PRODUCTION OF BUMPED CIRCUIT BOARD - Sumitomo Metal Electro Device Co., Ltd.

Title:

PRODUCTION OF BUMPED CIRCUIT BOARD

Document Type and Number:

Japanese Patent JP2805432

Kind Code:

B2

Abstract:

PURPOSE: To form a highly dense bump by forming a positive type photoresist layer on a circuit board, applying an exposure processing thereto by means of a photomask having a specified bump-formation pattern and further succeeding developing, bonding, photoresist eliminating, and printing in sequence.
CONSTITUTION: First, a positive type photoresist layer 12 is formed on a circuit board 11, and an exposure treatment and developing treatment are applied to the layer 12 through a photomask 13 by irradiation with an ultraviolet ray 14 so as to form recessed parts 15 like a bump-formation pattern. Next, the layer 12 is entirely irradiates with the ray 14 and the parts 15 is filled with a conductive paste 16. The paste 16 is dried to bond its solid element on the board 11. Then the layer 12 is developed to be removed, and the conductive element is printed on the board 11 by baking so as to form a bump 18. Therefore, a circuit board having such a bump that is fine and has a highly positional accuracy can be produced.

Inventors:

Shozo Otomo
Kazushige Tanaka
Koichi Uno
Yoshikazu Nakata

Application Number:

JP24084393A

Publication Date:

September 30, 1998

Filing Date:

September 28, 1993

Export Citation:

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