Lucent Technologies Inc.

Agere Systems Inc.

Agere Systems Guardian Corp.

Winfried Denk

Chunhui Xu

Vladimir Anatolyevich Aksyuk

David John Bishop

Joseph Shmulovich

Gadi Lenz

David William Tank

Semiconductor devices are imaged using two-photon absorption. The method is similar to conventional optical beam induced imaging except that the light beams used have frequencies (photon energies) insufficient to excite electrons across the semiconductor bandgap. Rather the instantaneous intensity of the lower frequency light is increased, as by using a pulsed laser source, so that electron transitions occur by two-photon absorption predominately in the localized region where the beam is focused. The result is minimal absorption during passage through the substrate and maximal absorption in the component-rich active layer where the beam is focused. This enhances imaging of fine-detail semiconductor devices. Specifically, the quadratic dependence of free carrier generation on the excitation intensity both enhances the resolution and provides a three-dimensional sectioning capability.

Method and apparatus for imaging semiconductor devices

The present invention is an inexpensive optical beam power controller for providing fast, continuous control of a linearly polarized optical beam, such as a beam from a laser. In essence, the controller comprises a birefringent plate tiltable in relation to the beam and a polarization analyzer. Alternative double pass embodiments reduce beam displacement and the required tilt angle.

Optical beam power controller using a tiltable birefringent plate

In a time-division-multiplex system, a relatively high-rate optical signal stream comprising multiple interleaved signal sequences is applied to one end of an elongated waveguide that includes multiple photodetectors disposed along the longitudinal extent of the waveguide. Probe pulses at a relatively low rate are applied to the other end of the waveguide in a synchronized fashion to cause two-photon non-linear absorption in successive respective photodetectors as each propagating probe pulse overlaps successive different signals of each sequence. In that way, electrical output signals are provided from each photodetector at the relatively low probe-pulse rate.

Optical time-division-multiplex system

A method for forming micron-sized or smaller drops of liquid, and the use of the method in fabricating micro electro mechanical and micro mechanical devices is disclosed. A micropipette is formed having an inside diameter no larger than the size of the drops to be formed. The micropipette is connected to a system capable of developing a positive and optionally negative pressure within the micropipette. The tip of the micropipette is placed in liquid. The liquid is drawn into the micropipette via capillary action or from the negative pressure developed by the system. The micropipette is then positioned to deliver liquid to an intended location on a surface. To deliver the liquid, a positive pressure is developed within the micropipette. The positive pressure forces a micron-sized or smaller drop of liquid out of the micropipette. The method can be used to form micron-sized or smaller drops of adhesive for fixing in place various structural members that form microdevices.

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Berkeley Heights, NJ, United States of America

Winfried Denk