Systems and Methods of Laser Texturing and Crystallization of Material Surfaces

Abstract

The surface of a material is textured and crystallized in a single step by exposing the surface to pulses from an ultrafast laser. The laser treatment causes pillars to form on the treated surface. These pillars provide for greater light absorption. The crystallization of the material provides for higher electric conductivity and changes in optical properties of the material. The method may be performed in a gaseous environment, so that laser assisted chemical etching will aid in the texturing of the surface. This method may be used on various material surfaces, such as semiconductors, metals, ceramics, polymers, and glasses.

1 . (canceled) 
     
     
         2 . A method for micro texturing a surface of a thin film, comprising:
 providing a gaseous or vacuum environment in an area around the surface of the thin film;   irradiating a portion of the surface with short laser pulses;   moving at least one of the surface or a laser beam relative to each other to allow the short laser pulses to irradiate the surface;   wherein the method produces spikes on the thin film, resulting in changes in properties of the thin film;   wherein said thin film comprises a semiconductor material; and   wherein the laser pulses have a duration of between one femtosecond and one microsecond.   
     
     
         3 . The method of  claim 2 , wherein the laser pulses have a wavelength of between about 200 and about 1,600 nm. 
     
     
         4 . A system for micro texturing a surface of a thin film comprising:
 a chamber in an area around the surface of the thin film to provide a gaseous or vacuum environment;   an energy source providing a power supply for a radiation source, said radiation source for irradiating at least a portion of the surface;   wherein said thin film comprises a semiconductor material;   a base for retaining said thin film, said base or radiation source adapted to move relative to one another for irradiation wherein spikes are produced on the thin film, resulting in changes in properties of the thin film;   wherein said irradiation has a duration of between about one femtosecond and one microsecond; and   wherein said laser pulses have a wavelength of between about 400 and about 1,600 nanometers.   
     
     
         5 . The method of  claim 4 , wherein the laser pulses have a wavelength of between about 200 and about 1,600 nm. 
     
     
         6 . A surface of thin film, comprising a portion on which spikes are formed by irradiating the surface with short laser pulses in a vacuum or gaseous environment surrounding the surface, wherein the thin film comprises a semiconductor material; and wherein said irradiation has a duration of between one femtosecond and one microsecond. 
     
     
         7 . The surface of  claim 6 , wherein said irradiation has a wavelength of between about 200 and 1,600 nanometers. 
     
     
         8 . A method for micro texturing and crystallizing a surface of a thin film in a single step, comprising:
 providing a gaseous or vacuum environment in an area around the surface of the thin film;   irradiating a portion of the surface with short laser pulses;   moving at least one of the surface or a laser beam relative to each other to allow the short laser pulses to irradiate the surface;   wherein the method produces crystallization of and spikes on the thin film, resulting in changes in properties of the thin film;   wherein said thin film comprises a semiconductor material; and   wherein the laser pulses have a duration of between one femtosecond and one microsecond.   
     
     
         9 . A system for micro texturing and crystallizing a surface of a thin film in a single step comprising:
 a chamber in an area around the surface of the thin film to provide a gaseous or vacuum environment;   an energy source providing a power supply for a radiation source, said radiation source for irradiating at least a portion of the surface;   wherein said thin film comprises a semiconductor material;   a base for retaining said thin film, said base or radiation source adapted to move relative to one another for irradiation wherein crystallization is produced in and spikes are produced on the thin film, resulting in changes in properties of the thin film;   wherein said irradiation has a duration of between about one femtosecond and one microsecond; and   wherein said laser pulses have a wavelength of between about 400 and about 1,600 nanometers.   
     
     
         10 . A surface of thin film, comprising a portion on which spikes are formed and said thin film is crystallized by irradiating the surface with short laser pulses in a vacuum or gaseous environment surrounding the surface, wherein the thin film comprises a semiconductor material; and wherein said irradiation has a duration of between one femtosecond and one microsecond.