文档介绍：SITKA 689998-004 (CHTJD8A) U4G1 (PID) FA Update (Rev:06) Date: 6/02/01
1. PROBLEM DESCRIPTION
Perform EDX again for returned the SITKA 689998-004 with U4G1 BGA pad because Intel indicated the error
location.
Follow Intel's indication for pad 3 and pad 4.
Supplier also chooses pad 5, it is very close pad 3 and pad 4, to put solder ball on these pads and check if any
separation between solder ball and BGA pad. The detail location as follows,
Diagram 1.
Pad 3
Pad 3
Pad 4
Pad 4
Pad 5
Pad 5
Returned Coupon
2. SAMPLES SUBMITTED
For RTV`s x-section (Follow Intel's indicated location: Pad 3 and 4):
After EDX analysis, Supplier did find the element Mg、Ti on both pads.
The SEM photo & EDX analysis as follows:
Pad 3 Analysis
At 5kv, 150x magnification
At 5kv, 600x magnification
At 5kv, 3000x magnification
At 15 Kev
C, O, N, Mg, Al, Si, Pb, Sn, Ti
At 15 Kev
C, O, Mg , Si, Pb, Sn, Ti
Pad 4 Analysis
At 5kv, 150x magnification
At 5kv, 600x magnification
At 5kv, 3000x magnification
3. PROCESSING CONDITIONS AT FAILURE
Ti and Mg are found on the legend ink only. Refer to Rev2_Sitka FA on May. 24.
Per report with the Rev5_Sitka FA on June. 01, the result shows 20 % contamination area and more % with the legend ink on
BGA pad will cause solder joint problem.
But 10 % contamination area with position Ti % and Mg % do not