Formation of bump

Abstract

Abstract PURPOSE:To easily form bumps having uniform and sufficient height on an electrode pad of a semiconductor element by screening and forming cream solder of a bump material on a desired substrate. CONSTITUTION:Cream solder containing solder of 63Sn-37Pb composition is prepared as a bump material, and this cream solder is screened on a glass substrate to form cream solder on positions opposite to electrode pads of a semiconductor element respectively by a uniform amount. Then after the semiconductor element 1 and the glass substrate 5 are laminated so that an Ni pad 4 of the semiconductor element 1 and a pattern of the cream solder 6 are in contact with each other, the cream solder 6 is heated to 240 deg.C and melt. Then, the semiconductor element and the glass substrate are separated and spherical solder bumps are formed on Ni electrode pads of the semiconductor element. With this method for forming bumps, bumps of uniform and sufficient height can be easily formed on the electrode pads of the semiconductor element as well as the height of the bumps can be appropriately controlled.

Inventors

• 👤 Kaoru Koiwa
• 👤 馨 小岩
• 👤 Koji Yamakawa
• 👤 晃司 山川
• 👤 Yoshimi Hisatsune
• 👤 久恒　善美
• 👤 Nobuo Iwase
• 👤 岩瀬　暢男

Bibliographic Details