Reliability Report

AOS Semiconductor
Product Reliability Report
AON3402/AON3402L,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
Dec 20, 2006
1
This AOS product reliability report summarizes the qualification result for AON3402. 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 AON3402 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.
V.
Product Description
Package and Die information
Environmental Stress Test Summary and Result
Reliability Evaluation
Quality Assurance Information
I. Product Description:
The AON3402 uses advanced trench technology to provide excellent RDS(ON), low gate charge
and operation with gate voltages as low as 1.8V while retaining a 12V VGS(MAX) rating. It is ESD
protected to a 2KV HBM rating. This device is suitable for use as load switch and general
purpose FET application. Standard Product AON3402 is Pb-free (meets ROHS& Sony 259
specifications). AON3402 and AON3402L are electrically identical.
Absolute Maximum Ratings TA=25°C unless otherwise noted
Parameter
Symbol
Maximum
Units
Drain-Source Voltage
VDS
20
V
Gate-Source Voltage
VGS
± 12
V
Continuous Drain
Current
TA=25°C
TA=70°C
Pulsed Drain Current
TA=25°C
Power Dissipation
TA=70°C
Junction and Storage
Temperature Range
Thermal Characteristics
Parameter
Maximum Junction-toAmbient
Maximum Junction-toAmbient
Maximum Junction-to-Lead
12
ID
9.6
IDM
40
3
PD
W
1.9
TJ, TSTG
-55 to 150
Symbol
T ≤ 10s
SteadyState
SteadyState
A
RθJA
RθJL
°C
Typ
Max
Units
32
42
°C/W
65
100
°C/W
25
35
°C/W
2
II. Die / Package Information:
Process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Filler % (Spherical/Flake)
Flammability Rating
Backside Metallization
Moisture Level
AON3402
AON3402L (Green Compound)
Standard sub-micron
Low voltage N channel process
DFN 3×3
Copper with Ag spot
Ag epoxy
Au 2mils
Epoxy resin with silica filler
90/10
UL-94 V-0
Ti / Ni / Ag
Up to Level 1 *
Standard sub-micron
Low voltage N channel process
DFN 3×3
Copper with Ag spot
Ag epoxy
Au 2 mils
Epoxy resin with silica filler
100/0
UL-94 V-0
Ti / Ni / Ag
Up to Level 1*
Note * based on info provided by assembler and mold compound supplier
III. Result of Reliability Stress for AON3402 (Standard) & AON3402L (Green)
Test Item
Test Condition
Time
Point
Solder
Reflow
Precondition
Standard: 1hr PCT+3
cycle reflow@260°c
Green: 168hr 85°c
/85%RH +3 cycle reflow
@260°c
Temp = 150°c ,
Vgs=100% of Vgsmax
0hr
HTGB
168 / 500
hrs
1000 hrs
HTRB
Temp = 150°c ,
Vds=80% of Vdsmax
168 / 500
hrs
1000 hrs
HAST
Pressure Pot
Temperature
Cycle
130 +/- 2°c , 85%RH,
33.3 psi, Vgs = 80% of
Vgs max
121°c , 29.7psi,
100%RH
-65°c to 150°c ,
air to air
Lot Attribution
Standard: 5 lots
Green: 8 lots
(Note B**)
5 lots
(Note A*)
5 lots
100 hrs
(Note A*)
Standard: 5 lots
Green: 6 lots
96 hrs
(Note B**)
Standard: 4 lots
Green: 7 lots
250 / 500
cycles
(Note B**)
Standard: 3 lots
Green: 8 lot
(Note B**)
Total
Sample
size
Number
of
Failures
1815 pcs
0
410 pcs
0
77+5 pcs /
lot
410 pcs
0
77+5 pcs /
lot
605 pcs
0
50+5 pcs /
lot
605 pcs
0
50+5 pcs /
lot
605 pcs
0
50+5 pcs /
lot
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III. Result of Reliability Stress for AON3402 (Standard) & AON3402 L (Green)
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
Die shear
150°c
0hr
10
10
0
Note A: The HTGB and HTRB reliability data presents total of available AON3402 and
AON3402L burn-in data up to the published date.
Note B: The pressure pot, temperature cycle and HAST reliability data for AON3402 and
AON3402L comes from the AOS generic package qualification data.
IV. Reliability Evaluation
FIT rate (per billion): 4.3
MTTF = 26547 years
In general, 500 hrs of HTGB, 150 deg C accelerated stress testing is equivalent to 15 years of
lifetime at 55 deg C operating conditions (by applying the Arrhenius equation with an activation
energy of 0.7eV and 60% of upper confidence level on the failure rate calculation). AOS reliability
group also routinely monitors the product reliability up to 1000 hr at and performs the necessary
failure analysis on the units failed for reliability test(s).
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AON3402). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
Failure Rate = Chi2 x 109 / [2 (N) (H) (Af)] = 1.83 x 109 / [2 (5×164) (1000) (258)] = 4.3
MTTF = 109 / FIT = 2.32 x 108hrs = 26547 years
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
1
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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V. Quality Assurance Information
Acceptable Quality Level for outgoing inspection: 0.1% for electrical and visual.
Guaranteed Outgoing Defect Rate: < 25 ppm
Quality Sample Plan: conform to Mil-Std-105D
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