Czochralski silicon single crystal doped with gallium and germanium

Abstract

The invention discloses a czochralski silicon single crystal doped with gallium and germanium, which contains the gallium with the concentration of 1*10-1*10 / cm and the germanium with the concentration of 1*10-1*10 / cm. The method comprises the following steps: restraining the formation of grown-in microdefect in a silicon single crystal through the germanium on the basis of avoiding light attenuation by utilizing the gallium as an electrical activity doping agent; obtaining the silicon single crystal in which the service life of a minority carrier is doubled compared with that of the silicon single crystal doped with the gallium independently, wherein the service life of the minority carrier is up to 100 Mus, and the minority carrier can be used for preparing an efficient solar battery. Meanwhile, the mechanical strength of the minority carrier is above 20 percent higher than that of the silicon single crystal doped with the gallium independently, and the mechanical breaking strength at the room temperature is up to 300 N / mm; and when the minority carrier is used in the solar battery, a silicon chip can be thinned, thereby reducing the manufacturing cost of the solar battery.

Description

technical field [0001] The invention belongs to the field of semiconductor silicon materials, in particular to Czochralski silicon single crystals co-doped with gallium and germanium for solar cells. Background technique [0002] Solar energy is an inexhaustible clean energy. Using the photoelectric conversion characteristics of semiconductor materials, it can be prepared into solar cells, which can convert solar energy into electrical energy. [0003] Czochralski silicon single crystal is one of the main materials for producing solar cells. In traditional solar technology, boron-doped Czochralski silicon single crystal is widely used in the preparation of solar cells. However, due to the substitutional boron atoms in the boron-doped Czochralski silicon single crystal and the interstitial oxygen atoms in the single crystal silicon will form a boron-oxygen complex under light or carrier injection, and the boron-oxygen complex is a deep energy The level recombination center ...

AI Technical Summary

Problems solved by technology

However, due to the disadvantages of the current Gallium-doped Czochralski silicon single crystal itself with low mechanical strength, if the thickness of the silicon wafer is reduced, the silicon wafer will be easily damaged and broken during the process of processing, battery preparation, and battery assembly into components. The increase in the breakage rate of silicon wafers will inevitably lead to an increase in cost