METHOD OF MANUFACTURING ULTRA-THIN FILM SOI WAFER HAVING EXACT THICKNESS

摘要

PURPOSE: A method of manufacturing an ultra-thin film SOI(Silicon On Insulator) wafer is provided to obtain a silicon layer having an exact thickness without damage by performing a conventional etching process using adjusted process variables. CONSTITUTION: An SOI wafer is loaded in a vacuum chamber of an etching apparatus and a cycle number is initialized(301). The chamber is vacuumized to less than 10¬-6 torr(302). Etching gas is flowed into the chamber in order to be adsorbed on the wafer and the cycle number is added as much as one(303). The residual gas is firstly exhausted from the chamber(304). The wafer is etched by using plasma beam(305). The irradiation of plasma beam is stopped and non-reactive etching gas is secondly exhausted(306). The cycle number is compared with a reference number(307). If the cycle number is less than or the same as the reference number, the etching step is repeatedly performed in a predetermined range. In the predetermined range, a value obtained by dividing the total cycle number into an etching thickness, is invariable due to adjusted process variables. If the cycle number is more than the reference number, the vacuum of the chamber is broken(308).