Abstract: An optical system is disclosed which includes at least a first source of electromagnetic radiation (signal beam radiation), a device for processing the signal beam radiation, and a detector for detecting the processed signal beam radiation. The processing device functions, for example, as an amplitude modulator, a demultiplexer, or a switch, and includes a material region exhibiting a nonlinear optical response at one or more resonant wavelengths of electromagnetic radiation, as well as at least a second source of electromagnetic radiation (control beam radiation) for selectively inducing the nonlinear optical response. Significantly, the wavelength, duration and intensity of the control beam radiation are chosen to induce a resonant, nonlinear optical response, essentially free of any relatively slow component, in said material region at repetition rates higher than about 1.25.times.10.sup.4 Hz, or higher than about 3.3.times.10.sup.10 Hz, or even as high, or higher, than about 2.5.times.10.sup.11 Hz.

Abstract: A deep-UV step-and-repeat photolithography system includes a narrow-bandwidth pulsed excimer laser illumination source and an all-fused-silica lens assembly. The system is capable of line definition at the 0.5-micrometer level. One significant feature of the system is its ability to perform wafer focus tracking by simply changing the frequency of the laser.

Abstract: A new method for lithographically patterning nonplanar substrates is disclosed. In accordance with this method, a nonplanar substrate surface is patterned by initially substantially conformably coating the surface with a resist. Conformality is achieved by depositing the resist either from the vapor phase or from a mist. In addition, the motions of the constituents of the vapor or mist should be sufficiently random so that the angular flux distribution at any point on the nonplanar substrate surface to be coated is substantially identical to that at any other point to be coated.

Abstract: A new CMOS device which avoids latchup while achieving a spacing between the n-channel and p-channel FETs of the device smaller than 10 .mu.m, as well as a method for fabricating the choice, is disclosed.The inventive device, which is formed in a substrate comprising a relatively heavily doped bulk region supporting a relatively thin, moderately doped layer, includes a polysilicon-filled trench extending through a portion of the layer, between the n- and p-channel FETs of the device. The inventive device also includes a relatively heavily doped region extending from a bottom of the trench to the bulk region. The polysilicon-filled trench, in combination with both the relatively heavily doped region and bulk region, prevents latchup.

Abstract: An optical system, e.g., an optical fiber communication system or an optical mass storage device, which includes a linearly birefringent polarization rotator useful in an optical isolator or optical circulator, is disclosed. The rotator, which compensates for the effects of linear birefringence and is substantially antireciprocal, includes two or more material regions which are capable of subjecting incident light to elliptic birefringences. However, the sign and/or magnitude of the linear, or the sign and/or magnitude of the circular, components of the elliptic birefringences differ from region to region. Moreover, the length of each region, except the first or last region, is substantially equal to one-half the birefringent period of the region. The length of the first or last region, by contrast, is substantially equal to one-quarter the birefringent period of the region.

Abstract: A new SOI device which permits both the kink effect to be avoided and threshold voltage to be regulated, as well as a new method for fabricating SOI ICs, is disclosed. The new device included an electrically conductive pathway extending from the active volume and terminating in a non-active region of the substrate of the device. A back-gate bias is communicated to, and kink-inducing charges are conducted away from, the active volume through the conductive pathway. The new fabrication methd permits SOI ICs to be fabricated using available circuit designs and pattern delineating apparatus, e.g., IC mask sets. This method involves the formation of a precursor substrate surface which includes islands of insulating material, each of which is encircled by a crystallization seeding area of substantially single crystal semiconductor material. The boundaries of the islands are defined with a first pattern delineating device, e.g.

Abstract: The invention involves the finding that the congruent composition of any complex oxide is non-stoichiometric.

Abstract: Optical communication and sensing systems are disclosed which operate at long wavelengths, i.e., wavelengths greater than about 2 .mu.m, but less than or equal to about 11 .mu.m. Each of these systems includes an optical fiber having material, such as a metal halide glass, which is substantially transparent to long wavelength electromagnetic radiation. These optical fibers exhibit reduced microdeformation and macrobending losses, as well as low total dispersions, at the long wavelengths. In contrast to currently held beliefs, this is achieved by using fiber designs involving relatively small relative refractive index differences, which are readily manufacturable and which avoid undesirable crystallization at core-cladding interfaces.

Abstract: Threshold electric fields required to achieve high speed matrix addressing of selected cells in a bistable nematic liquid crystal storage display are reduced by employing a short duration, priming pulse signal in accordance with the principles of the invention. The short priming pulse signal applied to a selected cell modifies the binding energy for disclinations attached to sites of orientational discontinuity, thereby changing the threshold field required for electrical switching between bistable states. Threshold reduction also depends on the AC frequency and duration of a writing pulse signal applied to the selected cell subsequent to the priming pulse signal.

Abstract: The invention is a nonlinear or bistable optical device having a low switching energy. The invention uses a means responsive to light for generating a photocurrent, a structure having a semiconductor quantum well region, and means responsive to the photocurrent for electrically controlling an optical absorption of the semiconductor quantum well region. The optical absorption of the semiconductor quantum well region varies in response to variations in the photocurrent. A photodiode or phototransistor may be used as the means responsive to light, and may be made integral with the structure having the semiconductor quantum well region. An array of devices may be fabricated on a single chip for parallel logic processing.

Abstract: An integrated optical device is disclosed which includes an integral photodetector exhibiting picosecond response times and quantum efficiences greater than about 30 percent. The photodetector includes a region of substantially amorphous semiconductor material interposed between two electrodes, with the electrode spacing being comparable to the average electron trapping length in the material between the electrodes. Preferably, at least one of the electrodes is a microstrip transmission line.

Abstract: A new method for fabricating a device, such as a semiconductor device, is disclosed. The method includes the step of patterning a substrate with a trilevel resist containing a spin-deposited substitute for the conventional central, silicon dioxide region. This substitute includes an organosilicon glass resin in combination with metal-and-oxygen containing material. The inventive method prevents the losses of linewidth control, and avoids the pattern degradation due to undesirably many pinholes, of previous such methods.

Abstract: A method for partially or fully restoring the lost capacities of nickel batteries, as well as the batteries produced by this method, is disclosed.In accordance with the inventive method, a nickel battery is cycled at least 10 times, with each cycle including a discharging step during which the capacity achieved at the end of the previous cycle is reduced by at least 5 percent, and a charging step. The charging rate employed during the charging step is greater than about C/10 per hour. Moreover, while the ratio of the amount of charge delivered to the battery during the charging step of each cycle to the amount of charge withdrawn from the battery during the previous cycle is greater than one, this ratio is chosen so that the temperature of the electrolyte of the battery does not exceed about 30 degrees Centigrade.

Abstract: The invention involves new etch monitoring and thickness measurement techniques which are more accurate than previous techniques. In accordance with the invention, the etch depth of a substrate region undergoing etching is monitored, or the thickness of the region is measured, by impinging the region with light and detecting the intensity of the reflected light. In contrast to the previous techniques, the incident light is chosen so that a substrate region underlying, and/or a patterned substrate region overlying the substrate region of interest is substantially opaque to the incident light, which precludes the formation of signals unrelated to etch depth or thickness.

Abstract: An optical system, e.g., an optical fiber communication system or an optical mass storage device, which includes a linearly birefringent polarization rotator useful in an optical isolator or optical circulator, is disclosed. The rotator, which compensates for the effects of linear birefringence and is substantially antireciprocal, includes two or more material regions which are capable of subjecting incident light to elliptic birefringences. However, the sign and/or magnitude of the linear, or the sign and/or magnitude of the circular, components of the elliptic birefringences differ from region to region. Moreover, the length of each region, except the first or last region, is substantially equal to one-half the birefringent period of the region. The length of the first or last region, by contrast, is substantially equal to one-quarter the birefringent period of the region.

Abstract: Photosensitive bodies that are sensitive to ultraviolet radiation and that exhibit excellent contrast are formed from base soluble polymers such as poly(methyl methacrylate-co-methacrylic acid) physically mixed with base insoluble materials such as o,o'-dinitrobenzyl esters. The base insoluble esters decompose upon irradiation to form base soluble entities in the irradiated regions. These irradiated portions are then soluble in basic solutions that are used to develop the desired image.

Abstract: A new method for fabricating CMOS devices, as well as the resulting devices, is disclosed. The method involves incorporating dopants into a semiconductor substrate through a region of the substrate surface, and diffusing the implanted dopants into the substrate to form a tub. Prior to the diffusion step, a trench is formed in, and extending beneath, the surface which partially or completely encircles the region. The trench serves to prevent the formation, or reduce the size, of a relatively low dopant concentration region, which would otherwise lead to undesirable leakage currents in the completed CMOS device, and prevents latchup.

Abstract: A new CMOS device which avoids latchup while achieving a spacing between the n-channel and p-channel FETs of the device smaller than 10 .mu.m, as well as a method for fabricating the choice, is disclosed. The inventive device, which is formed in a substrate comprising a relatively heavily doped bulk region supporting a relatively thin, moderately doped layer, includes a polysilicon-filled trench extending through a portion of the layer, between the n- and p-channel FETs of the device. The inventive device also includes a relatively heavily doped region extending from a bottom of the trench to the bulk region. The polysilicon-filled trench, in combination with both the relatively heavily doped region and bulk region, prevents latchup.

Abstract: A new CMOS device which avoids latchup while achieving a spacing between the n-channel and p-channel FETs of the device smaller than 10 .mu.m, as well as a method for fabricating the device, is disclosed.The inventive CMOS device includes a latchup-preventing, polysilicon-filled trench formed in the semiconductor substrate between the n- and p-channel FETs of the device. The polysilicon-filled trench is essentially free of crack-inducing voids, and achieves a width less than 10 .mu.m, because the angle between the trench sidewall and a perpendicular drawn to the substrate surface is greater than, or equal to, about 5 degrees but less than about 10 degrees. Also, a thickness of the polysilicon deposited into the trench is greater than half the width of the trench.

Abstract: The bandwidth required for a regularly occurring signal such as a television signal, as received from a signal source can be substantially reduced by not transmitting each and every one of the horizontal scan lines. Rather, firstly, one or more selected lines may be transmitted and, secondly, instead of transmitting the remaining, unselected lines, a signal representing a predetermined arithmetic difference among predetermined ones of the scan lines may be transmitted.