Method of manufacturing high-quality semiconductor light-emitting devices
AssigneeAmerican Telephone and Telegraph Company, AT&T Bell Laboratories
InventorsDavid A. Ackerman, Renato M. Camarda, Robert L. Hartman, Magaly Spector
Life of this patent
Estimating the term…
Abstract
A nondestructive method is proposed for measuring stripe dimensions in order to grade light-emitting structures such as lasers. The width of the near-field emission parallel to the stripe is measured while the laser is operating below threshold. This measurement is correlated with the actual stripe width and with the possibility of kinks developing in the light output. The width of the far-field emission perpendicular to the junction plane can also be measured, and the product of the two widths can be correlated with the stripe area and the possibility of kinks in the laser output.
Claims8
A method of grading a light-emitting stripe geometry structure having a certain stripe width comprising the steps of:
- applying an excitation to the structure so as to produce a spontaneous light emission having a near-field intensity which is a function of position across the stripe;
- measuring said intensity of the near-field of the spontaneous emission of the light-emitting structure across the stripe to establish a near-field intensity profile having a characteristic width at various intensities;
- determining a width of the measured intensity profile;
- and
- grading said structure according to whether the width of the intensity profile is above or below a predetermined cut-off value.
Dependencies are inferred from the claim text.