Non-destructively measuring local carrier concentration and gap

Details Non-destructively measuring local carrier concentration and gap Non-destructively measuring local carrier concentration and gap

1988-03-25

1990-09-04

Rosenberger, Richard A.

Optics: measuring and testing

Of light reflection

356 30, 356432, G01N 2155, G01N 2184

Patent

active

049539833

ABSTRACT:
An apparatus and method for non-destructive measuring of local carrier concentration and bandgap in a semiconductor such as gallium arsenide or gallium aluminum arsenide. A high energy source of photons, e.g. a laser, photo injects carriers on the surface of the semiconductor causing a change in the semiconductor's surface photo reflectance. The fractional change in photo reflectance is measured for a plurality of the photon energies sufficient to identify several Franz-Keldysh peaks, and the photon energies corresponding to these peaks. This information is used to infer the local electric field strength and carrier concentration of the semiconductor as well as semiconductor's bandgap. By noting variations in these parameters throughout the bulk semiconductor, one can identify fatal fabrication flaws in the semiconductor crystal before time and money is expended to fabricate complicated semiconductor architectures in the crystal.

REFERENCES:
patent: 4211488 (1980-07-01), Kleinknecht
patent: 4652757 (1987-03-01), Carver
Glosser et al., "Comparative Responses of Electroreflectance and Photoreflectance in GaAs", SPIE Conference, Bay Point, FL. Mar. 27, 1989.
Glembocki et al., "Photoreflectance Characterization of GaAs/AlGaAs Thin Films, Heterojunctions, and Multiple Quantum Well Structures", SPIE, vol. 524, (1985), pp. 86-94.
Glembocki et al., "Photoreflectance Characterization of Interband Transitions in GaAs/AlGaAs Multiple Quantum Wells and Modulation-Doped Heterojunctions", Appl. Phys. Lett. 46(10), May 15, 1985, pp. 970-972.

Affiliated with

Also associated with

Rating

Non-destructively measuring local carrier concentration and gap does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Non-destructively measuring local carrier concentration and gap , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-destructively measuring local carrier concentration and gap will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-437761