Reliability Report

AOS Semiconductor
Product Reliability Report
AOI508,
rev A
Plastic Encapsulated Device
ALPHA & OMEGA Semiconductor, Inc
www.aosmd.com
1
This AOS product reliability report summarizes the qualification result for AOI508. 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 AOI508 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:
General Description
• Latest Trench Power MOSFET technology
• Very Low RDS(on) at 10VGS
• Low Gate Charge
• High Current Capability
• RoHS and Halogen-Free Compliant
Application
• DC/DC Converters in Computing
• Isolated DC/DC Converters in Telecom and Industrial
Detailed refer to the datasheet.
II. Die / Package Information:
Process
Package Type
Lead Frame
Die Attach
Bond wire
Mold Material
Moisture Level
AOI508
Standard sub-micron
Low voltage N channel process
TO251A
Bare Cu
Soft solder
Al & Au wire
Epoxy resin with silica filler
Up to Level 1 *
Note * based on info provided by assembler and mold compound supplier
2
III. Result of Reliability Stress for AOI508
Test Item
Test Condition
Time
Point
Lot
Attribution
Total
Sample
size
Solder
Reflow
Precondition
HTGB
168hr 85°°c
/85%RH +3 cycle
reflow@260°°c
-
3 lots
495pcs
0
JESD22A113
Temp = 150°°c ,
Vgs=100% of
Vgsmax
168hrs
500 hrs
1000 hrs
1 lot
308pcs
0
JESD22A108
Temp = 150°°c ,
Vds=80% of
Vdsmax
168hrs
500 hrs
1000 hrs
77 pcs / lot
308pcs
0
JESD22A108
HAST
130°°c , 85%RH,
33.3 psi, Vgs =
100% of Vgs max
100 hrs
(Note A*)
3 lots
77 pcs / lot
165pcs
0
JESD22A110
Pressure Pot
121°°c , 29.7psi,
RH=100%
96 hrs
(Note A*)
3 lots
55 pcs / lot
165pcs
0
JESD22A102
(Note A*)
55 pcs / lot
0
JESD22A104
HTRB
Temperature
Cycle
-65°°c to 150°°c ,
air to air
250 / 500
cycles
Number
of
Failures
Standard
3 lots
(Note A*)
1 lot
3 lots
3 lots
165pcs
(Note A*)
55 pcs / lot
Note A: The reliability data presents total of available generic data up to the published date.
IV. Reliability Evaluation
FIT rate (per billion): 7
MTTF = 15704 years
The presentation of FIT rate for the individual product reliability is restricted by the actual burn-in
sample size. Failure Rate Determination is based on JEDEC Standard JESD 85. FIT means one
failure per billion device hours.
2
9
Failure Rate = Chi x 10 / [2 (N) (H) (Af)]
9
= 1.83 x 10 / [2x (2x77x168+6x77x1000) x258] = 7
9
8
MTTF = 10 / FIT =1.38 x 10 hrs = 15704 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
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
3