Abstract: The invention relates generally to optoelectronic pnpn devices and more particularly to a layer structure suitable for fast electrical complete turn-off of such devices and to a method for efficient and fast operation of such devices and differential pairs of such devices. The devices have four layers and three junctions, and the invention provides for complete depletion of both center layers. The differential pair of pnpn devices also provides a very sensitive optical receiver which combines a very high cycle frequency with a very high optical sensitivity.

Abstract: Disclosed is a photodetector with a multilayer filter. A light-receiving substrate is mounted on a recessed portion of a ceramic stem. An electrode pad is formed on a P-type layer of the light-receiving substrate while another electrode pad is formed on an N-type layer of the light-receiving substrate. An optical multilayer filter is formed on the light-receiving substrate except the regions of the electrode pads. Further, an epoxy transparent resin is poured into the recessed portion of the stem and then cured, so that a resin portion to cover the light-receiving substrate is formed. The optical multilayer filter is formed of amorphous low refractive index films made of SiC.sub.2 and amorphous high refractive index films made of TiO.sub.2. The amorphous high and low refractive index films are alternately stacked.

Abstract: An optoelectronic device based on a conduction constriction through which charge carriers pass ballistically. The constriction has a cross-sectional area of 2 square microns or less and a thickness D and is made of doped semiconductor material with a carrier mobility .mu.. The thickness D is selected to be near to a characteristic path length D.sub.mes defined by D.sup.2.sub.mes =(h/2e)*.mu. where h is Planck's constant and e the elementary charge. The device can be used as a heterodyne radiation detector for detecting radiation in the frequency range between 3 GHz and 3 THz and is capable of detecting signals with a power of less than 10.sup.-14 watts in room temperature operation. The device can also be operated as the front end of a spectrometer. Other applications of the device include use as a high frequency AC current source or oscillator for microelectronics, for instance in the 100 to 500 GHz range.

Abstract: A photoconductor has an active layer of gallium nitride having approximately 10.sup.15 to 5.times.10.sup.15 net donor sites per cubic centimeter and is sensitive to UV radiation. This photoconductor has at least one of a sheet resistance in the approximate range of 10.sup.4 to 5.times.10.sup.6 ohms/unit area and a relatively low level of photoluminescence in the range from about 430-450 nm when excited with light of energy higher than the bandgap energy of 3.4 eV. These criteria tend to define similar semiconductor materials which can form the active layer of an ultraviolet (UV) photodetector having the improved characteristics of a relatively low dark resistance, high sensitivity over at least a range of UV radiation intensity, and decreasing gain with increasing UV radiation.

Abstract: Si-based photodetectors according to the invention can have high speed (e.g.,.gtoreq.1 Gb/s) and high efficiency (e.g.,>20%). The detectors include a relatively thin (e.g.,<0.5.alpha..sup.-1, where .alpha..sup.-1 is the absorption length in Si of the relevant radiation) crystalline Si layer on a dielectric (typically SiO.sub.2) layer, with appropriate contacts on the Si layer. Significantly, the surface of the Si layer is textured such that the radiation that is incident on the surface and transmitted into the Si layer has substantially random direction. The randomization of the propagation direction results in substantial trapping of the radiation in the Si layer, with attendant increased effective propagation length in the Si. Detectors according to the invention advantageously are integrated with the associated circuitry on a Si chip, typically forming an array of detectors.

Abstract: A coplanar photodiode construction is disclosed having particular utility in X-ray detection applications in which alternating P-doped and N-doped regions, separated by undoped material, are located in relatively shallow depth under and along the surface between the photodiode and an associated X-ray scintillating crystal.

Abstract: In a photovoltaic device, when an internal electric field in a photoelectric conversion layer becomes non-uniform in the surface direction of the layer for a reason such as the interface between a transparent conductive film and the photoelectric conversion layer being formed in an irregular shape, the internal electric field in the photoelectric conversion layer is made uniform by (1) making the thickness of an intrinsic layer inside the photoelectric conversion layer in portions of the photoelectric conversion layer where the internal electric field becomes weak smaller than that in the other portions, (2) providing regions where conductivity is high and activation energy is low in the photoelectric conversion layer in the said portions, or (3) containing a ferroelectric material in a portion of the intrinsic layer inside the photoelectric conversion layer.

Abstract: A photoelectric converting device comprises a first semiconductor area of a first conductivity type, a second semiconductor area of a second conductivity type, and a third semiconductor area of the first conductivity type. A charge is photoelectrically excited by light incident on the second semiconductor area, and is derived from the first semiconductor area after amplification.A fourth semiconductor area of the first conductivity type is formed in contact with the second semiconductor area and so positioned corresponding to the third semiconductor area. During operation of the device, a depletion layer extending from the interface between the third and fourth semiconductor areas reaches a depletion layer extending from the interface of the third and second semiconductor areas.

Abstract: A miniaturized electronic imaging chip has stratified layers wherein a base silicon layer has a peripheral edge defining an area and a thickness which allows passage therethrough of most UV, visible and IR light. A pixel layer is formed on the back side of this first silicon layer. At least one interconnect layer is bonded to the pixel layer. Electric leads are bump bonded to the bonding pads on the outermost interconnect layer and extend away from it within the area for attachment to means for sensing electrical signals generated by an image projected onto the pixel layer through the silicon layer. Preferably, the leads are perpendicular to the chip.

Abstract: In an opto-electronic integrated circuit of the present invention, in a first surface region of a semiconductor substrate, a pin-type photodiode is constituted on the basis of a photodiode layer formed on a first transistor layer. In a second surface region of the semiconductor substrate, a heterojunction bipolar transistor is constituted on the basis of only a second transistor layer separated form the first transistor layer. Since a plurality of heterojunction bipolar transistors are normally integrated for one pin-type photodiode, the thickness of the heterojunction bipolar transistors larger in number than the pin-type photodiode is set regardless of the thickness of the pin-type photodiode. The thickness of a high-resistance layer in the pin-type photodiode is set with an increased degree of freedom.

Abstract: A photo sensor comprises a semiconductor substrate, a bipolar photo transistor having an emitter region, a base region and a collector region which is formed in the surface region of the semiconductor substrate, a silicon dioxide formed on the bipolar phototransistor, and a film having a smaller diffusion coefficient of hydrogen than the silicon dioxide formed all over the silicon dioxide.

Abstract: A light-receiving semiconductor device with improved light sensitivity. On a semiconductor substrate of a first conductivity type is formed a plurality of buried layers of a second conductivity type divided by a narrow dividing region. A surface semiconductor layer of the first conductivity type covers the buried layers and the substrate. A connecting semiconductor region of the second conductivity type extends from each of the plurality of the buried layers to the surface of the surface semiconductor layer. An anti-light-reflecting film formed on the surface of the surface semiconductor layer covers a region above the dividing region as well as above the plurality of buried layers. Each of the plurality of buried layers forms a light responsive element with the substrate.

Abstract: In a optoelectronic integrated circuit, a pin-type light receiving device and an electronic circuit device are electrically connected to each other and monolithically integrated on a semiconductor substrate. In the pin-type light receiving device, an n-type semiconductor layer, an i-type semiconductor layer, and a p-type semiconductor layer are sequentially formed on the semiconductor substrate and sequentially formed into mesa shapes. The first mesa is constituted by the p-type semiconductor layer, and the second mesa is constituted by the i-type semiconductor layer. The boundary surface between the first and second mesas is formed to match the junction surface between the p-type semiconductor layer and the i-type semiconductor layer. The diameter of the first mesa is formed smaller than that of the second mesa.

Abstract: A planar photosensitive device, such as an array of APDs, includes a planar block of n type semiconductor material having a plurality of p type wells in the block surrounded by a foundation of n type semiconductor material. Each p type well corresponds to an APD pixel and is disposed so as to respectively adjoin a first surface of the block and such that a respective p-n junction is formed between the p type material in the well and the n type material foundation. Each APD pixel further comprises depletion layer profile modification means such that the peak surface electric field of the p-n junction in each well is substantially less than the bulk electric field of the same p-n junction.

Abstract: A photodiode structure for the detection of radiation comprises a semiconductor base layer of p-type conductivity with a high doping density, an epitaxial layer of p-type conductivity with a relatively low doping density, areas of n-type conductivity and oxide layers covering the areas of n-type conductivity. The oxide layers comprise doping impurities of the same conductivity type as the areas below them. The doping density in the areas of n-type conductivity decrease towards the junction with the epitaxial layer. Due to this decrease in doping density, an electric field gradient is produced which guides the charge carriers to the junction. The generation of a field gradient and the creation of a surface charge result in an improved quantum efficiency. The invention is preferably used in photodiode arrays.

Abstract: An optical semiconductor includes a photo diode integrated with a transistor built on first and second epitaxial layers grown of intrinsic material on a lightly doped substrate. A separating area divides the optical semiconductor into first and second isolated islands. The separating area is made up of a three separating areas, united end to end to form a single separating area. The first separating area is diffused at least upward from an interface between the substrate and the first epitaxial area. The second separating area is diffused both downward and upward from an interface between the first and second epitaxial layers. The third separating area is diffused downward from the surface of the second epitaxial layer into the substrate. The photo diode is formed in the first island area, and the transistor is formed in the second island area. An offsetting layer in the surface of the substrate, at least below the first island, is counterdoped to expand the depth of the depletion layer of the photo diode.

Abstract: An integrated circuit includes a photo diode having a first electrically isolated portion of an epitaxial layer of a first conductivity type, a first semiconductor layer of a second conductivity type disposed therein, a second semiconductor layer of the first conductivity type disposed in the first semiconductor layer, and a third semiconductor layer of the second conductivity type disposed in the second semiconductor layer.

Abstract: A semiconductor device consisting of epitaxial material is provided with at least one monoatomic layer of doping atoms, i.e. with a layer which is just one atom thick. A preferred device is a bipolar transistor in which case the Dirac-delta doped p-type layer 38 is directly between n-type collector and emitter layers (32, 33). The bipolar transistor described herein has an extremely low base width and is capable of operating at high frequencies.

Abstract: A solar cell or photo diode has an n-type semiconductor layer and a p-type semiconductor layer which form a pn-junction at the metallurgical interface of the layers. A thin sheet of undoped semiconductor is located at the interface or the lower doped layer. The sheet has less recombination centers than its adjacent regions and prevents cross-doping of donors and acceptors from the n- and p-side by cross-diffusion to increase the open circuit voltage and fill-factor of the solar cells or photo diode.

Abstract: A semiconductor light wave detector which has a first layer of a highly doped n-type semiconducting substrate, a second layer of a highly doped n-type semiconducting material, a third layer of a distinct intrinsic semiconducting material and a fourth layer of a highly doped n-type semiconducting material similar to the second layer. First and second electrical connections are provided to the fourth layer and to at least one of the first and second layers. A plurality of pairs of Dirac-delta doped monoatomic layers are in the third layer, with the first monoatomic layer of each pair being a layer of donors and with the second monoatomic layer of each pair being acceptors spaced from the donor layer and positioned on the side thereof facing the fourth layer.

Abstract: A TFT device has an insulation substrate, a semiconductor layer formed on the insulation substrate, a pair of opposed electrodes formed on the semiconductor layer, and a gate electrode formed on the semiconductor layer with an insulation film interposed therebetween, wherein a region doped with at least one type of impurity selected from atoms belonging to the V group of the periodic table is formed in the semiconductor layer at the vicinity of the interface between the semiconductor layer and the insulation layer.

Abstract: A phototransistor includes a monocrystalline semiconductor substrate of a first conductivity type, a crystalline semiconductor layer of a second conductivity type formed from a surface of the semiconductor substrate to a predetermined depth, a substantially intrinsic amorphous semiconductor layer formed on the crystalline semiconductor layer, and an amorphous semiconductor layer of the first conductivity type formed on the intrinsic amorphous semiconductor layer.

Abstract: An optically bistable semiconductor device which has a doped or undoped gallium arsenide substrate and a series of alternating n-type and p-type Dirac-delta doped monoatomic layers formed on the substrate. Each Dirac-delta doped monoatomic layer is separated from the next adjacent Dirac-delta doped monoatomic layer by a layer of pure, undoped intrinsic semiconductor material such as gallium arsenide.

Abstract: In the case of a photocell based on gallium arsenide or indium phosphide, a layer of amorphous, hydrogenous carbon (a-C:H) having a thickness of .ltoreq.0.1 .mu.m and a specific electrical resistance of .gtoreq.10.sup.6 .OMEGA..cm is placed on a layer of p-doped gallium arsenide (GaAs) or indium phosphide (InP).

Abstract: A surface electron barrier region is formed on a semiconductor membrane device by a single step laser process which produces a sharp doping profile in a surface region above the light penetration depth. Enhanced quantum efficiency is observed, and by selectively forming barrier layers of differing depth, a CCD device architecture for two-color sensitivity is achieved. The barrier layer results in enhanced membrane-type and radiation hardened bipolar and CMOS devices.

Abstract: A buried P-N junction photodiode is obtained in LinBiCMOS process with junctions formed between N+DUF diffused region and both first P-EPI layer and second P-EPI layer. Contact to N+DUF diffused region is made by a small area deep N+collector diffusion or N well diffusion. This novel buried-junction photodiode can be used for several types of unique photodetector structures including: single photodiode with low surface leakage current, multi-junction photodiodes for incident light spectral distribution information and higher efficiency visible response photodetectors. The disclosed structures are compatible with bipolar and CMOS processes for providing on-chip integration of optical photodetectors with Linear ASIC standard cells and other circuit functions.

Abstract: Lubricating oil composition which comprises: lubricating base oil,(A) at least one organophosphorus compound represented by the general formula (I), (II), (III), (IV), (V), (VI), (VII) or (VIII)and(B) at least one organomolybdenum compound selected from the group consisting of molybdenum oxysulfide alkylphosphorodithioates and molybdenum oxysulfide alkyldithiocarbamates.The lubricating oil composition is excellent in antiwear properties, anti-seizure properties, and corrosion resistance, and is suitable for gear oils, and bearing oils, also for internal combustion engine oils and automatic transmission fluids, and further for hydraulic fluids, metal working fluids.