Reliability Report

AOS Semiconductor
Product Reliability Report
AON7424
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
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This AOS product reliability report summarizes the qualification result for AON7424. Accelerated
environmental tests are performed on a specific sample size, and then followed by electrical test
at end point. Review of final electrical test result confirms that AON7424 passes AOS quality and
reliability requirements. The released product will be categorized by the process family and be
monitored on a quarterly basis for continuously improving the product quality.
Table of Contents:
I.
II.
III.
IV.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
I. Product Description:
The AON7424 combines advanced trench MOSFET technology with a low resistance package to
provide extremely low RDS (ON). This device is ideal for load switch and battery protection
applications.
-RoHs Compliant
-Halogen Free
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II. Die / Package Information:
AON7424
Standard sub-micron
Low voltage N channel process
8 leads DFN 3x3A
Cu ,Ag spot
84-1LMISR4
Au 2mils
Epoxy resin with silica filler
UL-94 V-0
Up to Level 1 *
Process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Flammability Rating
Moisture Level
Note * based on info provided by assembler and mold compound supplier
III. Result of Reliability Stress for AON7424
Test Item
Test Condition
Time
Point
Solder
Reflow
Precondition
168hr 85°°c /85%RH +3
cycle reflow @260°°c
-
HTGB
Temp = 150°°c ,
Vgs=100% of Vgsmax
168hrs
500 hrs
1000 hrs
HTRB
Temp = 150°°c ,
Vds=80% of Vdsmax
168hrs
500 hrs
1000 hrs
HAST
130 +/- 2°°c , 85%RH,
33.3 psi, Vgs = 80% of
Vgs max
Pressure Pot
Temperature
Cycle
Lot Attribution
Total
Sample
size
Number
of
Failures
1155 pcs
0
77 pcs
0
(Note A*)
1 lot
77pcs / lot
77 pcs
0
100 hrs
(Note A*)
6 lots
77pcs / lot
330 pcs
0
121°°c , 29.7psi,
RH=100%
96 hrs
(Note B**)
7 lots
55 pcs / lot
385 pcs
0
-65°°c to 150°°c ,
air to air
250 / 500
cycles
(Note B**)
8 lot
55 pcs / lot
440 pcs
0
(Note B**)
55 pcs / lot
8 lots
1 lot
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III. Result of Reliability Stress for AON7424
Continues
DPA
Internal Vision
Cross-section
X-ray
CSAM
NA
5
5
5
5
5
5
0
NA
5
5
0
Bond Integrity
Room Temp
150°°c bake
150°°c bake
0hr
250hr
500hr
40
40
40
40 wires
40 wires
40 wires
0
Solderability
245°°c
5 sec
15
15 leads
0
Note A: The HTGB and HTRB reliability data presents total of available AON7424 burn-in data
up to the published date.
Note B: The pressure pot, temperature cycle and HAST reliability data for AON7424 comes from
the AOS generic package qualification data.
IV. Reliability Evaluation
FIT rate (per billion): 137
MTTF = 833 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AON7424). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
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9
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Failure Rate = Chi x 10 / [2 (N) (H) (Af)] = 1.83 x 10
9
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MTTF = 10 / FIT = 7.30 x 10 hrs = 833 years
/ [2x2x77x168x258] = 137
Chi² = Chi Squared Distribution, determined by the number of failures and confidence interval
N = Total Number of units from HTRB and HTGB tests
H = Duration of HTRB/HTGB testing
Af = Acceleration Factor from Test to Use Conditions (Ea = 0.7eV and Tuse = 55°C)
Acceleration Factor [Af] = Exp [Ea / k (1/Tj u – 1/Tj s)]
Acceleration Factor ratio list:
Af
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
130 deg C
150 deg C
258
87
32
13
5.64
2.59
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Tjs = Stressed junction temperature in degree (Kelvin), K = C+273.16
Tju =The use junction temperature in degree (Kelvin), K = C+273.16
k = Boltzmann’s constant, 8.617164 X 10-5eV/K
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