Active solid-state devices (e.g. – transistors – solid-state diode – Integrated circuit structure with electrically isolated... – Including dielectric isolation means
Reexamination Certificate
1999-12-17
2001-05-15
Meier, Stephen D. (Department: 2822)
Active solid-state devices (e.g., transistors, solid-state diode
Integrated circuit structure with electrically isolated...
Including dielectric isolation means
C257S544000, C257S531000, C455S073000, C330S303000
Reexamination Certificate
active
06232645
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims priority from prior French Patent Application No. 98-15941, filed Dec. 17, 1998, the entire disclosure of which is herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to semiconductor devices, and more specifically to decoupling between a noise emitter and a noise-sensitive receiver that are in an integrated circuit formed on a substrate that is suited for BiCMOS technology.
2. Description of Related Art
The coupling noise inside an integrated circuit comes essentially from two sources, namely the electromagnetic coupling due to the package and the metal lines of the circuit, and the electrical coupling due to the substrate. The present invention is concerned with reducing the electrical coupling noise due to the substrate. When a noise emitter injects charges into the substrate, they are distributed uniformly and can then be picked up by a receiver whose operation may be perturbed if it is sensitive to this electrical noise. For example, a “noise emitter” in the context of this description can be a strong-signal transistor that injects charges into the substrate, and the charges can be picked up by a weak-signal transistor that then behaves as a noise-sensitive receiver.
As an exemplary environment, such coupling noise will be described in relation to the field of mobile telephones. After a radio frequency reception stage, a mobile telephone has a low-noise amplifier with transistors for processing signals of very low power, typically on the order of 1 nanowatt to 100 nanowatts. This low-noise amplifier is followed by a mixer for carrying out frequency transposition from a signal output by a voltage-controlled oscillator associated with a phase-locked loop, which receives a signal output by a local oscillator and has a frequency divider.
Typically, the voltage-controlled oscillator processes signals on the order of 100 mvolts while the phase-locked loop processes signals on the order of 200 mvolts and has (in particular for the digital portion) CMOS transistors powered at 3 volts. These signals typically have a power on the order of one watt, which is high when compared with the power of the signals processed by the low-noise amplifier. Therefore, in the substrate, there is high-frequency analog noise associated with the voltage-controlled oscillator, as well as wide-band digital noise associated with the phase-locked loop. The combination of these perturbations creates white noise whose power in decibels is liable to perturb the low-noise amplifier if all of these components are produced within the same integrated circuit.
One current solution for overcoming such problems is to produce the low-noise amplifier, the voltage-controlled oscillator, the phase-locked loop, and the mixer on separate integrated circuits. For example, the low-noise amplifier and the voltage-controlled oscillator can be produced on two separate circuits having gallium arsenide substrates, while the phase-locked loop and the mixer can be produced on a silicon integrated circuit, and more particularly one appropriate to BiCMOS technology (i.e., bipolar CMOS technology in which bipolar transistors are combined with insulated-gate complementary field-effect transistors). However, this solution causes an increase in the overall area of the device overall, and in its cost.
SUMMARY OF THE INVENTION
In view of these drawbacks, it is an object of the present invention to overcome the above-mentioned drawbacks and to provide a noise emitter and a noise-sensitive receiver within the same integrated circuit, while ensuring decoupling between the emitter and the receiver.
Another object of the present invention is to reduce or eliminate the coupling noise that propagates inside the substrate of an integrated circuit.
One embodiment of the present invention provides a semiconductor device of the type having an integrated circuit with connection terminals connected to metal pads by connecting wires. The integrated circuit includes a semiconductor substrate having a lower portion on top of which there is an upper layer that is more heavily doped than the lower portion. A first block and a second block are produced in the upper part of the substrate, and decoupling means are arranged in the vicinity of the first block. The decoupling means include at least one decoupling circuit that is connected to the lower portion of the substrate and to a ground connection pad, and the decoupling circuit has a minimum impedance at a predetermined frequency. In a preferred embodiment, the decoupling circuit includes an inductive-capacitive resonant circuit having a resonant frequency substantially equal to the predetermined frequency.
Another embodiment of the present invention provides a mobile telephone apparatus that includes at least one integrated circuit. The integrated circuit includes a semiconductor substrate having a lower portion on top of which there is an upper layer that is more heavily doped than the lower portion. A first block and a second block are produced in the upper part of the substrate, and decoupling means are arranged in the vicinity of the first block. The decoupling means include at least one decoupling circuit that is connected to the lower portion of the substrate and to a ground connection pad, and the decoupling circuit has a minimum impedance at a predetermined frequency. In one preferred embodiment, the decoupling means includes a plurality of decoupling circuits and each of the decoupling circuits has a minimum impedance at a different predetermined frequency.
Other objects, features, and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration only and various modifications may naturally be performed without deviating from the present invention.
REFERENCES:
patent: 4619001 (1986-10-01), Kane
patent: 5321299 (1994-06-01), Ohkawa et al.
patent: 5519358 (1996-05-01), Tserng
patent: 5734976 (1998-03-01), Bartschi et al.
patent: 5742091 (1998-04-01), Hebert
patent: 5818880 (1998-10-01), Kriz et al.
patent: 5952704 (1999-09-01), Yu et al.
patent: 6072205 (2000-06-01), Yamaguchi et al.
patent: WO 96/37041 (1996-11-01), None
Copeland, M.A., “VLSI for Analog/Digital Communications”, IEEE Communications Magazine, vol. 29, No. 5, May 1, 1991, pp. 25-30, XP000231082.
Burghartz, J.N., et al. “Integrated RF and Microwave Components in BiCMOS Technology”, IEEE Transactions on Electron Devices, vol. 32, No. 9, Sep. 1, 1996, pp. 1559-1580, XP000636271.
Preliminary Search Report dated Aug. 30, 1999 with annex on French Application No. 9815941.
Bongini Stephen C.
Fleit Kain Gibbons Gutman & Bongini P.L.
Galanthay Theodore E.
Meier Stephen D.
STMicroelectronics S.A.
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