Reliability Report

AOS Semiconductor
Product Reliability Report
AOD408/AOD408L,
rev B
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
495 Mercury Drive
Sunnyvale, CA 94085
U.S.
Tel: (408) 830-9742
www.aosmd.com
Dec 1, 2005
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This AOS product reliability report summarizes the qualification result for AOD408. 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 AOD408passes 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 AOD408 uses advanced trench technology to provide excellent RDS(ON) and low gate charge.
This device is suitable for use as a load switch or in PWM applications. Standard Product
AOD408 is Pb free (meets ROHS & Sony 259 specifications). AOD408L is a Green Product
ordering option. AOD408 and AOD408L 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
±20
V
Continuous Drain
Current
TA=25°C
TA=100°C
Pulsed Drain Current
TA=25°C
Power Dissipation
TA=100°C
Power Dissipation
TA=25°C
TA=70°C
Junction and Storage
Temperature Range
Thermal Characteristics
Parameter
Maximum Junction-toAmbient
Maximum Junction-toAmbient
Maximum Junction-to-Lead
18
ID
18
IDM
40
W
60
PD
30
2.5
PDSM
1.6
TJ, TSTG
-55 to 175
Symbol
t ≤ 10s
SteadyState
SteadyState
A
RθJA
RθJL
°C
Typ
Max
Units
16.7
25
°C/W
40
50
°C/W
1.9
2.5
°C/W
2
II. Die / Package Information:
Process
AOD408
AOD408L (Green Compound)
Standard sub-micron
Standard sub-micron
low voltage N channel process low voltage N channel process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Filler % (Spherical/Flake)
Flammability Rating
Backside Metallization
Moisture Level
3 lead TO252
Copper with Solder Plate
Soft solder
2 mils Au wire
Epoxy resin with silica filler
90/10
UL-94 V-0
Ti / Ni / Ag
Up to Level 1 *
3 lead TO252
Copper with Solder Plate
Soft solder
2 mils Au 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 AOD408 (Standard) & AOD408L (Green)
Test Item
Test Condition
Time Point
Lot Attribution
Total
Sample size
Solder
Reflow
Precondition
Standard: 1hr PCT+3
cycle [email protected]°c
Green: 168hr 85°c
/85%RH+3 cycle
[email protected]°c
Temp = 150°c ,
Vgs=100% of Vgsmax
0hr
Standard: 43lots
Green: 5 lots
7315 pcs
0
6 lots
492 pcs
0
HTGB
168 / 500
hrs
(note A*)
Number of
Failures
77+5 pcs / lot
1000 hrs
HTRB
Temp = 150°c ,
Vds=80% of Vdsmax
168 / 500
hrs
6 lots
(note A*)
492 pcs
0
77+5 pcs / lot
1000 hrs
HAST
Pressure Pot
130 +/- 2°c , 85%RH, 33.3
psi, Vgs = 80% of Vgs
max
121°c , 15+/-1 PSIG,
RH=100%
100 hrs
Standard: 43 lots
Green: 4 lots
2585 pcs
0
50+5 pcs / lot
96 hrs
(note B**)
Standard: 39 lots
Green: 4 lots
2365 pcs
0
50+5 pcs / lot
Temperature
Cycle
-65°c to 150°c ,
air to air, 0.5hr per cycle
250 / 500
cycles
(note B**)
Standard: 38 lots
Green: 5 lots
2365 pcs
0
50+5 pcs / lot
(note B**)
3
Continues:
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
Note A: The HTGB and HTRB reliability data presents total of available AOD408and AOD408L
burn-in data up to the published date.
Note B: The pressure pot, temperature cycle and HAST reliability data for AOD408and AOD408L
comes from the AOS generic package qualification data.
IV. Reliability Evaluation
FIT rate (per billion): 4
MTTF = 28538 years
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 (AOD408). 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 (820) (1000) (258) + 2 (164) (500) (258)] = 4
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MTTF = 10 / FIT = 2.50 x 108hrs = 28538years
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
Tj s = Stressed junction temperature in degree (Kelvin), K = C+273.16
Tj u = The use junction temperature in degree (Kelvin), K = C+273.16
k = Boltzmann’s constant, 8.617164 X 10 -5 eV / 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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