Decoupling system, method of operating same, and method of fabricating same
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsSzu-Lin Liu, Yi-Hsiang Wang, Jaw-Juinn Horng
Life of this patent
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Abstract
A decoupling capacitance (decap) system which includes: a decap circuit electrically coupled between a first or second reference voltage rail and a first node; and a biasing circuit coupled between the first node and correspondingly the second or first reference voltage rail. Due to the series connection between the decap circuit and the biasing circuit, the voltage drop across the biasing circuit effectively reduces the voltage drop across the decap circuit so that the voltage drop across the decap circuit is less than a voltage drop across the decap system as whole.
Claims20
A decoupling capacitance (decap) system, the decap system comprising:
- a decap circuit and a biasing circuit electrically coupled in a series arrangement, the series arrangement having an unswitched electrical coupling between first and second reference voltage rails;
- the decap circuit being electrically coupled between the first or second reference voltage rail and a first node;
- and
- the biasing circuit being electrically coupled between the first node and correspondingly the second or first reference voltage rail;
- and
- a voltage drop between the first and second reference voltage rails being larger than a voltage drop across the decap circuit;
- the decap circuit including a capacitor-configured metal-oxide-semiconductor field-effect transistor (MOSFET) electrically coupled between the first node and the first or second reference voltage rail;
- a thick-oxide type of MOSFET having a gate oxide thickness greater than about 0.2 nm;
- a thin-oxide type of MOSFET having a gate oxide thickness equal to or less than about 0.2 nm;
- and
- the capacitor-configured MOSFET being a thin-oxide type of MOSFET.
A decoupling capacitance (decap) system, the decap system comprising:
- a decap circuit electrically coupled between a first or second reference voltage rail and a first node;
- and
- a filtered biasing circuit electrically coupled between the first node and correspondingly the second or first reference voltage rail, the filtered biasing circuit including:
- an N-type metal-oxide-semiconductor field-effect transistor (MOSFET) and a P-type MOSFET (PFET) electrically coupled in parallel between the first node and correspondingly the second or first reference voltage rail;
- a first filter electrically coupled to a gate terminal of the N-type MOSFET (NFET);
- and
- a second filter electrically coupled to a gate terminal of the PFET;
- the second filter having a configuration as a high pass filter when the first filter is configured as a high pass filter;
- and
- the second filter having a configuration as a low pass filter when the first filter is configured as a low pass filter.
A method of decoupling from voltage variations in a first voltage drop between first and second reference voltage rails, the method comprising:
- making an unswitched electrical coupling of a series arrangement of components between first and second reference voltage rails, the series arrangement of components including a decoupling capacitance (decap) circuit and a biasing circuit, the making an unswitched coupling of a series arrangement of components including:
- electrically coupling the decap circuit between the first or second reference voltage rail and a first node including,
- configuring a metal-oxide-semiconductor field-effect transistor (MOSFET) as a capacitor (capacitor-configured MOSFET),
- a thick-oxide type of MOSFET having a gate oxide thickness greater than about 0.2 nm,
- a thin-oxide type of MOSFET having a gate oxide thickness equal to or less than about 0.2 nm,
- the configuring including selecting a thin-oxide type of MOSFET to be the capacitor-configured MOSFET, and
- capacitively coupling the first or second reference voltage rail and the first node by electrically coupling the capacitor-configured MOSFET between the first or second reference voltage rail and the first node;
- and
- electrically coupling the biasing circuit between the first node and correspondingly the second or first reference voltage rail resulting in a second voltage drop across the decap circuit which is smaller than the first voltage drop.
Dependencies are inferred from the claim text.