged close to the buffer layer, the second sacrificial layer is arranged close to the first sacrificial layer, the corrosion rate of the first sacrificial layer is greater than the corrosion rate of the second sacrificial layer, a plurality of mutually parallel bar-shaped grooves are distributed on the first sacrificial layer, and the second sacrificial layer is provided with a plurality of bar-shaped bulges which are tightly matched with the bar-shaped grooves. A technical problem that the sacrificial layer is corroded by a corrosive liquid with an unpredictable direction and different speeds is solved. The time of a stripping process can be reduced, and damages of the substrates and the solar cell layer in the stripping process can also be reduced, thereby improving the quality of a solar cell product and the yield of a production line.

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

This situation will lead to: 1. The acid solution corrodes faster in some areas (the acid solution goes deep into the interior along the irregular channel), while the corrosion is slower in some areas

The gas generated in the rapidly corroded area is easy to accumulate between the substrate and the GaAs battery layer and is not easy to discharge, which hinders the further corrosion of the sacrificial layer by the acidic solution or hinders the supplement of the acidic solution to the front of the corrosion chemical reaction; 2. The gas cannot be discharged in time, and it is easy to cause the oxygen contained in the gas to react with the GaAs battery layer or substrate, resulting in damage to the battery layer (the reaction between oxygen and GaAs will cause GaAs to be more easily corroded by acid solution) or substrate defects that are not easy to repair (It has an impact on the secondary utilization of the substrate); 3. Gas accumulation will generate a certain pressure inside, and in severe cases, it will damage the GaAs battery layer or substrate

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