Near field optical probe for critical dimension measurements

Patent · Thu Dec 31 23:00:00 EST 1998

OSTI ID:872293

Stallard, Brian R ^[1]; Kaushik, Sumanth ^[2]

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1. Albuquerque, NM
2. Cambridge, MA

A resonant planar optical waveguide probe for measuring critical dimensions on an object in the range of 100 nm and below. The optical waveguide includes a central resonant cavity flanked by Bragg reflector layers with input and output means at either end. Light is supplied by a narrow bandwidth laser source. Light resonating in the cavity creates an evanescent electrical field. The object with the structures to be measured is translated past the resonant cavity. The refractive index contrasts presented by the structures perturb the field and cause variations in the intensity of the light in the cavity. The topography of the structures is determined from these variations.

• Research Organization: SANDIA CORP
• DOE Contract Number: AC04-94AL85000
• Assignee: Sandia Corporation (Albuquerque, NM)
• Patent Number(s): US 5905573
• OSTI ID: 872293
• Country of Publication: United States
• Language: English

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100
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evanescent
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flanked
index
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intensity
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near
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planar
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refractive
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resonating
source
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translated
variations
waveguide