摘要:
A method of manufacturing a semiconductor device comprising heterojunction bipolar transistors (HBTs), in which method a first semiconductor layer of monocrystalline silicon (5), a second semiconductor layer of monocrystalline silicon comprising 5 to 25 at. % germanium (6) and a third semiconductor layer of monocrystalline silicon (7) are successively provided on a surface (2) of a silicon wafer (1) by means of epitaxial deposition. Base zones of the transistors are formed in the second semiconductor layer. In this method, the second semiconductor layer is deposited without a base doping, said doping being formed at a later stage. Said doping can be formed by means of an ion implantation process or a VPD (Vapor Phase Doping) process. This method enables integrated circuits comprising npn-transistors as well as pnp-transistors to be manufactured.
摘要:
A semiconductor arrangement including: a substrate having a substrate layer (13) with an upper and lower surface, the substrate layer (13) being of a first conductivity type; a first buried layer (12) in the substrate, extending along said lower surface below a first portion of said upper surface of said substrate layer (13), and a second buried layer (12) in the substrate, extending along said lower surface below a second portion of said upper surface of said substrate layer (13); a first diffusion (26) in said first portion of said substrate layer (13), being of a second conductivity type opposite to said first conductivity type and having a first distance to said first buried layer (12) for defining a first breakdown voltage between said first diffusion (26) and said first buried layer (12); a second diffusion (45) in said second portion of said substrate layer (13), being of said second conductivity type and having a second distance to said second buried layer (12) for defining a second breakdown voltage between said second diffusion (45) and said second buried layer (12); said first distance being larger than said second distance such that said first breakdown voltage is larger than said second breakdown voltage.
摘要:
The invention relates to an essentially discrete semiconductor device comprising a semiconductor body (10) having a first, preferably bipolar, transistor (T1) with a first region (1) forming a collector (1) of T1, and a second, preferably also bipolar, transistor (T2) with a second region (2) forming a collector (2) of T2, which transistors (T1, T2) are in a cascode configuration wherein the collector (1) of T1is connected to the emitter (4) of T2. Such a device cannot suitably be used in a base station for mobile communication. According to the invention, the first region (1) and the second region (2) are positioned next to each other within a semiconductor region (5), a part of which situated below the first region (1) is provided with a higher doping concentration at the location of T1. In this way, T1 has a low collector-emitter breakdown voltage and a high cutoff frequency, whereas for T2 said voltage and frequency are, respectively, high(er) and low(er). The resultant device is very suitable, on the one hand, for a high voltage application, for example 28 V, and a high power application, for example 100 W and, on the other hand, the device can still operate at a very high speed and hence is very suitable for the above application. Moreover, the device can be manufactured very easily using a method according to the invention. Preferably, the device is rendered suitable for surface mounting, and the semiconductor body is attached to an isolating substrate (20), while the parts thereof that are situated outside T1 and T2 are removed.
摘要:
The LDMOS transistor (1) of the invention comprises a source region (3), a channel region (4), a drain extension region (7) and a gate electrode (10). The LDMOS transistor (1) further comprises a first gate oxide layer (8) and a second gate oxide layer (9), which is thicker than the first gate oxide layer (8). The first gate oxide layer (8) at least extends over a first portion of the channel region (4), which is adjacent to the source region (3). The second gate oxide layer (9) extends over a region where a local maximum (A, B) of the electric field (E) generates hot carriers thereby reducing the impact of the hot carriers and reducing the Idq-degradation. In another embodiment the second gate oxide layer (9) extends over a second portion of the channel region (4), which mutually connects the drain extension region (7) and the first portion of the channel region (4), thereby improving the linear efficiency of the LDMOS transistor (1).
摘要:
The LDMOS transistor (99) of the invention is provided with a stepped shield structure (50) and/or with a first (25) and a second (26) drain extension region having a higher dopant concentration than the second drain extension region, and being covered by the shield.
摘要:
System and method for compensating for changes in an output impedance of a power amplifier uses an impedance compensating circuit with an impedance inverter coupled to the power amplifier. The impedance inverter of the impedance compensating circuit is configured such that an output impedance of the impedance inverter is proportional to the inverse of the output impedance of the power amplifier to compensate for changes in the output impedance of the power amplifier.
摘要:
The LDMOS transistor (99) of the invention is provided with a stepped shield structure (50) and/or with a first (25) and a second (26) drain extension region having a higher dopant concentration than the second drain extension region, and being covered by the shield.
摘要:
The invention relates to a semiconductor device (100) with a semiconductor body (10) comprising at least one semiconductor element (H) with an active area (A) and a coil (20) coupled to said element (H). The coil (20) and a further coil (21) jointly form a transformer (F). The semiconductor body (10) is secured to a carrier plate (30) which comprises an electrically insulating material and is covered with a conductor track (21). According to the invention, the further coil (21) is positioned on the carrier plate (30) and is formed by the conductor track (21) and electrically separated from the coil (20). In this way, a-device (100) is obtained which is easier to manufacture than the known device. Moreover, the communication between the element (H) and the outside world does not involve an electrical coupling and hence, for example, bonding wires, are not necessary. The invention is particularly advantageous for a (discrete) bipolar transistor, which can suitably be used for surface mounting. The invention further comprises an easy method of manufacturing a device (100) according to the invention.
摘要:
The invention relates to a semiconductor device comprising a bipolar transistor having a collector (1), a base (2) and an emitter (3) at its active area (A). The semiconductor body (10) of the device is covered with an insulating layer (20). At least a part of a base connection conductor (5) and an emitter connection conductor (6) extend over the insulating layer (20) and lead to a base connection area (8) and an emitter connection area (9), respectively. The known transistor is characterized by poor gain, particularly at high frequencies and at high power. A device according to the invention is characterized in that the emitter connection area (8) and the base connection area (9), viewed in projection, are present on the same side of the active area (A), the emitter connection conductor (6) is divided into two or more sub-conductors (6A, 6B) and the base connection conductor (5) is divided into one or more further sub-conductors (5) which are present between the sub-conductors (6A, 6B) and form a co-planar transmission line (T) therewith. In this way, the inductance of the emitter connection conductor (6) is reduced considerably, resulting in a much higher gain, particularly at high frequencies and high power. Preferably, the semiconductor body (A) is interrupted at the area of the transmission line (T) and is glued to an insulating substrate (40).
摘要:
The LDMOS transistor (1) of the invention comprises a source region (3), a channel region (4), a drain extension region (7) and a gate electrode (10). The LDMOS transistor (1) further comprises a first gate oxide layer (8) and a second gate oxide layer (9), which is thicker than the first gate oxide layer (8). The first gate oxide layer (8) at least extends over a first portion of the channel region (4), which is adjacent to the source region (3). The second gate oxide layer (9) extends over a region where a local maximum (A, B) of the electric field (E) generates hot carriers thereby reducing the impact of the hot carriers and reducing the Idq-degradation. In another embodiment the second gate oxide layer (9) extends over a second portion of the channel region (4), which mutually connects the drain extension region (7) and the first portion of the channel region (4), thereby improving the linear efficiency of the LDMOS transistor (1).