Qualification of the Assembly Process of Flip-Chip BGA Packages ...

More documents

Recommendations

Info

4.4.2.1 Bump Dimensions Measurements Texas Tech University, Nivetha Shivan, May 2012 Figure 4.18 shows the Solder Bump located on the metal pad on the die. Figure 4.18: Bump Dimensions � Bump pitch – Measurement of the distance between two bumps � Die passivation opening – Measurement of the opening of the Oxide/Nitride passivation layer (the layers which protect the final device metal from stress conditions) � Final metal pad – Measurement of length of the Aluminium metal pad � Under Bump Metallization size – Measurement of size of UBM (the compatible layer between the bump metallization and the final device metallization) � Bump Height � Bump Diameter 4.4.2.2 Underfill Fillet Height Measurement The underfill fillet height is the height of the underfill around the die in the vertical direction. This measurement should be done from all four sides of the package. Filler height is an important measurement criterion. It is not supposed to be more than 100% of the die thickness and creeping of the underfill material over the die should not happen due to consequences like die edge cracks. Figure 4.19 shows the underfill location in a flip chip package. Figure 4.20 shows the SEM image of the dimensions of the underfill. 45
Texas Tech University, Nivetha Shivan, May 2012 Figure 4.19: Underfill location in an FCBGA Figure 4.20: SEM Image Showing Underfill Dimensions 4.4.2.3 Solder Bump Quality Inspection Figure 4.21 shows SEM image of a crack that occurred at a solder joint between the bump and the die. Figure 4.22 shows SEM image of voids in the solder bump. 46
Page 1 and 2:
QUALIFICATION OF THE ASSEMBLY PROCE
Page 3 and 4: Texas Tech University, Nivetha Shiv
Page 11 and 12: 1.3 Requirements of an IC Package [
Page 13 and 14: 1.5.2 Tape Automated Bonding [4] Te
Page 15 and 16: 2.1 What is Qualification? [7] Texa
Page 23 and 24: 3.1.1.2 Underfill material [9] Texa
Page 41 and 42: 4.2.3 Pressure Cooker Technique [20
Page 45 and 46: 4.3.1.3 Leakage Test Texas Tech Uni
Page 53: Texas Tech University, Nivetha Shiv
Page 59 and 60: Cleaning Texas Tech University, Niv
Page 61 and 62: 6.1 Results Texas Tech University,
Page 65 and 66: . Texas Tech University, Nivetha Sh
Page 67 and 68: 6.1.2 Pre-engineering Qualification
show all

Qualification of the Assembly Process of Flip-Chip BGA Packages ...

Create successful ePaper yourself

Delete template?

Save as template?