Statistical study of the reliability of oxide-defined stripe cw lasers of (AlGa)As

Journal Article · Thu Mar 01 00:00:00 EST 1979 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.326150· OSTI ID:6398001

Ettenberg, M

In this report, we describe a statistical study of the reliability of oxide-defined stripe-contact cw injection lasers of (AlGa)As. These devices have one facet coated with Al/sub 2/O/sub 3/ and one facet coated with an Al/sub 2/O/sub 3//Si dichroic reflector; the lasers are optimized for cw low-threshold currents at room temperature, with values typically about 50 mA. Lifetests were carried out at 70 /sup 0/C ambient, in the cw mode of operation with about 5 mW output. Previous lifetests showed that the degradation rate followed a 0.95-eV activation energy so the 70 /sup 0/C environment provides a degradation acceleration factor of 190 over that at room temperature. We have found that the device failures follow a log-normal distribution, characterized by a mean time before failure of 4200 h and a standard deviation of 1.3. This corresponds to a mean time to failure (MTTF) of 10/sup 6/ h at room temperature. Failure is defined here as the inability of the device to emit 1 mW of stimulated cw output at 70 /sup 0/C, and assumes that optical feedback will be employed to adjust the laser current during operation. If a constant-current drive is envisioned, the failures for a 3-dB drop in light output also follow a log-normal distribution with a similar slope (standard deviation=1.1) and a MTTF of 2000 h at 70 /sup 0/C (500 000 h at room temperature). The failures were found to be mainly due to bulk gradual degradation and not facet or contact failure. Careful study of lasers before and after lifetest showed a significant increase in contact thermal resistance. However, this increase accounts for only a small portion of the nearly 70% increase in room-temperature cw threshold after failure at 70 /sup 0/C. After failure at 70 /sup 0/C, we also noted a degradation in the near-field and associated far-field pattern of the laser.

• Research Organization: RCA Laboratories, Princeton, New Jersey 08540
• OSTI ID: 6398001
• Journal Information: J. Appl. Phys.; (United States), Vol. 50:3
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
SEMICONDUCTOR LASERS
RELIABILITY
ALUMINIUM ARSENIDES
EXPERIMENTAL DATA
GALLIUM ARSENIDES
ISOLATED VALUES
PERFORMANCE
STATISTICS
STIMULATED EMISSION
SYSTEMS ANALYSIS
TEMPERATURE DEPENDENCE
THERMAL CONDUCTION
THRESHOLD ENERGY
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
DATA
DATA FORMS
EMISSION
ENERGY
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
GALLIUM COMPOUNDS
HEAT TRANSFER
INFORMATION
LASERS
MATHEMATICS
NUMERICAL DATA
PNICTIDES
SEMICONDUCTOR DEVICES
420300* - Engineering- Lasers- (-1989)