The high vacuum cleaving facet coating passivation characteristic of laser diode

The facet coating passivation characteristic of 905nm laser diode is presented by researching catastrophic optical mirror damage (COMD) mechanism of laser diode. In the research, 905nm laser diode are cleaved in the high vacuum cleaving system, and then coated with 3.5nm and 4.5nm Si passivation film in the front and the back facet. Lastly optical films are then applied to the antireflection (AR) and high-reflectivity (HR) facets of 5% and 95% respectively in front and back facet. The test results of 905nm laser diode output power show that output power with the coated 4.5nm Si passivation film is 13% higher than coated 3.5nm Si passivation film, and 27% higher than that uncoated with passivation film. The diode uncoated passivation film is failed when input current is 25..9A, and the diode coated with 3.5nm Si passivation film is failed when input current is 27.5A, the final failed of the diode is coated 4.5nm Si passivation film. In conclusion, the method of coated 4.5nm Si passivation film in high vacuum cleaving system on the 905nm laser diode facet can effectively prevent COMD, and improve the output power.