AN0013
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AN0013
NBB Series and NDA Series Reliability
NBB Series and NDA Series Reliability
This application note provides additional information on component reliability with varying device junction temperature,
and the effect of the package used on junction temperature. This information is provided for the NBB Series HBT Broad-
band Feedback Amplifiers and NDA Series HBT Distributed Amplifiers.
Device Reliability
RFMD uses an industry-proven, high-performance, high-reliability gallium indium phosphide on gallium arsenide (InGaP/
GaAs) heterojunction bipolar transistor (HBT) technology for its NBB series and NDA series broadband amplifiers.
This process has completed in excess of 1 million device hours of accelerated life testing. The test device used has two
emitter fingers of size 3碌m by 20碌m. The device was operated at 3V and with a current density of 25KA/cm
2
. The test
device is of comparable size to device sizes in the NBB series and NDA series of components. Additionally, the operating
point, both of voltage and current, was comparable to the nominal operating point of the device. Testing was performed
at five junction temperature points (257擄C, 275擄C, 285擄C, 300擄C and 315擄C) with 50 to 100 devices tested at each tem-
perature.
Figure 1 shows the device results with extrapolation of Mean Time to Failure (MTTF) for lower junction temperatures.
Results show that for a device junction temperature of 150擄C the mean time to failure is greater than 2 million hours. For
a device junction temperature of 125擄C the mean time to failure is 30 million hours.
1.5
350
300
250
Junction Temperature ( 擄C )
200
Ea = 1.3 eV
MTTF = 3E7 Hrs
@ Tj = 125 C
1.7
1.9
2.1
2.3
2.5
100
2.7
2.9
50
30
25
Stress Condition :
3V , 25 KA/cm2
1.0E+05
1.0E+08
3.1
3.3
1.0E+04
1.0E+06
1.0E+07
1.0E+09
1000 / 擄K
150
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TECHNICAL NOTES
AND ARTICLES
1.0E+01 1.0E+02
1.0E+03
Median Time to Fail (hrs)
Figure 1. MTTF for Test Device
Copyright 1997-2002 RF Micro Devices, Inc.
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