Epoxy bonding (air, with alignment): View

on front Epoxy bonding (air, with alignment)

on front

Thickness	5 .. 8 µm

on front

Process characteristics:

Alignment type

Optical implies front-front align.
Backside IR implies front-back align.
Manual implies no fine alignment.

Perform piranha clean

If there are no metal parts on any of the wafers select standard piranha clean, otherwise an organic NMP clean will be performed.

Alignment tolerance

Registration of CAD data to features on wafer

5 .. 8 µm

Ambient

Ambient to which substrate is exposed during processing

air

Batch size

Bonded materials

Pair of materials bonded by this process

glass (Hoya), Pyrex (Corning 7740), silicon, silicon on insulator

Pressure

Pressure of process chamber during processing

1 atm

Wafer size

Comments:

A proprietary epoxy is used in this step.
It is possible to selectively coat on raised microstructures on wafers.
Selective epoxy coating available on samples with 20um+ topography.
Epoxy characteristics:
Shore D Hardness: 80-85
Lap Shear Strength: psi @ 23°C
Die Shear Strength: >10Kg/3,400 psi
Degradation Temp: 381°C
Operating Temp:
Continuous: -55 to 125°C
Intermittent: -55 to 300°C
Glass Transition Temp (Tg): 104°C
Coeff. of Thermal Expansion (CTE):
Below Tg: 55 ´ 10 -6 in/in/°C
Above Tg: 220 ´ 10 -6 in/in/°C
Storage Modulus: 354,000 psi