LGA Board Level Reliability

µModule LGA
Level 2 Interconnect
Reliability Data
CONTENTS
May 2013
Demo Board Details………………………………………….…...…….2
Demo Board Reliability Results.…………………………...………….3, 4
Rider Card Details………………………………………….….….…….5
Rider Card Reliability Results.…………………………...………...….6
Daisy Chain Board Details……………………………………….…....7
Daisy Chain Board Reliability Results…..……………………………8-11
LTC Demo Board Details
PCB Material
# Metal Layers
Board Size
Thickness
Pad Type
Pad Finish
Pad Size
Soldermask opening
Soldermask
thickness
Method for
Detecting
Interconnect Failure
FR-4
2
4 3/4" x 3"
62 mils or 93 mils (see details)
NSMD
NiAu
0.635mm
0.686mm
0.02 - 0.03mm
Bench set-up,
Functional test
Page 2
DEMO BOARD MOUNT TEMP CYCLE DATA FOR THE LTM46XX FAMILY (15mmX15mm)
DEVICE
CYCLES CYCLES
ON TC
ON TC
-40°C
-40°C
DATE DEVICE
PKG
BOARD
SAMPLE BENCH
TO
TO
SOLDER
CODE TYPE
TYPE THICKNESS
SIZE
REJECTS +125°C
+125°C
PASTE
0513
0525
0546
0623
0738
0846
LTM4600
LTM4600
LTM4600
LTM4601
LTM4616
LTM4617
6
LOTS
DATE DEVICE
CODE TYPE
0715
0632
LTM4600
LTM4601
2
LOTS
DATE DEVICE
CODE TYPE
0624
0624
LTM4600
LTM4600
2
LOTS
LGA-104
LGA-104
LGA-104
LGA-118
LGA-144
LGA-144
PKG
TYPE
LGA-104
LGA-118
PKG
TYPE
LGA-104
LGA-104
62 mils
62 mils
62 mils
62 mils
62 mils
62 mils
99
96
93
88
96
77
0
0
0
0
0
0
549
0
2,000
2,000
2,000
2,000
2,000
1,500
198,000
192,000
186,000
176,000
192,000
115,500
SnPb
SnPb
SnAgCu
SnAgCu
SnAgCu
SnAgCu
1,059,500
* 10 °C per minute ramp rate
* 10 minute dwell time
DEVICE
CYCLES CYCLES
ON TC
ON TC
BOARD
SAMPLE BENCH
0°C TO
0°C TO SOLDER
THICKNESS
SIZE
REJECTS +100°C
+100°C
PASTE
62 mils
62 mils
40
44
0
0
84
0
5,000
3,500
200,000
154,000
SnAgCu
SnPb
354,000
* 10 °C per minute ramp rate
* 10 minute dwell time
DEVICE
CYCLES CYCLES
ON TC
ON TC
-55°C
-55°C
BOARD
SAMPLE BENCH
TO
TO
SOLDER
THICKNESS
SIZE
REJECTS +125°C
+125°C
PASTE
62 mils
62 mils
65
76
0
0
141
0
1,500
1,500
97,500
114,000
211,500
* 10 °C per minute ramp rate
* 10 minute dwell time
Page 3
SnPb
SnPb
DEMO BOARD MOUNT TEMP CYCLE DATA FOR THE LTM46XX FAMILY (15mmX9mm)
DEVICE
CYCLES CYCLES
ON TC
ON TC
-40°C
-40°C
TO
TO
SOLDER
DATE DEVICE PKG
BOARD
SAMPLE
ATE
CODE TYPE
TYPE THICKNESS
SIZE
REJECTS +125°C
+125°C
PASTE
0714
0714
0728
0729
LTM4604
LTM4604
LTM4608
LTM4608
4
LOTS
LGA-66
LGA-66
LGA-68
LGA-68
62 mils
62 mils
93 mils
93 mils
79
79
116
116
0
0
0
0
390
0
2,000
2,000
1,000
1,000
158,000
158,000
116,000
116,000
SnPb
SnAgCu
SnPb
SnAgCu
548,000
* 10 °C per minute ramp rate
* 10 minute dwell time
Page 4
Rider Card PCB Details
PCB Material
# Metal Layers
Board Size
Thickness
Pad Type
Pad Finish
Pad Size
Soldermask opening
Soldermask
thickness
Method for
Detecting
Interconnect Failure
FR-4 or Polyimide
4
1 1/2" x 1 1/4"
93 mils
NSMD
NiAu
0.635mm
0.686mm
0.02 - 0.03mm
ATE,
Functional test
Page 5
RIDER CARD MOUNT TEMP CYCLE DATA FOR THE LTM80XX FAMILY
DATE DEVICE
CODE
TYPE
0723
0723
LTM8023
LTM8023
2
LOTS
PKG
TYPE
LGA-50
LGA-50
BOARD
SAMPLE
THICKNESS
SIZE
93 mils
93 mils
114
107
0
221
ATE
REJECTS
CYCLES
ON TC
-40°C
TO
+125°C
0
0
2,000
2,000
DEVICE
CYCLES
ON TC
-40°C
TO
SOLDER
+125°C
PASTE
228,000
214,000
0
442,000
* 10 °C per minute ramp rate
* 10 minute dwell time
Page 6
SnPb
SnAgCu
Daisy-Chain PCB Details
Material
# Metal Layers
Board Size
Thickness
Pad Type
Pad Finish
Pad Size
Soldermask opening
Soldermask
thickness
FR-4
6
6 1/4" x 6 1/4"
93 mils
SMD
NiAu
0.730mm x 0.730mm
0.630mm x 0.630mm
0.035mm ± 0.010mm
Daisy-Chain Test Details
Tests Conform to
Ramp Rate
Dwell Time
IPC-9701A
10°C / minute
10 minutes
Method for Detecting
Interconnect Failure
Daisy Chain
with Real-Time Resistivity Monitor
Page 7
DAISY CHAIN TEMP CYCLE DATA
DATE
CODE
DEVICE
TYPE
PKG
TYPE
SAMPLE
SIZE
CONTINUITY
REJECTS
CYCLES
ON TC
0°C TO
+100°C
0640
0640
0748
0748
0847
0911
0927
1007
1027
1224
LTM4600
LTM4600
LTM4601A
LTM4601A
LTM2880
LTM9004
LTM4617
LTM2885
LTM4620
LTM4676
LGA-104
LGA-104
LGA-133
LGA-133
LGA-68
LGA-204
LGA-133
LGA-32
LGA-144
LGA-144
30
30
40
40
80
40
40
40
40
40
21
0
5
0
0
0
0
2
0
0
3,500
4,000
6,000
3,500
3,500
6,000
6,000
6,000
6,000
6,000
10
LOTS
420
28
DEVICE
CYCLES
ON TC
0°C TO
+100°C
SOLDER
PASTE
105,000
120,000
240,000
140,000
280,000
240,000
240,000
240,000
240,000
240,000
PbSn
SnAgCu
PbSn
SnAgCu
SnAgCu
SnAgCu
SnAgCu
SnAgCu
SnAgCu
SnAgCu
2,085,000
LTM46xx μModule Footprint Comparisons
Page 8
LTM4600 Daisy Chain Failure Analysis
99% 4826 cycles.
1%, 1380 cycles Weibull plot for LTM4600 daisy chain Pb board mounted units after 0/100C 3500 cycles test.
No failures found from PbF solder paste (up to 4000 T/C)
Solder Fatigue and Edge Crack found at Corner Pin after 3500 cycles (Pb solder paste).
Page 9
LTM4601A Daisy Chain Failure Analysis
1%, 1780 cycles Weibull plot above for LTM4601A Daisy Chain Pb board mounted units after 0/+100°C, 6000 cycles test.
No failures found from PbF solder paste up to 3500 cycles. Cross-section above shows good solder joint integrity.
Page 10
LTM2885 Daisy Chain Failure Analysis
1%, 3470 cycles
PCB side LGA Package side
Dye and pry after 6000 cycles shows A1 corner pin saturated. This DUT failed at 3773 cycles. Presence of dye indicates a solder joint
failure at the A1 pin location.
Page 11