Method for manufacturing solar cells having nano-micro composite structure on silicon substrate and solar cells manufactured thereby

Abstract

One embodiment of the present invention relates to a method for manufacturing solar cells having a nano-micro composite structure on a silicon substrate and solar cells manufactured thereby. The technical problem to be solved is to provide a method for manufacturing solar cells and solar cells manufactured thereby, the method being capable of forming micro wires in various sizes according to the lithographic design of a photoresist and forming nano wires, which have various sizes and aspect ratios, by adjusting the concentration of a wet etching solution and immersion time. To this end, the present invention provides a method for manufacturing solar cells and solar cells manufactured thereby, the method comprising the steps of: preparing a first conductive semiconductor substrate having a first surface and a second surface; patterning a photoresist on the second surface of the first conductive semiconductor substrate such that the plane form of the photoresist becomes a form in which multiple horizontal lines and multiple vertical lines intersect each other; electrolessly etching the semiconductor substrate so as to form a micro wire having a width of 1-3 μm and a height of 3-5 μm in a region corresponding to the photoresist and to form multiple nano wires having a width of 1-100 nm and a height of 1-3 μm in a region not corresponding to the photoresist; doping the micro wire and nano wires with a second conductive impurity by using POCl; forming a first electrode on the first surface of the semiconductor substrate; and forming a second electrode on the micro wire, wherein the efficiency of the solar cells is 10-13%, the efficiency being the ratio of output to incident light energy per unit area.