Ion etching method

Abstract

Abstract PURPOSE:To selectively etch high melting-point metals such as silicon, molybdenum, tungsten, etc. of monocrystal and multicrystal form and their silicides in a sample chamber with gaseous ion by introducing a single gas of halogen element in to an electric discharge chamber and dissociating it. CONSTITUTION:A permanent magnet 7 is deposited in the center of a cathode 6 and a magnetic field and a DC field between an anode 1 and a cathode 6 are caused to directly cross each other in an electric discharge clearance 2. Cl2 is introduced 3 and impacted by an electronic cycloid motion so that it is ionized to become a plasma. If the cathode 6 is maintained at a negative potential, a positive ion beam 5 is pulled out of a window 4, etching an objected to be etched 12 on a rotary table 14 inside a sample chamber. If an incident angle is set at theta and a gas containing carbon and halogen such as CCl4 is used as an etching gas to etch silicon oxide and silicon, silicon is quickly etched because the reactivity of dissociated Cl atom and silicon oxide is low. If bromine and iodine are used, the selectivity of silicon oxide is further enhanced, thus enabling a high-speed and selective etching.

Inventors

• 👤 Haruo Okano
• 👤 Yasuhiro Horiike

Bibliographic Details