Method of selectively transferring LED die to a backplane using height controlled bonding structures
US10714464B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2017 |
| Grant date | Jul 14, 2020 |
| Priority date | — |
| Expiry date | Jan 18, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/0364
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Selective transfer of dies including semiconductor devices to a target substrate can be performed employing local laser irradiation. Coining of at least one set of solder material portions can be employed to provide a planar surface-to-surface contact and to facilitate bonding of adjoining pairs of bond structures. Laser irradiation on the solder material portions can be employed to sequentially bond selected pairs of mated bonding structures, while preventing bonding of devices not to be transferred to the target substrate. Additional laser irradiation can be employed to selectively detach bonded devices, while not detaching devices that are not bonded to the target substrate. The transferred devices can be pressed against the target substrate during a second reflow process so that the top surfaces of the transferred devices can be coplanar. Wetting layers of different sizes can be employed to provide a trapezoidal vertical cross-sectional profile for reflowed solder material portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.