Laser method for forming low-resistance ohmic contacts on semiconducting oxides

A method for forming an ohmic contact on an n-type semiconducting oxide, comprising:

• providing a surface of said oxide with a film of a metallic electroding material which in the molten state functions as an oxygen getter, and
• irradiating said film with a single laser pulse effecting complete melting of said film and superficial melting of said oxide in the region immediately underneath said film.

A method for forming an ohmic contact on a semiconducting-oxide body containing a p-n junction, comprising:

• providing a surface of said body with a film of metallic electroding material, said film having a thickness in the range of from about 0.5 to 1.5 .mu.m, and
• irradiating said film with one of (a) a pulse generated by a Q-switched ruby laser, said pulse having an energy density in the range of from about 1.0 to 1.5 J cm.sup.-2 and a duration of from about 15 to 25 nanoseconds and (b) a pulse generated by a Q-switched Nd-YAG laser, said pulse having an energy density in the range of from about 5 to 7 J cm.sup.-2 and a duration of from about 100 to 110 nanoseconds, to effect complete melting of said film and localized melting of the surface layer of said oxide in facial contact with said film.

A method for forming an ohmic contact on barium titanate, comprising:

• depositing on said oxide a film of metallic electroding material, and
• irradiating said film with a Q-switched laser pulse effecting melting of said film and localized melting of the surface layer of said oxide underlying said film.