For example, a semiconductor device includes one or more first subcontacts electrically conducted to a substrate. At least one of the one or more first subcontacts is formed in an element arrangement region, and has a lower impedance than the substrate. Preferably, at least one of the one or more first subcontacts is adjacent to a circuit element formed in the element arrangement region. Preferably, on the substrate, which is of a first conductivity type, an epilayer of a second conductivity type is formed, and the one or more first subcontacts include a first line having a lower impedance than the substrate, and a semiconductor region of the first conductivity type penetrating through the epilayer to electrically conduct the first line and the substrate to each other.

An operational amplifier 1 comprises transistors Q1 and Q2 forming an input stage, and input resistors R1 and R2 which form a filter together with parasitic capacitors C1 and C2 accompanying the transistors Q1 and Q2. Resistance values R of the resistors R1 and R2 may be set to R=1/(2π.Math.fc.Math.C), where C is the capacitance value of each of the parasitic capacitors C1 and C2, and fc is the target cutoff frequency of the filter. The operational amplifier 1 may also include a power supply resistor R0 which forms a filter together with a parasitic capacitor C0 accompanying a power supply line.

A Darlington pair sensor is disclosed. The Darlington pair sensor has an amplifying/horizontal bipolar junction transistor (BJT) and a sensing/vertical BJT and can be used as a biosensor.

The amplifying bipolar junction transistor (BJT) is horizontally disposed on a substrate. The amplifying BJT has a horizontal emitter, a horizontal base, a horizontal collector, and a common extrinsic base/collector. The common extrinsic base/collector is an extrinsic base for the amplifying BJT.

The sensing BJT has a vertical orientation with respect to the amplifying BJT. The sensing BJT has a vertical emitter, a vertical base, an extrinsic vertical base, and the common extrinsic base/collector (in common with the amplifying BJT). The common extrinsic base/collector acts as the sensing BJT collector. The extrinsic vertical base is separated into a left extrinsic vertical base and a right extrinsic vertical base giving the sensing BJT has two separated (dual) bases, a sensing base and a control base.

The Darlington pair sensor has high in-situ signal amplification with low noise and uses substrate space effectively.

A six-transistor memory cell based upon a thyristor for an SRAM integrated circuit is described together with methods of operation. Methods of increasing the operational speed in reading the contents of a selected memory cell in an array of such memory cells while lowering power consumption, and of avoiding an indeterminate memory cell state when a memory cell is “awakened” from Standby are described.

The present invention is directed to a semiconductor chip comprising a high voltage device and a low voltage device disposed thereon. The chip may be formed in several different configurations. For example, the semiconductor chip may include a NPN bipolar transistor, PNP bipolar transistor, a diode, an N channel DMOS transistor and the like. the first doped well being configured as a base of the DMOS transistor, a P channel DMOS transistor and the like. These and other embodiments are described in further detail below.

An operational amplifier 1 comprises transistors Q1 and Q2 forming an input stage, and input resistors R1 and R2 which form a filter together with parasitic capacitors C1 and C2 accompanying the transistors Q1 and Q2. Resistance values R of the resistors R1 and R2 may be set to R=1/(2π.Math.fc.Math.C), where C is the capacitance value of each of the parasitic capacitors C1 and C2, and fc is the target cutoff frequency of the filter. The operational amplifier 1 may also include a power supply resistor R0 which forms a filter together with a parasitic capacitor C0 accompanying a power supply line.

A multi-transistor configuration including a first transistor having a first terminal that is configured to control the flow of current between, a second terminal of the first transistor and a third terminal of the first transistor; a second transistor, that is a bipolar junction transistor comprising a base terminal, an emitter terminal, and a collector terminal, wherein the third terminal of the first transistor and the collector terminal of the second transistor are electrically connected; and a first voltage source having a first terminal at a first voltage and a second terminal at a second voltage.

A method of subdividing a semiconductor wafer is described with trenches in order to provide separate, electrically isolated regions that can be used to hold components that operate at different voltages. There is also described a masking and etching process of forming collector and emitter regions of a lateral bipolar transistor, from a layer of polysilicon deposited on a patterned later of silicon dioxide.

A semiconductor device is provided in which a zener diode having a desired breakdown voltage and a capacitor in which voltage dependence of capacitance is reduced are mounted together, and various circuits are realized. The semiconductor device includes: a semiconductor layer; a first conductivity type well that is arranged in a first region of the semiconductor layer; a first conductivity type first impurity diffusion region that is arranged in the well; a first conductivity type second impurity diffusion region that is arranged in a second region of the semiconductor layer; an insulating film that is arranged on the second impurity diffusion region; an electrode that is arranged on the insulating film; and a second conductivity type third impurity diffusion region that is arranged at least on the first impurity diffusion region.

An operational amplifier 1 comprises transistors Q1 and Q2 forming an input stage, and input resistors R1 and R2 which form a filter together with parasitic capacitors C1 and C2 accompanying the transistors Q1 and Q2. Resistance values R of the resistors R1 and R2 may be set to R=1/(2π.Math.fc.Math.C), where C is the capacitance value of each of the parasitic capacitors C1 and C2, and fc is the target cutoff frequency of the filter. The operational amplifier 1 may also include a power supply resistor R0 which forms a filter together with a parasitic capacitor C0 accompanying a power supply line.