DECOMPOSING DEVICE OF SEMICONDUCTOR THIN FILM

摘要

PURPOSE:To make it feasible to measure the impurity amount contained in a semiconductor substrate very precisely by a method wherein an oxide film is formed on a semiconductor substrate in a sealed container by means of irradiating with laser beams to be decomposed by the vapor of hydrofluoric acid with ultra high purity contained in said container for measuring impurity amount. CONSTITUTION:While a semiconductor substrate 3 is heated, a container 9 is filled with hydrofluoric acid 8 with ultra high purity and laser beams oscillated from an laser oscillator 14 is focussed by a focussing lens 6 and after reflected by a reflector 15 further transmitted through a window 2 to irradiate a semiconductor substrate. Next the gradient of reflector 15 is adjusted to scan the laser beams forming an oxide film in the specified region of semiconductor substrate 3. The oxide film is decomposed by the vapor of hydrofluoric acid 8 and the decomposed solution drips along the surface of substrate 3 to be collected in a decomposed solution receiver 10. The decomposed solution so far produced may be fed to a frameless atomic spectroscopic analyzer to analyze the amount of impurity.