Patent ID: 6171975
Filing Date: 2001-01-09
Classification: H01L

Abstract:
A method of controlling the composition of a chemical treatment fluid to be used for the wet-chemical treatment of a semiconductor substrate by immersing the semiconductor substrate in a chemical treatment fluid containing ammonia and hydrogen peroxide to treat the surface of the substrate, said method comprising the steps of(a) measuring the composition and temperature of the chemical treatment fluid,(b) calculating the concentration of chemical species in the chemical treatment fluid using a chemical equilibrium analysis based on the measured values obtained in step (a),(c) calculating target wet-chemical treatment performance values by determining relationships between the chemical species concentration in the chemical treatment fluid, the treatment temperature and wet-chemical treatment performance,(d) repeating steps (a) and (b) and calculating an actual wet-chemical treatment performance value using the calculated chemical species concentration value and the measured temperature value,(e) measuring a difference between the calculated wet-chemical treatment performance value obtained in step (d) and the target wet-chemical treatment performance value in step (c), and(f) controlling a replenishment of the chemical treatment fluid based on the measured value obtained in step (e).