Reliability Report

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AOS Semiconductor
Product Reliability Report
AON4703/AON4703L,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
10 Jan, 2006
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This AOS product reliability report summarizes the qualification result for AON4703. 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 AON4703 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 AON4703 uses advanced trench technology to provide excellent RDS(ON) and low gate charge.
A Schottky diode is provided to facilitate the implementation of a bidirectional blocking switch, or
for DC-DC conversion applications. Standard Product AON4703 is Pb-free (meets ROHS & Sony
259 specifications). AON4703L is a Green Product ordering option. AON4703 and AON4703L are
electrically identical.
Absolute Maximum Ratings TA=25°C unless otherwise noted
Parameter
Symbol
MOSFET
Schottky
Units
Drain-Source Voltage
VDS
-20
V
Gate-Source Voltage
VGS
±8
V
Continuous Drain
Current
TA=25°C
-3.4
ID
-2.7
Pulsed Drain Current
IDM
-15
Schottky reverse voltage
VKA
Continuous Forward
Current
TA=70°C
TA=25°C
TA=70°C
A
1.9
IF
TA=25°C
Power Dissipation
TA=70°C
Junction and Storage
Temperature Range
7
PD
TJ, TSTG
Parameter: Thermal Characteristics
MOSFET
Maximum Junction-toT ≤ 10s
Ambient
Maximum Junction-toSteadyAmbient
State
SteadyMaximum Junction-to-Lead
State
A
1.2
IFM
Pulsed Forward Current
V
20
Symbol
RθJA
RθJC
1.7
0.96
1.1
0.62
-55 to 150
-55 to 150
W
°C
Typ
Max
Units
51
75
°C/W
88
110
°C/W
28
35
°C/W
2
Thermal Characteristics Schottky
Maximum Junction-toT ≤ 10s
Ambient
Maximum Junction-toSteadyAmbient
State
SteadyMaximum Junction-to-Lead
State
Symbol
RθJA
RθJC
Typ
Max
Units
66
80
°C/W
95
130
°C/W
40
50
°C/W
II. Die / Package Information:
Process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Filler % (Spherical/Flake)
Flammability Rating
Backside Metallization
Moisture Level
AON4703
AON4703L (Green Compound)
Standard sub-micron
Standard sub-micron
Low voltage P channel process Low voltage P channel process
DFN 3X2
DFN 3X2
Copper with Ag spot
Copper with Ag spot
Ag epoxy
Ag epoxy
Au 2mils
Au 2 mils
Epoxy resin with silica filler
Epoxy resin with silica filler
100/0
90/10
UL-94 V-0
UL-94 V-0
Ti / Ni / Ag
Ti / Ni / Ag
Up to Level 1 *
Up to Level 1*
Note * based on info provided by assembler and mold compound supplier
III. Result of Reliability Stress for AON4703 (Standard) & AON4703L (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
HTRB
HAST
Pressure Pot
Temperature
Cycle
Temp = 150°c ,
Vds=80% of Vdsmax
130 +/- 2°c , 85%RH,
33.3 psi, Vgs = 80% of
Vgs max
121°c , 29.7psi,
RH=100%
-65°c to 150°c ,
air to air,
Lot Attribution
Number
of
Failures
1760 pcs
0
(Note B**)
6 lots
492 pcs
0
1000 hrs
(Note A*)
77+5 pcs /
lot
168 / 500
hrs
1000 hrs
6 lots
168 / 500
hrs
100 hrs
96 hrs
250 / 500
cycles
Standard: 3 lots
Green: 9 lots
Total
Sample
size
(Note A*)
Standard: 3 lots
Green: 7 lots
(Note B**)
Standard: 3 lots
Green: 8 lots
(Note B**)
Standard: 2 lots
Green: 9 lot
(Note B**)
492 pcs
0
77+5 pcs /
lot
550 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 AON4703 (Standard) & AON4703L (Green)
Continued
Internal Vision
Cross-section
X-ray
DPA
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 AON4703 and
AON4703L burn-in data up to the published date.
Note B: The pressure pot, temperature cycle and HAST reliability data for AON4703 and
AON4703L comes from the AOS generic package qualification data.
IV. Reliability Evaluation
FIT rate (per billion): 16
MTTF = 7134 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 (AON4703). 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) (168) (258) + 2 (164) (500) (258)] = 16
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MTTF = 10 / FIT = 6.25 x 107hrs = 7134 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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