Wafer Bumping
Gold Bumping Solder Bumping Pillar Bumping Pad Redistribution (RDL)  

Pillar Bumping


Pillar Bump Guidelines


Design Guidelines Pillar Bumps
(with Eutectic or Lead-free cap)
1
 Bump Shape Octagonal
2
 Pillar Structure Copper post + solder cap
3
Bump Height: Copper post
65 µm
4
Bump Height: Solder cap
35 µm
5
 Total Bump Height Co Planarity +/- 5 µm (in die), +/- 10µm (in water), +/- 15 µm (wf to wf)
6
 Bump Pitch 80 µm Minimum
7
 Bump Spacing 33 µm Minimum
8
 Bump Pad to Pass. Overlap 7 µm Per Side Minimum
9
 Bond Pad to Pass. Opening 14 µm Per Side Minimum
10
 Passivation Type Nitride, OxyNitride, Polyimide
11
 Incoming Wafer Edge Exclusion Zone 5 mm (from wafer edge) for 6" and 8" wafer
12
 Solder Cap Material 63Sn/37Pb +/- 5%, 100Sn
13
 UBM Material

Ti + Cu
14
 Shear Testing Height 30 µm above wafer surface
15
 Shear Strength >7.5 mgf/µm² for copper post
16
 Wall angle 83 degree for aligner, 87 degree for Ultratech Stepper
17
 Bump Mask Design and Layout APS In-House Design Capability: Require GDSII, Stepping Distance, Wafer Map


Pillar Bump Structure

Standard Copper Pillar Bump
Fine Pitch Copper Pillar Bump

APS Pillar Bump  
The patented Pillar Bump for standard pitch is made up of 65um non-reflowable Cu post capped with 35um solder. This unique structure ensures the Pillar Bump’s distinctive advantages compared to standard Eutectic or High Lead Solder bumps.

Advantages of Pillar Bump:
1.
Cu post ensures a high standoff of 70-80um
2.
Controlled solder amount allows for
solder-maskless substrates
3.
Suitable for use on bare Cu pads
4.
Rigid sidewalls of Cu post ensures ease of underfilling
5.
Cu post permits better thermal and electrical performance
6.
Cu post increases the self-attenuation distance of alpha particles offering soft-error protection
7.
Lead-free option available


Key Advantages of Pillar Bump

Fine-Pitch Solution
Pillar bumping permits cost-effective fine-pitch bumping with very predictable standoff distances for better underfilling while improving thermal and electrical performances compared to standard eutectic or high-lead solder bumps. The fine-pitch Pillar Bump has a 55um Cu post capped with 25um solder. This structure has all the advantages of a standard pitch Pillar Bump and maintains a high standoff of 60-70um after assembly.


Unique Pillar Structures
The Pillar Bump has also evolved into various shapes for specific applications in the semiconductor industry. This opens up a new dimension for performance enhancement through changes in the die design enable by these Unique Pillar Structures.

  • Bar Bumps (capable of up to 1400um)
  • Rectangular Bumps
    (with internal or external regular bumps
 
  Bar Bumps
   
 
  Rectangular Bumps

Contact us for more information now!
Advanpack Solutions Pte Ltd
© 2002 All Rights Reserved.
Best viewed in 1024X768 screen resolution.