Semiconductor laser element, testing method, and testing device
AssigneeNuvoton Technology Corporation Japan
InventorsKazumasa Nagano, Hiroki Nagai
Life of this patent
Estimating the term…
Abstract
A semiconductor laser element that includes a semiconductor layer including a waveguide formed in an intra-layer direction of the semiconductor layer and a window region formed in a front-side end face of the waveguide, has a current-laser optical output characteristic in which, at an operating temperature of 25° C.±3° C., a laser optical output has a maximum value at a first driving current value and the laser optical output is at most 20% of the maximum value at a second driving current value greater than the first driving current value, and is not damaged at the second driving current value.
Claims20
A semiconductor laser element, comprising a semiconductor layer, wherein
- the semiconductor layer includes:
- a waveguide formed in an intra-layer direction of the semiconductor layer;
- and
- a window region formed in a front-side end face of the waveguide,
- the semiconductor laser element has a current-laser optical output characteristic in which, at an operating temperature of 25° C.±3° C., a laser optical output has a maximum value at a first driving current when the first driving current is applied to the semiconductor laser element and the laser optical output is at most 20% of the maximum value at a second driving current when the second driving current greater than the first driving current is applied to the semiconductor laser element, and
- the semiconductor laser element is not damaged at the second driving current value.
A testing method for determining whether a semiconductor laser element to be tested is defective, wherein
- the semiconductor laser element to be tested includes a semiconductor layer,
- the semiconductor layer includes a waveguide formed in an intra-layer direction of the semiconductor layer and a window region formed in a front-side end face of the waveguide, and
- the testing method comprises:
- measuring a characteristic of the semiconductor laser element to be tested;
- energizing the semiconductor laser element to be tested at a second driving current value after the measuring, the second driving current value being greater than a first driving current value at which a laser optical output of the semiconductor laser element to be tested has a maximum value and being a value at which the laser optical output is at most 20% of the maximum value;
- remeasuring the characteristic of the semiconductor laser element to be tested after the energizing;
- and
- determining whether the semiconductor laser element to be tested is defective by comparing the characteristic of the semiconductor laser element to be tested which is obtained in the measuring with the characteristic of the semiconductor laser element to be tested which is obtained in the remeasuring.
Dependencies are inferred from the claim text.