Title:
PREPARATION OF PASSIVATION FILM
Document Type and Number:
Japanese Patent JPS58154237
Kind Code:
A
Abstract:
PURPOSE:To form a homogeneous film within a short period by forming an Al2O2 film through anode oxidation of Al film formed on an SiO2 film with a constant current power source and by detecting completion of film formation from increase of power supply voltage. CONSTITUTION:An SiO2 film 2 is formed in a wired IC and an Al film 3 is formed thereon. An IC is then dipped into an electrolyte 5, the Al film 3 is used as the anode and an electrode material such as platinum is used as a cathode 4, a constant current power supply 6 and a voltmeter 7 are connected between both electrodes, and thereby a closed loop is formed. At this time, a voltage rises linearly as the Al is oxidized and an Al2O3 is formed. But, when the Al3 is all replaced with an Al2O3, a current path existing between the SiO2 and Al2O3 disappears and a voltage rises rapidly. At this time, supply of power source is stopped, thus completing fabrication. The Al2O3 film becomes homogeneous since the oxidation is carried out by a constant current and fabrication period can be curtailed since the end of process can be detected easily.
Inventors:
IMAI YUUJI
Application Number:
JP3695282A
Publication Date:
September 13, 1983
Filing Date:
March 09, 1982
Export Citation:
Assignee:
TDK ELECTRONICS CO LTD
International Classes:
C25D11/04; H01L21/316; (IPC1-7): C25D11/04