U.S. Philips Corporation

Godefridus A Hurkx

Evert Seevinck

Cornelis Maria Hart

Jan W Slotboom

Andreas Hubertus Montree

Maarten Vertregt

Petrus G Baltus

Willem Van Der Wel

Catharina H Emons

Marinus P Knuvers

The continuing miniaturization of integrated circuits leads to a demand for ever higher resistance values. In conventional diffused resistors or poly resistors, an increase in the resistance value also means an increase in the surface area. Such resistors, moreover, are highly dependent on the doping concentration and sensitive to temperature changes. A resistor according to the invention comprises a resistor region 18 with a length and doping concentration which are chosen such that an electric field is applied at which velocity saturation of charge carriers takes place in the envisaged range of operation. The connection regions are connected to the resistor region via rectifying junctions 21, 22. In a specific embodiment, these junctions are formed by pn junctions, so that the resistor has, for example, an npn shape. The dimensions are furthermore chosen such that, within said operational range, electrons are injected into the p-type resistor regions by punch-through between the n-type connection regions 19, 20, traversing the resistor region at the saturation velocity. Since the charge carriers supplying the current are of the type opposed to that of the resistor material, it is prevented that the resistance value becomes very low at low voltages.

Punch-through resistor

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.

Semiconductor resistor using back-to-back zener diodes

A device compensated for an undesired capacitance includes a first and a second node between which nodes the undesired capacitance is present. A diode driven in breakthrough is coupled between the first and the second node. As a diode driven in breakthrough exhibits the characteristics of a negative capacitance, a compensation of the undesired capacitance is achieved.

Electronic device comprising means for compensating an undesired

A semiconductor device with at least one programmable memory cell which includes a bipolar transistor (T.sub.1) with an emitter (11) and a collector (12) of a first conductivity type and a base (10) of a second, opposite conductivity type. The emitter (11) and collector (12) are coupled to a first supply line (100) and a second supply line (200), respectively. The base (10) is coupled to writing means (WRITE) through a control transistor (T.sub.2). Reading means (READ) are included in a current path (I) which extends between the first supply line (100) and the second supply line (200) and which includes a current path between the emitter (11) and collector (12). In a preferred embodiment, the collector (12) is in addition coupled to the second supply line (200) via a switchable load (T.sub.5).

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Eindhoven, Netherlands

Godefridus A Hurkx