Reliability Report

AOS Semiconductor
Product Reliability Report
AOD404 / AOD404L,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
Nov 7, 2005
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This AOS product reliability report summarizes the qualification result for AOD404/AOD404L.
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 AOD404/AOD404L
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 AOD404 uses advanced trench technology to provide excellent RDS(ON), low gate charge and
low gate resistance. This device is ideally suited for use as a high side switch in CPU core power
conversion. Standard Product AOD404 is Pb-free (meets ROHS & Sony 259 specifications).
AOD404L is a Green Product ordering option. AOD404 and AOD404L are electrically identical.
Absolute Maximum Ratings TA=25°C unless otherwise noted
Parameter
Symbol
Maximum
Units
Drain-Source Voltage
VDS
-30
V
Gate-Source Voltage
VGS
±12
V
Continuous Drain
Current
TA=25°C
TA=100°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
85
ID
65
IDM
200
A
100
PD
W
50
TJ, TSTG
-55 to 175
Symbol
t ≤ 10s
SteadyState
SteadyState
RθJA
RθJL
°C
Typ
Max
Units
14.2
20
°C/W
39
50
°C/W
0.8
1.5
°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
AOD404
Standard sub-micron
low voltage N channel process
3 lead TO252
Copper with Solder Plate
Silver-filled Epoxy
5 & 8 mils Al wire
Epoxy resin with silica filler
90/10
UL-94 V-0
Ti / Ni / Ag
Up to Level 1 *
AOD404L (Green Compound)
Standard sub-micron
low voltage N channel process
3 lead TO252
Copper with Solder Plate
Silver-filled Epoxy
5 & 8 mils Al wire
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 AOD404 (Standard) & AOD404L (Green)
Test Item
Solder
Reflow
Precondition
HTGB
Time Point
Lot Attribution
Standard: 1hr PCT+3
cycle IR reflow@260 °c
Green: 168hr 85/85
THB+3 cycle IR
reflow@260 °c
0hr
Standard: 48 lots
Green: 16 lots
Temp = 150 °c,
Vgs=100% of Vgsmax
168 / 500
hrs
Test Condition
Total
Sample size
Number of
Failures
9405 pcs
0
4 lots
328 pcs
0
(note A*)
77+5 pcs / lot
1000 hrs
HTRB
Temp = 150 °c,
Vds=80% of Vdsmax
168 / 500
hrs
1000 hrs
HAST
Pressure Pot
Temperature
Cycle
130 +/- 2 °c, 85%, 33.3
psi, Vgs = 80% of Vgs
max
100 hrs
121 °c, 15+/-1 PSIG,
RH=100%
96 hrs
-65 to 150 °c,
air to air, 0.5hr per
cycle
250 / 500
cycles
4 lots
328 pcs
0
(note A*)
Standard: 1 lot
Green: 3 lots
(note B**)
Standard: 1 lot
Green: 3 lots
(note B**)
Standard: 1 lot
Green: 3 lots
(note B**)
77+5 pcs / lot
220 pcs
(3 lots)
0
50+5 pcs / lot
220 pcs
(3 lots)
0
50+5 pcs / lot
220 pcs
(3 lots)
0
50+5 pcs / lot
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III. Result of Reliability Stress for AOD404 (Standard) & AOD404L (Green),
conintues
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
230°C
5 sec
15
15 leads
0
0hr
10
10
0
Die Shear
Note A: The HTGB and HTRB reliability data presents total of available AOD404 and AOD404L
burn-in data up to the published date.
Note B: The pressure pot, temperature cycle and HAST reliability data for AOD404 and
AOD404L comes from the AOS generic package qualification data.
IV. Reliability Evaluation
FIT rate (per billion): 21
MTTF = 5436 years
500 hrs of HTGB / HTRB, 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 (AOD404). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
2
Failure Rate = Chi x 10
9
/ [2 (N) (H) (Af)] = 1.83 x 109 / [2 (656) (168) (258)] =32
MTTF = 109 / FIT = 4.76 x 107hrs = 5436 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°c
70°c
85°c
100°c
115°c
130°c
150°c
258
87
32
13
5.64
2.59
1
4
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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