Non-contact automatic height sensing using air pressure for die bonding
US6376265B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Apr 5, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/014
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is provided for bonding a semiconductor die to a substrate, such as bonding an upper die to the lower semiconductor die of a stacked die assembly. Embodiments include a die bonder with an air pressure sensor for directing a jet of air to the top surface of the lower die. The air pressure sensor generates a signal indicative of the height of the top surface of the lower die based on the back pressure of the jet of air, and sends the signal to a controller for accurately setting the descending height of the upper die onto the lower die to produce the required gap between the two dies for die bonding. Since the sir pressure sensor only contacts the substrate with a relatively small jet of air, the top surface of the lower die is not damaged by the sensor. Because the air pressure sensor accurately measures the height of the lower die, the upper die is placed above the lower die with the proper gap, despite variations in the height of the lower die. As a result, damage to the dies during assembly is reduced, thereby increasing manufacturing yield and reducing production costs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.