Using underfill or flux to promote placing and parallel bonding of light emitting diodes

US10964867B2 · kind B2 · utility

Assignee

• Facebook Technologies, LLC · US

Inventors

• Daniel Brodoceanu · Cork, IE
• Thiago Martins Amaral · Riegelsberg, DE
• Pooya Saketi · Cork, IE
• Patrick J. Hughes · Cork, IE
• Alexander Udo May · Sankt Ingbert, DE
• Karsten Moh · Riegelsberg, DE
• Oscar Torrents Abad · Cork, IE

Key dates

• Filing date: May 29, 2019
• Grant date: Mar 30, 2021
• Expiry date: May 29, 2039

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H20/824
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Embodiments relate to using flux or underfill as a trapping layer for temporarily attaching light emitting diodes (LEDs) to a substrate and heating to simultaneously bond multiple LEDs onto the substrate. The flux or underfill may be selectively coated at the ends of electrodes of the LEDs prior to placing the LEDs on the substrate. Due to adhesive properties of the flux or underfill, multiple LEDs can be placed on and attached to the substrate prior to performing the bonding process. Once LEDs are placed on the substrate, the flux or underfill facilitates formation of metallic contacts between electrodes of the LED and contacts of the substrate during the bonding process. By using the flux or underfill, the formation of metallic contacts can be performed even without applying pressure.