Laser production and product qualification via accelerated life testing based on statistical modeling
View Patent ↗A method is provided for improving performance testing in semiconductor lasers via an accelerated life model. By using an accelerated life model, operating conditions for performance tests, such as burn-in procedures and wafer qualification, are optimized with reduced cost and effort. The method is also used to improve maintenance of optical networks containing semiconductor lasers.
1. A method for performance testing comprising:
providing a semiconductor laser, wherein said semiconductor laser is mounted to allow connection of said semiconductor laser to other circuitry;
specifying a first set of performance test operating conditions, wherein said first set of performance test operating conditions includes a first performance test duration;
calculating a second set of performance test operating conditions based on an accelerated life model, wherein said second set of performance test operating conditions includes a second performance test duration; and
performing a performance test on said semiconductor laser according to said second set of performance test operating conditions.
2. The method of claim 1 , wherein the semiconductor laser is a laser diode.
3. The method of claim 1 , wherein the accelerated life model is of the form
Median Life= A*F ( I )*exp[ Ea /( kT )]
where I represents a drive current, T represents a junction temperature, A represents a process dependent constant, E a represents an activation energy (eV), and k represents Boltzmann's constant, 8.16171*10 −5 eV per ° C.
4. The method of claim 3 , wherein F(I) is of the form
F ( I )(1/ I ) B
where B represent a drive current acceleration constant.
5. The method of claim 3 , wherein calculating a second set of performance test operating conditions further comprises:
identifying a second operating current and a second operating temperature;
determining an acceleration factor based on the accelerated life model; and
calculating the second performance test duration based on the acceleration factor and the first performance test duration.
6. The method of claim 1 , wherein said performance test comprises a burn-in procedure.
7. The method of claim 1 , wherein said performance test comprises a wafer qualification procedure.
8. A laser diode product produced by the method comprising:
providing a laser diode, wherein said laser diode is mounted to allow connection of said laser diode to other circuitry;
specifying a first set of performance test operating conditions, wherein said first set of performance test operating conditions includes a first performance test duration;
calculating a second set of performance test operating conditions based on an accelerated life model, wherein said second set of performance test operating conditions includes a second performance test duration; and
performing a performance test on said laser diode according to said second set of performance test operating conditions.
9. The laser diode product of claim 8 , wherein the performance test comprises a burn-in procedure.
10. The laser diode product of claim 8 , wherein the accelerated life model is of the form
Median Life= A*F ( I )*exp[ Ea /( kT )]
where I represents a drive current, T represents a junction temperature, A represents a process dependent constant, E a represents an activation energy (eV), and k represents Boltzmann's constant, 8.16171*10 −5 eV per ° C.
11. The laser diode product of claim 3 , wherein F(I) is of the form
F =( I )(1/ I ) B
where B represent a drive current acceleration constant.
12. The laser diode product of claim 10 , wherein calculating a second set of performance test operating conditions further comprises:
identifying a second operating current and a second operating temperature;
determining an acceleration factor based on the accelerated life model; and
calculating the second performance test duration based on the acceleration factor and the first performance test duration.