Reliability Report

AOS Semiconductor
Product Reliability Report
AOT42S60,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
1
This AOS product reliability report summarizes the qualification result for AOT42S60. 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 AOT42S60 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:
TM
The AOT42S60 has been fabricated using the advanced αMOS high voltage process that is
designed to deliver high levels of performance and robustness in switching applications. By
providing low RDS(on), Ciss and Crss along with guaranteed avalanche capability this part can be
adopted quickly into new and existing offline power supply designs.
Details refer to the datasheet.
II. Die / Package Information:
AOT42S60
Standard sub-micron
TM
600V, 37A αMOS Power Transistor
Package Type
TO220
Lead Frame
Bare Cu
Die Attach
Soft solder
Bonding
Al wire
Mold Material
Epoxy resin with silica filler
Moisture Level
Up to Level 1 *
Note * based on info provided by assembler and mold compound supplier
Process
2
III. Result of Reliability Stress for AOT42S60
Test Item
Test Condition
Time
Point
MSL
Precondition
168hr 85°c
/85%RH +3 cycle
reflow@260°c
Temp = 150°c ,
Vgs=100% of
Vgsmax
Temp = 150°c ,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
HAST
130 , 85%RH,
33.3 psi, Vgs =
100% of Vgs max
96 hrs
Pressure Pot
121°c , 29.7psi,
RH=100%
96 hrs
Temperature
Cycle
-65°c to 150°c ,
air to air,
250 / 500
cycles
HTGB
Lot
Attribution
Total
Sample
size
-
12 lots
2574pcs
0
JESD22A113
168hrs
500 hrs
1000 hrs
539pcs
0
2 lots
5 lots
JESD22A108
77 pcs / lot
539pcs
0
JESD22A108
(Note A*)
9 lots
77 pcs / lot
495pcs
0
JESD22A110
(Note A*)
9 lots
55 pcs / lot
693pcs
0
JESD22A102
(Note A*)
77 pcs / lot
0
JESD22A104
0
AEC-Q101
(Note A*)
HTRB
2 lots
5 lots
12 lots
(Note A*)
Power
Cycling
Tj=125C
4286cyc
Number
of
Failures
6 lots
(Note A*)
924pcs
Reference
Standard
77 pcs / lot
462pcs
77 pcs / lot
Note A: The reliability data presents total of available generic data up to the published date.
3
IV. Reliability Evaluation
FIT rate (per billion): 4
MTTF = 29742 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size of the selected product (AOT42S60). Failure Rate Determination is based on JEDEC
Standard JESD 85. FIT means one failure per billion hours.
2
9
Failure Rate = Chi x 10 / [2 (N) (H) (Af)]
9
= 1.83 x 10 / [2x (4x77x500 +10x77x1000) x258] = 4
9
8
MTTF = 10 / FIT =2.61 x 10 hrs = 29742 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:
55 deg C
70 deg C
85 deg C
100 deg C
115 deg C
Af
258
87
32
13
5.64
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 10-5eV / K
130 deg C
150 deg C
2.59
1
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