MEASURING APPARATUS FOR LINEWIDTH AND DEPTH OF FINE PATTERN BY USING OPTICAL FIBER AND MEASURING METHOD OF THE SAME

摘要

The present invention relates to an optical device and a surface pattern measuring apparatus. The invention comprises: a light source part flashing out coherent light in broadband; a first optical fiber coupler, which receives incident light from the light source part into its inlet part and separating a first incident light and a second incident light to a first output part and a second output part, respectively; a first terminal receiving the second incident light from the second output part of the first optical fiber coupler; a second terminal receiving the first incident light from the first terminal to the second terminal as a sample; an optical circulator including a third terminal, which receives a reflective light reflected from the sample and outputs it; a first input part, which receives the first incident light from the first output part of the first optical fiber coupler; a second input part receiving the reflective light; a second optical fiber coupler including an output part, which outputs the combined second incident light and the reflective light; and a spectrum analyzer, which receives the output light from the second optical fiber coupler and measures the strength of the interference light according to the wavelength.