Title:
BALL MOUNTING METHOD AND TRANSFER SUBSTRATE
Document Type and Number:
Japanese Patent JP3045133
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a ball mounting method by which balls can be mounted easily on a wiring board or semiconductor chip having a fine irregular pattern with a high yield.
SOLUTION: At the portions respectively corresponding to the plurality of electrode pads of a wiring board or semiconductor chip on a transfer substrate 1, a plurality of annular wiring 2 is formed by photolithography. The wring 2 is electrically connected in series through a wire 2a. Each annular wiring 2 is made to generate an electromagnetic force by making a direct current to flow to the wiring 2 from a DC power source 5. Because of the electromagnetic forces, ferromagnetic balls 6 are attracted to the parts of the transfer substrate 1 where the annular wiring 2 are formed. The balls 6 are separated from the transfer substrate 1 by weakening or extinguishing the electromagnetic forces generated from the annular wiring 2 above the wiring board or semiconductor chip and the separated balls 6 are mounted on the wiring board of semiconductor chip.
Inventors:
Nobuaki Takahashi
Naoji Semba
Naoji Semba
Application Number:
JP8411198A
Publication Date:
May 29, 2000
Filing Date:
March 30, 1998
Export Citation:
Assignee:
NEC
International Classes:
B23K3/06; H01L21/60; H01L23/12; H05K3/34; (IPC1-7): H05K3/34; B23K3/06; H01L23/12
Domestic Patent References:
| JP7283521A |
Attorney, Agent or Firm:
Masaru Watanabe (3 outside)