| United States Patent | 5,828,031 |
| Pattanaik | Oct. 27, 1998 |
Abstract
A method for forming electrical solder connections between a thin film magnetic head transducer and the conductors in an integrated suspension after the head has been mechanically attached to a suspension. A solder ball is placed between the head and conductor termination pads. A focused laser beam is used to produce solder reflow. The resulting solder connection has a very fine grain structure and includes a pair of extremely thin layers of intermetallic compounds in the regions where the solder connection abuts the head and conductor termination pads. The solder connection has excellent mechanical properties and reliability. The method avoids the creation of solder bumps during the wafer stage, and therefore the component processing cost is low, and the process is both fast and manufacturable.
| Inventors: | Pattanaik; Surya (San Jose, CA). |
| Assignee: | International Business Machines Corporation (Armonk, NY). |
| Appl. No.: | 670,551 |
| Filed: | Jun. 27, 1996 |
| Intl. Cl. : | B23K 26/00 |
| Current U.S. Cl.: | 219/121.63; 360/103 |
| Field of Search: | 219/121.63, 121.64, 121.85; 360/103, 104; 427/328; 257/745; 361/707, 794; 228/180.21, 248.1, 180.22; 438/108 |
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