Abstract: An electronic device comprising a generator for generating a stream of charge carriers. The generator comprises a bipolar transistor having an emitter region, a collector region and a base region oriented between the emitter region and the collector region, and a controller for controlling exposure of the bipolar transistor to a voltage in excess of its open base breakdown voltage (BVCEO) such that the emitter region generates the stream of charge carriers from a first area being smaller than the emitter region surface area. The electronic device may further comprise a material arranged to receive the stream of charge carriers for triggering a change in a property of said material, the emitter region being arranged between the base region and the material.

Abstract: A tunnel transistor includes source diffusion (4) of opposite conductivity type to a drain diffusion (6) so that a depletion layer is formed between source and drain diffusions in a lower doped region (8). An insulated gate (16) controls the position and thickness of the depletion layer. The device includes a quantum well formed in accumulation layer (20) which is made of a different material to the lower layer (2) and cap layer (22).

Abstract: The present invention discloses an electronic device comprising a generator for generating a stream (125) of charge carriers. The generator comprises a bipolar transistor (100) having an emitter region (120), a collector region (160) and a base region (140) oriented between the emitter region (120) and the collector region (160), and a controller for controlling exposure of the bipolar transistor (100) to a voltage in excess of its open base breakdown voltage (BVCEO) such that the emitter region (120) generates the stream (125) of charge carriers from a first area being smaller than the emitter region surface area. The electronic device may further comprise a material (410) arranged to receive the stream of charge carriers for triggering a change in a property of said material, the emitter region (120) being arranged between the base region (140) and the material (410).

Abstract: A semiconductor device includes a semiconductor region having a pn junction and a field shaping region located adjacent the pn junction to increase the reverse breakdown voltage of the device. The field shaping region is coupled via capacitive voltage coupling regions to substantially the same voltages as are applied to the pn junction. When a reverse voltage is applied across the pn junction and the device is non-conducting, a capacitive electric field is present in a part of the field shaping region which extends beyond a limit of the pn junction depletion region which would exist in the absence of the field shaping region. The electric field in the field shaping region inducing a stretched electric field limited to a correspondingly stretched pn junction depletion region in the semiconductor region.

Abstract: A tunnel transistor includes source diffusion (4) of opposite conductivity type to a drain diffusion (6) so that a depletion layer is formed between source and drain diffusions in a lower doped region (8). An insulated gate (16) controls the position and thickness of the depletion layer. The device includes a quantum well formed in accumulation layer (20) which is made of a different material to the lower layer (2) and cap layer (22).

Abstract: A semiconductor device includes a semiconductor region having a pn junction and a field shaping region located adjacent the pn junction to increase the reverse breakdown voltage of the device. The field shaping region is coupled via capacitive voltage coupling regions to substantially the same voltages as are applied to the pn junction. When a reverse voltage is applied across the pn junction and the device is non-conducting, a capacitive electric field is present in a part of the field shaping region which extends beyond a limit of the pn junction depletion region which would exist in the absence of the field shaping region. The electric field in the field shaping region inducing a stretched electric field limited to a correspondingly stretched pn junction depletion region in the semiconductor region.

Abstract: A thermally programmable memory has a programmable element (20) of a thermally programmable resistance preferably of phase change material, material and a blown antifuse (80) located adjacent to the programmable material. Such a blown antifuse has a dielectric layer (100) surrounded by conductive layers (90, 110) to enable a brief high voltage to be applied across the dielectric to blow a small hole in the dielectric during manufacture to form a small conductive path which can be used as a tiny electrical heater for programming the material. Due to the current confinement by the hole, the volume of the material that must be heated in order to switch to a highly-resistive state is very small. As a result the programming power can be low.

Abstract: A BiCMOS-compatible JFET device comprising source and drain regions (17, 18) which are formed in the same process as that used to form the emitter out-diffusion or a vertical bipolar device, wherein the semiconductor layer which forms the emitter cap in the bipolar device forms the channel (16) of the JFET device and the layer of material (i.e. the base epi-stack) which forms the intrinsic base region of the bipolar device forms the intrinsic gate region (14) of the JFET device. As a result, the integration of the JFET device into a standard BiCMOS process can be achieved without the need for any additional masking or other processing steps.

Abstract: A semiconductor device, for example a diode (200), having a pn junction (101) has an insulating material field shaping region (201) adjacent, and possibly bridging, the pn junction. The field shaping region (201) preferably has a high dielectric constant and is coupled via capacitive voltage coupling regions (204,205) to substantially the same voltages as are applied to the pn junction. When a reverse voltage is applied across the pn junction (101) and the device is non-conducting, a capacitive electric field, is present in a part of the field shaping region which extends beyond a limit of the pn junction depletion region which would exist in the absence of the field shaping region (201), the electric field in the field shaping region inducing a stretched electric field limited to a correspondingly stretched pn junction depletion region (208,209) and an increased reverse breakdown voltage of the device.

Abstract: A thermally programmable memory has a programmable element (20) of a thermally programmable resistance preferably of phase change material, material and a blown antifuse (80) located adjacent to the programmable material. Such a blown antifuse has a dielectric layer (100) surrounded by conductive layers (90, 110) to enable a brief high voltage to be applied across the dielectric to blow a small hole in the dielectric during manufacture to form a small conductive path which can be used as a tiny electrical heater for programming the material. Due to the current confinement by the hole, the volume of the material that must be heated in order to switch to a highly-resistive state is very small. As a result the programming power can be low.

Abstract: The invention relates to a trench bipolar transistor structure, having a base 7, emitter 9 and collector 4, the latter being divided into a higher doped region 3 and a lower doped drift region 5. An insulated gate 11 is provided to deplete the drift region 5 when the transistor is switched off. The gate 11 and/or doping levels in the drift region 5 are arranged to provide a substantially uniform electric field in the drift region in this state, to minimise breakdown. In particular, the gate 11 may be seminsulating and a voltage applied along the gate between connections 21,23.

Abstract: A field effect transistor semiconductor device (1) comprises a source region (33), a drain region (14) and a drain drift region (11), the device having a field shaping region (20) adjacent the drift region (11) and arranged such that, in use, when a voltage is applied between the source (33) and drain (14) regions and the device is non-conducting, a substantially constant electric field is generated in the field shaping region (20) and accordingly in the adjacent drift region (11). The field shaping region (20), which may be intrinsic semiconductor, is arranged to function as a capacitor dielectric region (20) between a first capacitor electrode region (21) and a second capacitor electrode region (22), the first and second capacitor electrode regions (21, 22) being adjacent respective ends of the dielectric region (20) and having different electron energy barriers.

Abstract: A field effect transistor semiconductor device (1) comprises a source region (33), a drain region (14) and a drain drift region (11), the device having a field shaping region (20) adjacent the drift region (11) and arranged such that, in use, when a voltage is applied between the source (33) and drain (14) regions and the device is non-conducting, a substantially constant electric field is generated in the field shaping region (20) and accordingly in the adjacent drift region (11). The field shaping region (20), which may be intrinsic semiconductor, is arranged to function as a capacitor dielectric region (20) between a first capacitor electrode region (21) and a second capacitor electrode region (22), the first and second capacitor electrode regions (21, 22) being adjacent respective ends of the dielectric region (20) and having different electron energy barriers.

Abstract: The invention relates to a trench bipolar transistor structure, having a base 7, emitter 9 and collector 4, the latter being divided into a higher doped region 3 and a lower doped drift region 5. An insulated gate 11 is provided to deplete the drift region 5 when the transistor is switched off. The gate 11 and/or doping levels in the drift region 5 are arranged to provide a substantially uniform electric field in the drift region in this state, to minimise breakdown. In particular, the gate 11 may be seminsulating and a voltage applied along the gate between connections 21,23.

Abstract: A semiconductor device with a tunnel diode comprises two mutually adjoining semiconductor regions (2, 3) of opposed conductivity types having high enough doping concentrations to provide a tunneling junction. Portions (2A, 3A) of the semiconductor regions adjoining the junction comprise a mixed crystal of silicon and germanium. The doping concentration of both phosphorus and boron are substantially increased, given the same amount of dopants being offered as during the formation of the remainder of the regions. The tunneling efficiency is substantially improved, and also because of the reduced bandgap of said portions (2A, 3A). A much steeper current-voltage characteristic both in the forward and in the reverse direction is achieved. Thus, the tunneling pn junction can be used as a transition between two conventional diodes which are stacked one on the other and formed in a single epitaxial growing process. The doping concentration may be 6×1019 or even more than 1020 at/cm3.

Abstract: A semiconductor device with a tunnel diode (23) is particularly suitable for various applications. Such a device comprises two mutually adjoining semiconductor regions (2, 3) of opposed conductivity types and having doping concentrations which are so high that breakdown between them leads to conduction by means of tunnelling. A disadvantage of the known device is that the current-voltage characteristic is not yet steep enough for some applications.

Abstract: A semiconductor device with a tunnel diode (23) is particularly suitable for various applications. Such a device comprises two mutually adjoining semiconductor regions (2, 3) of opposed conductivity types and having doping concentrations which are so high that breakdown between them leads to conduction by means of tunnelling. A disadvantage of the known device is that the current-voltage characteristic is not yet steep enough for some applications. In a device according to the invention, the portions (2A, 3A) of the semiconductor regions (2, 3) adjoining the junction (23) comprise a mixed crystal of silicon and germanium. It is surprisingly found that the doping concentration of both phosphorus and boron are substantially increased, given the same amount of dopants being offered as during the formation of the remainder of the regions (2, 3).

Abstract: Very high resistance values may be necessary in integrated circuits, for example in the gigaohm range, for example for realizing RC times of 1 ms to 1 s. Such resistance values cannot or substantially not be realized by known methods in standard i.c. processes because of the too large space occupation. In addition, known embodiments are usually strongly dependent on the temperature. According to the invention, therefore, two zener diodes (10, 4; 11, 4) connected back-to-back are used as the resistor. The current through each zener diode is mainly determined by band--band tunneling when the voltage is not too high, for example up to approximately 0.2 V. This current has a value such that resistors in the giga range can be readily realized on a small surface area. Since the current is mainly determined by intrinsic material properties of silicon, the temperature dependence is very small. The resistor may furthermore be manufactured in any standard CMOS process or bipolar process.

Abstract: A semiconductor device includes a programmable element having a doped semiconductor region (4) and a conductor region (6) which are separated from one another by at least a portion of an insulating layer (5). The conductor region (6) is of a material suitable for forming a rectifying junction (8) with the material of the semiconductor region (4). To achieve a comparatively high conductivity connection to the semiconductor region (4), the element is further provided with a contact region (3) which has a comparatively low electrical resistance compared with the semiconductor region (4). The contact region (3) is provided at a side of the semiconductor region (4) remote from the insulating layer (5) and is separated from the insulating layer (5) by the semiconductor region (4). Both the semiconductor region (4) and the contact region (5) are laterally bounded by an isolating region (7) at opposing sides.

Abstract: A semiconductor device having a programmable memory cell which includes a bipolar transistor of which a base region (13) can be provided with a base current through a control transistor (7, 8, 9, 10). The bipolar transistor has an emitter region (12) connected to a first supply line (151) and has a collector region (14) connected to a second supply line (152) through a load (16). A constant potential difference is maintained between the two supply lines (151, 152) during operation. The collector region (14) is laterally electrically insulated and provides a feedback to the control transistor in such a manner that, during operation within a certain voltage domain, a change in the voltage difference between the emitter region (12) and the collector region (14) leads to an opposite change in the conductivity through the control transistor.