Abstract: Certain embodiments disclosed herein are directed to devices for cooling. In certain examples, a thermoelectric device comprising a substrate and a superlattice coupled to the substrate is disclosed. In some examples, the superlattice includes a first semi-conducting material and a second semi-conducting material coupled to the first semi-conducting material to provide an interface between the first and second semi-conducting materials.

Abstract: A capacitor based sensor for angular position detection having two fixed plates arranged at an angle and a semicircular rotating plate in between. The sensor can determine any angular position in the full 0-360 degrees range. The sensor may be temperature compensated, and integrated with electronics such that sensor module only has two electrical leads, one for input power and one for input/output digital data. A method for converting capacitance measurements to an angle is also disclosed.

Abstract: Subterranean devices are provided that are configured or designed for high temperature downhole use. The downhole devices comprise an electronic device configured or designed for downhole use in the well and a heat dissipation system. The heat dissipation may include one or more active coolers and a micro-particulate radiation improving coating applied to the active cooler.

Abstract: A capacitor based sensor for angular position detection having two fixed plates arranged at an angle and a semicircular rotating plate in between. The sensor can determine any angular position in the full 0-360 degrees range. The sensor may be temperature compensated, and integrated with electronics such that sensor module only has two electrical leads, one for input power and one for input/output digital data. A method for converting capacitance measurements to an angle is also disclosed.

Abstract: Certain embodiments disclosed herein are directed to devices for cooling. In certain examples, a thermoelectric device comprising a substrate and a superlattice coupled to the substrate is disclosed. In some examples, the superlattice includes a first semi-conducting material and a second semi-conducting material coupled to the first semi-conducting material to provide an interface between the first and second semi-conducting materials.

Abstract: Subterranean devices are provided that are configured or designed for high temperature downhole use. The downhole devices comprise an electronic device configured or designed for downhole use in the well and a heat dissipation system. The heat dissipation may include one or more active coolers and a micro-particulate radiation improving coating applied to the active cooler.

Abstract: A downhole tool, configured to be suspended in a borehole traversing an earth formation, includes a downhole data acquisition system placed in the tool body and electrically connected to an electric power generator at the formation surface. The downhole data acquisition system includes a sensor for detecting local conditions in the borehole, and a transducer for transducing the voltage of an input signal from high to low or low to high. The transducer having a gallium nitride or silicon carbide based discrete semiconductor device.

Abstract: Methods and apparatus for creating a velocity profile of a formation surrounding a borehole by checkshot measurements while moving the tool along the borehole. A conveyance and a sensor section are configured to move the sensor section in the borehole. At least one receiver is configured to detect signals generated at or near the surface while the sensor section is moving in the borehole.

Abstract: The principles described herein relate to methods for soldering electrode terminals, pins or lead-frames of commercial electric components for high temperature reliability. In one embodiment, prior to soldering the electric components, a pre-plated solder layer is removed from the lead frame or pins, and nickel and/or gold films are formed with electroless plating. The removal of the pre-plated solder layer avoids excess pre-plated Sn with high-Pb solder that lowers the melting point to between 180° C. and 220° C. and weakens solder joints. The nickel layer formed with an electroless plating acts as a barrier to the interdiffusion of tin from solder with copper of the lead frame material, which may otherwise occur at high temperatures. Interdiffusion forms an intermetallic compound layer of copper and tin and degrades solder joint strength. The novel soldering processes improve high temperature reliability of solder joints and extend electronics life-time.

Abstract: A downhole tool having at least one semiconductor device, including: a die; a bonding pad which is attached to the surface of the die; a bonding wire which is attached to the bonding pad; a bonding point which is formed on the bonding pad for connecting the bonding wire to the bonding pad; an encapsulating resin encapsulating the die and being provided with a cavity such that a connecting portion of the bonding point and the bonding pad is exposed out of the resin in the cavity; and a lid on the encapsulating resin to cover the cavity.

Abstract: Certain embodiments disclosed herein are directed to devices for cooling. In certain examples, a thermoelectric device comprising a substrate and a superlattice coupled to the substrate is disclosed. In some examples, the superlattice includes a first semi-conducting material and a second semi-conducting material coupled to the first semi-conducting material to provide an interface between the first and second semi-conducting materials.

Abstract: Methods and apparatus for creating a velocity profile of a formation surrounding a borehole by checkshot measurements while moving the tool along the borehole. A conveyance and a sensor section are configured to move the sensor section in the borehole. At least one receiver is configured to detect signals generated at or near the surface while the sensor section is moving in the borehole.

Abstract: Methods of manufacturing printed circuit board assemblies include placing a semiconductor chip having a plurality of lead terminals on a board formed with a plurality of solder lands at its surface such that each of the plurality of lead terminals is in touch with a corresponding one of the solder lands; supplying a solder material on the plurality of lead terminal s and the plurality of solder lands; supplying a flux including mono salt of adipic acid and alkyl secondary amine; and locally heating the plurality of lead terminals such that the solder material and the flux are melted to join together the lead terminals and the solder lands.

Abstract: A downhole tool, configured to be suspended in a borehole traversing an earth formation, includes a downhole data acquisition system placed in the tool body and electrically connected to an electric power generator at the formation surface. The downhole data acquisition system includes a sensor for detecting local conditions in the borehole, and a transducer for transducing the voltage of an input signal from high to low or low to high. The transducer having a gallium nitride or silicon carbide based discrete semiconductor device.

Abstract: The principles described herein relate to methods for soldering electrode terminals, pins or lead-frames of commercial electric components for high temperature reliability. In one embodiment, prior to soldering the electric components, a pre-plated solder layer is removed from the lead frame or pins, and nickel and/or gold films are formed with electroless plating. The removal of the pre-plated solder layer avoids excess pre-plated Sn with high-Pb solder that lowers the melting point to between 180° C. and 220° C. and weakens solder joints. The nickel layer formed with an electroless plating acts as a barrier to the interdiffusion of tin from solder with copper of the lead frame material, which may otherwise occur at high temperatures. Interdiffusion forms an intermetallic compound layer of copper and tin and degrades solder joint strength. The novel soldering processes improve high temperature reliability of solder joints and extend electronics life-time.

Abstract: A borehole logging tool system includes a surface system, a logging array, and a logging cable providing power supply and data paths connecting the logging array to the surface system, wherein the logging array includes a series of discrete sondes connected together. The sondes in the logging array, for example a borehole seismic logging array, are connected to their neighbours by means of lengths of logging cable. Such cable can be the same as that connecting the logging array to the surface system. The logging array can also include a master controller module which communicates with the surface system and which includes a first controller module which connects to the surface system and a second controller which controls operation of the sondes in the logging array independently of any other borehole logging tools connected to the surface system.

Abstract: Apparatus and method for investigating a borehole casing. The preferred apparatus generally comprises: a housing which is connected to a cable; sets of electrodes, each set being axially spaced from another set, with the electrodes in each set being circumferentially spaced at an axial depth; a positioning device provided in the housing for bringing the electrodes into contact with the casing; a measuring circuit provided inside of the housing and electrically connected to the electrodes for measuring at least the potential difference of the casing between the electrode locations, wherein the potential difference information is amplified by the measuring circuit, and the amplified information is transmitted through the cable for processing; and a control circuit provided in the housing for controlling the operation of the positioning device and the measuring circuit.