SLIDE 24 33
y = 4E-06x + 0,0014 R² = 0,9837
0,01 0,02 0,03 0,04 0,05 0,06 0,07
1000 6000 11000 16000 Degradation Percentage Time/Min
Data Analysis
Trend analysis & Accelerability Verification:
y = 13,693x - 37,955 R² = 0,9494
- 13
- 12,5
- 12
- 11,5
- 11
- 10,5
- 10
- 9,5
- 9
1,8 1,9 2 2,1 Ln(degradation Rate) Ln(Voltage)
Degradation VS Time Time VS Stress
Degradation Process Model Degradation Fitting Parameter Estimation
( ) ( ) ( ) , ( ) exp ( )
l l l l
Y t B t d S t y d S a b S
Maximum Likelihood
2 1 2 2 1 1 1 1 1 1 1
( ) 1 ( , , ) exp 2 2 exp ( )
l l l
n m k lij l lij l i j lij lij m k n lij l l i j
x d S t L a b t t x a b S t
( ) ( )
l l
E Y t d S t y
( )
l
d S
LSE LSE ˆ ˆ a b
( ) exp ( ) ln ( ) ( )
l l l l
d S a b S d S a b S
1 2 2 1 1 1
1 ˆ ˆ ˆ exp ( ) ( )
l
m k n lij l l i j
x a b S t n m k t
𝑏 𝑐 𝜏2
13.112 8.278e-07
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 x 10
4
0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1
Time/Min R(t)
Reliability Prediction: Parameter estimation: