Abstract: An adaptive charge balanced MOSFET device includes a field plate stacks, a gate structure, a source region, a drift region and a body region. The gate structure includes a gate region surrounded by a gate insulator region. The field plate stack includes a plurality of field plate insulator regions, a plurality of field plate regions, and a field ring region. The plurality of field plates are separated from each other by respective field plate insulators. The body region is disposed between the gate structure, the source region, the drift region and the field ring region. Each of two or more field plates are coupled to the field ring.

Abstract: A MOS device for reducing an antenna effect is provided. The MOS device includes a diode including a first nMOS transistor having a first nMOS transistor source, a first nMOS transistor drain, a first nMOS transistor gate, and an nMOS transistor body. The nMOS transistor body is coupled to a first voltage source and is an anode of the diode. The first nMOS transistor source, the first nMOS transistor drain, and the first nMOS transistor gate are coupled together and are a cathode of the diode. The MOS device further includes an interconnect extending between a driver output and a load input. The interconnect is coupled to the cathode of the diode. The interconnect may extend on one metal layer only between the driver output and the load input.

Abstract: A differential pair sensing circuit (300) includes control gates (306, 316) for separately programming a reference transistor (350) and a chemically-sensitive transistor (351) to a desired threshold voltage Vt to eliminate the mismatch between the transistors in order to increase the sensitivity and/or accuracy of the sensing circuit without increasing the circuit size.

Abstract: A semiconductor device has a channel layer formed above a substrate, a barrier layer formed over the channel layer and having a band gap larger than that of the channel layer, a trench passing through the barrier layer as far as a midway of the channel layer, and a gate electrode disposed byway of a gate insulation film in the inside of the trench. Then, the end of the bottom of the trench is in a rounded shape and the gate insulation film in contact with the end of the bottom of the trench is in a rounded shape. By providing the end of the bottom of the trench with a roundness as described above, a thickness of the gate insulation film situated between the end of the bottom of the gate electrode and the end of the bottom of the trench can be decreased. Thus, the channel is formed also at the end of the bottom of the trench to reduce the resistance of the channel.

Abstract: An improved method of fabricating an interdigitated back contact (IBC) solar cell is disclosed. A first mask is used to perform a patterned ion implantation of n-type dopant to create the back surface field. A second mask is then used to create the p-type emitter on the same surface. The second mask may be aligned to the n-type implant, and may be used in a plurality of orientations to create the desired p-type emitter. In some embodiments, a p-type blanket implant is performed as well. In some embodiments, a doping gradient is created.

Abstract: The invention provides a method for fabricating a transistor and a transistor, wherein the method for fabricating a transistor includes: growing a second oxide layer on the surface of a substrate on which a first oxide layer and a first base region are formed, wherein the second oxide layer is formed above the first base region; forming an emitter region in a first preset area on the second oxide layer; forming a contact hole in a second preset area on the second oxide layer, wherein the second preset area does not overlap with the first preset area; injecting doping elements into the surface of the first base region in the area of the contact hole; and thermally processing the substrate to activate the doping elements to form a second base region.

Abstract: A method for producing semiconductor regions including impurities includes forming a trench in a first surface of a semiconductor body. Impurity atoms are implanted into a bottom of the trench. The trench is extended deeper into the semiconductor body, thereby forming a deeper trench. Impurity atoms are implanted into a bottom of the deeper trench.

Abstract: Some structures and methods to reduce power consumption in devices can be implemented largely by reusing existing bulk CMOS process flows and manufacturing technology, allowing the semiconductor industry as well as the broader electronics industry to avoid a costly and risky switch to alternative technologies. Some of the structures and methods relate to a Deeply Depleted Channel (DDC) design, allowing CMOS based devices to have a reduced sVT compared to conventional bulk CMOS and can allow the threshold voltage VT of FETs having dopants in the channel region to be set much more precisely. The DDC design also can have a strong body effect compared to conventional bulk CMOS transistors, which can allow for significant dynamic control of power consumption in DDC transistors. Additional structures, configurations, and methods presented herein can be used alone or in conjunction with the DDC to yield additional and different benefits.

Abstract: A method for fabricating a capacitor includes: forming a storage node contact plug over a substrate; forming an insulation layer having an opening exposing a surface of the storage node contact plug over the storage contact plug; forming a conductive layer for a storage node over the insulation layer and the exposed surface of the storage node contact plug through two steps performed at different temperatures; performing an isolation process to isolate parts of the conductive layer; and sequentially forming a dielectric layer and a plate electrode over the isolated conductive layer.

Abstract: A system and method for controlling a dosage profile is disclosed. An embodiment comprises separating a wafer into components of a grid array and assigning each of the grid components a desired dosage profile based upon a test to compensate for topology differences between different regions of the wafer. The desired dosages are decomposed into directional dosage components and the directional dosage components are translated into scanning velocities of the ion beam for an ion implanter. The velocities may be fed into an ion implanter to control the wafer-to-beam velocities and, thereby, control the implantation.

Abstract: Device structures, fabrication methods, and design structures for a bipolar junction transistor. An intrinsic base is formed on the substrate, a terminal is formed on the intrinsic base, and an extrinsic base is formed that is arranged in juxtaposition with the intrinsic base on the substrate. The intrinsic base and terminal are respectively comprised of first and second semiconductor materials.

Abstract: A method that forms a structure implants a well implant into a substrate, patterns a mask on the substrate (to have at least one opening that exposes a channel region of the substrate) and forms a conformal dielectric layer on the mask and to line the opening. The conformal dielectric layer covers the channel region of the substrate. The method also forms a conformal gate metal layer on the conformal dielectric layer, implants a compensating implant through the conformal gate metal layer and the conformal dielectric layer into the channel region of the substrate, and forms a gate conductor on the conformal gate metal layer. Additionally, the method removes the mask to leave a gate stack on the substrate, forms sidewall spacers on the gate stack, and then forms source/drain regions in the substrate partially below the sidewall spacers.

Abstract: A method of selectively forming a germanium structure within semiconductor manufacturing processes removes the native oxide from a nitride surface in a chemical oxide removal (COR) process and then exposes the heated nitride and oxide surface to a heated germanium containing gas to selectively form germanium only on the nitride surface but not the oxide surface.

Abstract: Transistors with memorized stress and methods for making such transistors. The methods include forming a transistor structure having a channel region, a source and drain region, and a gate dielectric; depositing a stressor over the channel region of the transistor structure, wherein the stressor provides a stress to the channel region; removing the stressor metal after the stress is memorized within the channel region; and depositing a work function metal over the channel region of the transistor structure, where the work function metal applies less stress to the channel region than the stress applied by the stressor. A transistor with memorized stress includes a source and drain region on a substrate; a stress-memorized channel region on the substrate that retains an externally applied stress; and a gate structure including a work function gate metal that applies less stress to the stress-memorized channel region than the externally applied stress.

Abstract: A transistor and method of fabrication thereof includes a screening layer formed at least in part in the semiconductor substrate beneath a channel layer and a gate stack, the gate stack including spacer structures on either side of the gate stack. The transistor includes a shallow lightly doped drain region in the channel layer and a deeply lightly doped drain region at the depth relative to the bottom of the screening layer for reducing junction leakage current. A compensation layer may also be included to prevent loss of back gate control.

Abstract: In a method of manufacturing a reverse-blocking semiconductor element, a tapered groove is formed and ions are implanted into a rear surface and the tapered groove. Then, a furnace annealing process and a laser annealing process are performed to form a rear collector layer and a separation layer on the side surface of the tapered groove. In this way, it is possible to ensure a reverse breakdown voltage and reduce a leakage current when a reverse bias applied, even in a manufacturing method including a process of manufacturing a diffusion layer formed by forming a tapered groove and performing ion implantation and an annealing process for the side surface of the tapered groove as the separation layer for bending the termination of a reverse breakdown voltage pn junction to extend to the surface.

Abstract: A method of forming a device is presented. The method includes providing a substrate having a device region which includes a source region, a gate and a drain region defined thereon. The method also includes implanting the gate. The gate comprises one or more doped portions with different dopant concentrations. A source and a drain are formed in the source region and drain region. The drain is separated from the gate on a second side of the gate and the source is adjacent to a first side of the gate.

Abstract: This invention discloses a semiconductor power device disposed in a semiconductor substrate and having an active cell area and an edge termination area the edge termination area wherein the edge termination area comprises a superjunction structure having doped semiconductor columns of alternating conductivity types with a charge imbalance between the doped semiconductor columns to generate a saddle junction electric field in the edge termination.

Abstract: An integrated circuit containing a bipolar transistor including an emitter diffused region with a peak doping density higher than 1·1020 atoms/cm3, and an emitter-base junction less than 40 nanometers deep in a base layer. A process of forming the bipolar transistor, which includes forming an emitter dopant atom layer between a base layer and an emitter layer, followed by a flash or laser anneal step to diffuse dopant atoms from the emitter dopant atom layer into the base layer.

Abstract: A method and system are disclosed for doping a semiconductor substrate. In one embodiment, the method comprises forming a carbon free layer of phosphoric acid on a semiconductor substrate, and diffusing phosphorous from the layer of phosphoric acid in the substrate to form an activated phosphorous dopant therein. In an embodiment, the semiconductor substrate is immersed in a solution of a phosphorous compound to form a layer of the phosphorous compound on the substrate, and this layer of phosphorous is processed to form the layer of phosphoric acid. In an embodiment, this processing may include hydrolyzing the layer of the phosphorous compound to form the layer of phosphoric acid. In one embodiment, an oxide cap layer is formed on the phosphoric acid layer to form a capped substrate. The capped substrate may be annealed to diffuse the phosphorous in the substrate and to form the activated dopant.

Abstract: An LDMOS transistor includes a substrate of semiconductor material, an insulator layer overlying the substrate, a semiconductor layer overlying the insulator layer, a RESURF region, and a gate. The semiconductor layer includes a first conductivity type well region, a second conductivity type source region in contact with the first conductivity type well region, a second conductivity type drain region. The RESURF region includes at least one first conductivity type material portion, and at least one portion of the at least one first conductivity type material portion electrically coupled to the first conductivity type well region. A semiconductor material having a second conductivity type is located below the RESURF region. The second conductivity type semiconductor material is also located over a part of the RESURF region. The gate is located over the first conductivity type well region and over the RESURF region.

Abstract: A method and structures are provided for implementing deep trench enabled high current capable bipolar transistor for current switching and output driver applications. A deep oxygen implant is provided in a selected region of substrate. A first deep trench and second deep trench are formed above the deep oxygen implant. The first deep trench is a generally large rectangular box deep trench of minimum width and the second deep trench is a second small area deep trench centered within the first rectangular box deep trench. Ion implantation at relatively high ion pressure and annealing is utilized to form highly doped N+ regions or P+ regions both inside and outside the outside the first deep trench and around the outside the second deep trench region. These regions provide the collector and emitter respectively, and the existing substrate region provides the base region between the collector and emitter regions.

Abstract: A method of forming a pattern of doped region includes the following steps. At first, a device layout pattern including a gate layout pattern and a doped region layout pattern is provided to a computer system. Subsequently, the device layout pattern is split into a plurality of sub regions, and the sub regions have different pattern densities of the gate layout pattern. Then, at least an optical proximity correction (OPC) calculation is respectively performed on the doped region layout pattern in each of the sub regions to respectively form a corrected sub doped region layout pattern in each of the sub regions. Afterwards, the corrected sub doped region layout patterns are combined to form a corrected doped region layout pattern, and the corrected doped region layout pattern is outputted onto a mask through the computer system.

Abstract: An improved method of tilting a mask to perform a pattern implant of a substrate is disclosed. The mask has a plurality of apertures, and is placed between the ion source and the substrate. The mask and substrate are tilted at a first angle relative to the incoming ion beam. After the substrate is exposed to the ion beam, the mask and substrate are tilted at a second angle relative to the ion beam and a subsequent implant step is performed. Through the selection of the aperture size and shape, the cross-section of the mask, the distance between the mask and the substrate and the number of implant steps, a variety of implant patterns may be created. In some embodiments, the implant pattern includes heavily doped horizontal stripes with lighter doped regions between the stripes. In some embodiments, the implant pattern includes a grid of heavily doped regions.

Abstract: A semiconductor device and manufacturing method thereof capable of improving an operating speed of a MOSFET using an inexpensive structure. The method comprises the steps of forming a stress film to cover a source, drain, sidewall insulating layer and gate of the MOSFET and forming in the stress film a slit extending from the stress film surface toward the sidewall insulating layer. As a result, an effect of allowing local stress components in the stress films on the source and the drain to be relaxed by local stress components in the stress film on the gate is suppressed by the slit.

Abstract: Lateral collection architecture for a photodetector is achieved by depositing electrically conducting SLS layers onto a planar substrate and diffusing dopants of a carrier type opposite that of the layers through the layers at selected regions to disorder the superlattice and create diode junctions oriented transversely to the naturally enhanced lateral mobility of photogenerated charge carriers within the superlattice. The diode junctions are terminated at a top surface of the photodetector within an SLS layer of wide bandgap material to minimize unwanted currents. A related architecture disorders the superlattice of topmost SLS layers by diffusing therethrough a dopant configured as a grid and penetrating to a lower SLS layer having the same carrier type as the dopant and opposite that of the topmost layers to isolate pixels within the topmost layers. Ohmic contacts may be deposited on doped regions, pixels, and substrate to provide desired external connections.

Abstract: The product of the breakdown voltage (BVCEO) and the cutoff frequency (fT) of a SiGe heterojunction bipolar transistor (HBT) is increased beyond the Johnson limit by utilizing a doped region with a hollow core that extends down from the base to the heavily-doped buried collector region. The doped region and the buried collector region have opposite dopant types.

Abstract: In one embodiment, a method includes forming a base region for a transistor using a base mask and forming a contact region to the base region. The contact region is formed in an area that is at least partially outside of the base mask. The method then forms an emitter region in a diffused base region. The base region diffuses outwardly to be formed under the contact region.

Abstract: An LDMOS transistor includes a substrate of semiconductor material, an insulator layer overlying the substrate, a semiconductor layer overlying the insulator layer, a RESURF region, and a gate. The semiconductor layer includes a first conductivity type well region, a second conductivity type source region in contact with the first conductivity type well region, a second conductivity type drain region. The RESURF region includes at least one first conductivity type material portion, and at least one portion of the at least one first conductivity type material portion electrically coupled to the first conductivity type well region. A semiconductor material having a second conductivity type is located below the RESURF region. The second conductivity type semiconductor material is also located over a part of the RESURF region. The gate is located over the first conductivity type well region and over the RESURF region.

Abstract: A manufacturing method for a high voltage transistor includes the following steps. A substrate is provided. A P-type epitaxial (P-epi) layer is provided above the substrate. An N-well is formed in the P-epi layer. A P-well is formed in the P-epi layer. Field oxide (FOX) layers are formed above the P-epi layer. A gate oxide (GOX) layer is formed between the FOX layers. P-type implants are doped into the P-well or N-type implants are doped into the N-well to adjust an electrical function of the high voltage transistor.

Abstract: Field effect transistors and method for forming filed effect transistors. The field effect transistors including: a gate dielectric on a channel region in a semiconductor substrate; a gate electrode on the gate dielectric; respective source/drains in the substrate on opposite sides of the channel region; sidewall spacers on opposite sides of the gate electrode proximate to the source/drains; and wherein the sidewall spacers comprise a material having a dielectric constant lower than that of silicon dioxide and capable of absorbing laser radiation.

Abstract: In accordance with an embodiment of the present invention a transistor is disclosed. The transistor comprises a collector, a base and an emitter, wherein a first end width of the base is larger than a middle width of the base, wherein a first end width of the collector is larger than a middle width of the collector, or wherein a first end width of the emitter is larger than a middle width of the emitter.

Abstract: A method for forming a submicron device includes depositing a hard mask over a first region that includes a polysilicon well of a first dopant type and a gate of a second dopant type and a second region that includes a polysilicon well of a second dopant type and a gate of a first dopant type. The hard mask over the first region is removed. Angled implantation of the first dopant type is performed to form pockets under the gate of the second dopant type.

Abstract: An NPN bipolar junction transistor is disclosed that exhibits a collector-to-emitter breakdown voltage greater than 10 volts and a beta greater than 300. The large value of beta is obtained by fabricating the transistor with an extra IN-type layer that reduces recombination of electrons and holes.

Abstract: A wafer, a fabricating method of the same, and a semiconductor substrate are provided. The wafer includes a first substrate layer formed at a first surface, a second substrate layer formed at a second surface opposite to the first surface, the second substrate layer having a greater oxygen concentration than the first substrate layer, and an oxygen diffusion protecting layer formed between the first substrate layer and the second substrate layer, the oxygen diffusion protecting layer being located closer to the first surface than to the second surface.

Abstract: A first species is implanted into an entire surface of a workpiece and helium is implanted into this entire surface with a non-uniform dose. The first species may be, for example, hydrogen, helium, or nitrogen. The helium has a higher dose at a portion of a periphery of the workpiece. When the workpiece is split, this split is initiated at the periphery with the higher dose. The non-uniform dose may be formed by altering a scan speed of the workpiece or an ion beam current of the helium. In one instance, the non-uniform dose of the helium is larger than a uniform dose of the hydrogen.

Abstract: A method and system are disclosed for doping a semiconductor substrate. In one embodiment, the method comprises forming a carbon free layer of phosphoric acid on a semiconductor substrate, and diffusing phosphorous from the layer of phosphoric acid in the substrate to form an activated phosphorous dopant therein. In an embodiment, the semiconductor substrate is immersed in a solution of a phosphorous compound to form a layer of the phosphorous compound on the substrate, and this layer of phosphorous is processed to form the layer of phosphoric acid. In an embodiment, this processing may include hydrolyzing the layer of the phosphorous compound to form the layer of phosphoric acid. In one embodiment, an oxide cap layer is formed on the phosphoric acid layer to form a capped substrate. The capped substrate may be annealed to diffuse the phosphorous in the substrate and to form the activated dopant.

Abstract: Disclosed is an improved semiconductor structure (e.g., a silicon germanium (SiGe) hetero-junction bipolar transistor) having a narrow essentially interstitial-free SIC pedestal with minimal overlap of the extrinsic base. Also, disclosed is a method of forming the transistor which uses laser annealing, as opposed to rapid thermal annealing, of the SIC pedestal to produce both a narrow SIC pedestal and an essentially interstitial-free collector. Thus, the resulting SiGe HBT transistor can be produced with narrower base and collector space-charge regions than can be achieved with conventional technology.

Abstract: A method for decreasing polysilicon gate resistance in a carbon co-implantation process which includes: depositing a first salicide block layer on a formed gate of a MOS device and etching it to form a first spacer of a side surface of the gate of the MOS device; performing a P-type heavily doped boron implantation process and a thermal annealing treatment, so as to decrease the resistance of the polysilicon gate; removing said first spacer, performing a lightly doped drain process, and performing a carbon co-implantation process at the same time, so as to form ultra-shallow junctions at the interfaces between a substrate and source region and drain region below the gate; re-depositing a second salicide block layer on the gate and etching the mask to form a second spacer; forming a self-aligned silicide on the surface of the MOS device. The invention can decrease the resistance of the P-type polysilicon gate.

Abstract: A manufacturing method for a high voltage transistor includes the following steps. A substrate is provided. A P-type epitaxial (P-epi) layer is provided above the substrate. An N-well is formed in the P-epi layer. A P-well is formed in the P-epi layer. Field oxide (FOX) layers are formed above the P-epi layer. A gate oxide (GOX) layer is formed between the FOX layers. P-type implants are doped into the P-well or N-type implants are doped into the N-well to adjust an electrical function of the high voltage transistor.

Abstract: In a semiconductor film having a heterojunction structure, for example a semiconductor film including a SiGe layer and a Si layer formed on the SiGe layer, impurity concentration is controlled in such a manner that the concentration of impurity in the lower, SiGe layer becomes higher than that in the upper, Si layer by exploiting the fact that there is a difference between the SiGe layer and the Si layer in the diffusion coefficient of the impurity. The impurity contained in the semiconductor film 11 is of the conductivity type opposite to that of the transistor (p-type in the case of an n-type MOS transistor whereas n-type in the case of a p-type MOS transistor). In this way, the mobility in a semiconductor device including a semiconductor film having a heterojunction structure with a compression strain structure is increased, thereby improving the transistor characteristics and reliability of the device.

Abstract: The present technology discloses a bipolar junction transistor (BJT) device integrated into a semiconductor substrate. The BJT device comprises a collector, a base and an emitter. The collector is of a first doping type on the substrate; the base is of a second doping type in the collector from the top surface of the semiconductor device and the base has a base depth; and the emitter is of a first doping type in the base from the top surface of the semiconductor device. The base depth is controlled by adjusting a layout width in forming the base.

Abstract: A method of forming a self-aligned well implant for a transistor includes forming a patterned gate structure over a substrate, including a gate conductor, a gate dielectric layer and sidewall spacers, the substrate including an undoped semiconductor layer beneath the gate dielectric layer and a doped semiconductor layer beneath the undoped semiconductor layer; removing portions of the undoped semiconductor layer and the doped semiconductor layer left unprotected by the patterned gate structure, wherein a remaining portion of the undoped semiconductor layer beneath the patterned gate structure defines a transistor channel and a remaining portion of the doped semiconductor layer beneath the patterned gate structure defines the self-aligned well implant; and growing a new semiconductor layer at locations corresponding to the removed portions of the undoped semiconductor layer and the doped semiconductor layer, the new semiconductor layer corresponding to source and drain regions of the transistor.

Abstract: The disclosure provides a semiconductor device and method of manufacture therefore. The method for manufacturing the semiconductor device, in one embodiment, includes forming a layer of gate electrode material over a layer of gate dielectric material, wherein the layer of gate dielectric material is positioned over a substrate (210). This method further includes patterning the layer of gate electrode material and the layer of gate dielectric material into an NMOS gate structure (230), wherein the NMOS gate structure (230) includes an NMOS gate dielectric (240) and an NMOS gate electrode (250). This method further includes forming n-type source/drain regions (710) within the substrate (210) proximate the NMOS gate structure (230), and siliciding the NMOS gate electrode (250) to form a silicided gate electrode (1110, 1210). This method additionally includes placing a p-type dopant within the layer of gate electrode material or the NMOS gate electrode (250) prior to or concurrently with siliciding.

Abstract: A semiconductor device includes a first transistor having a threshold voltage (Vth) adjusted to a first Vth by a first dopant having a first peak of concentration at a first depth; and a second transistor having the same channel-type as that of the first transistor and having a Vth adjusted to a second Vth by a second dopant having a second peak of concentration at a second depth equal to the first depth and higher concentration than the first dopant; wherein the first dopant and the second dopant are dopants comprising the same constituent element.

Abstract: A semiconductor device, an integrated circuit, and method for fabricating the same are disclosed. The semiconductor device includes a gate stack formed on an active region of a silicon-on-insulator substrate. A gate spacer is formed over the gate stack. A source region that includes embedded silicon germanium is formed within the semiconductor layer. A drain region that includes embedded silicon germanium is formed within the semiconductor layer. The source region includes an angled implantation region that extends into the embedded silicon germanium of the source region, and is asymmetric relative to the drain region.

Abstract: A method of fabricating a transistor is provided. The transistor includes a SiGe epitaxial layer formed in a recess region of a substrate at both side of a gate electrode and a SiGe capping layer formed on the SiGe epitaxial layer. The transistor further includes a SiGe seed layer formed under the SiGe epitaxial layer and a silicon capping layer formed on the SiGe capping layer.

Abstract: An improved method of doping a substrate is disclosed. The method is particularly beneficial to the creation of interdigitated back contact (IBC) solar cells. A patterned implant is performed to introduce a first dopant to a portion of the solar cell. After this implant is done, an oxidation layer is grown on the surface. The oxide layer grows more quickly over the implanted region than over the non-implanted region. An etching process is then performed to remove a thickness of oxide, which is equal to the thickness over the non-implanted regions. A second blanket implant is then performed. Due to the presence of oxide on portions of the solar cell, this blanket implant only implants ions in those regions which were not implanted previously.

Abstract: A thin film transistor (TFT) formed on a substrate includes a polycrystalline film, a gate insulator, a hydrogen-supplying film and a gate electrode. The polycrystalline film is formed on the substrate. Two sides of the polycrystalline film serve as the source and the drain of the semiconductor device, and the central region of the polycrystalline layer serves as the channel. The gate insulator is formed on the polycrystalline film, then the polycrystalline film is ions implanted, and the hydrogen-supplying film is formed on the gate insulator. The gate electrode is formed on the hydrogen-supplying film above the channel. The hydrogen-supplying film supplies hydrogen to the polycrystalline film, especially to the channel, so as to transform the unsaturated bonds into hydrogen bonds in the channel for avoiding the unsaturated bonds to degrade the charge carrier efficiency of the channel.

Abstract: In accordance with an embodiment of the present invention a transistor is disclosed. The transistor comprises a collector, a base and an emitter, wherein a first end width of the base is larger than a middle width of the base, wherein a first end width of the collector is larger than a middle width of the collector, or wherein a first end width of the emitter is larger than a middle width of the emitter.