US 6,208,950 B1 · Noise reduction method for a semiconductor device

Abstract

A 1/f noise coefficient characteristic with respect to an operating point of a semiconductor device is measured, and a control voltage corresponding to an operating point of the semiconductor device with which the 1/f noise coefficient is minimized is applied to a MOSFET. Further, using a MOSFET which has known element dimensions, a relationship of a 1/f noise coefficient to a channel area is calculated, and the resistance value of the MOSFET is calculated using the channel width and the channel length as well as a constant peculiar to the MOSFET. Then, the 1/f noise coefficient of the semiconductor device is calculated using the 1/f noise coefficient with respect to the channel area of the MOSFET and the resistance value, and the channel width and the channel length of the MOSFET are set so that the 1/f noise coefficient of the semiconductor device may be minimized.

Claims8

Dependent claims

A noise reduction method for a semiconductor device for suppressing a noise component of a semiconductor device which includes an element having an impedance and a MOSFET circuit which includes at least one MOSFET, comprising the steps of:

measuring a 1/f noise coefficient characteristic indicative of a relationship of a 1/f noise coefficient to an operating point of the semiconductor device using a control voltage to be applied to a gate of the MOSFET as a parameter;
and
applying, based on the 1/f noise coefficient characteristic, a control voltage corresponding to an operating point of the semiconductor device with which the 1/f noise coefficient is minimized within a range within which the MOSFET is operable.

preparing in advance a MOSFET for measurement having a same circuit construction as that of the MOSFET circuit which is composed of a MOSFET having known element dimensions;
calculating a relationship of a 1/f noise coefficient to a channel area of the MOSFET using the MOSFET circuit for measurement;
calculating resistance values of the MOSFET and the MOSFET circuit using a channel width and a channel length presented by the channel area and a peculiar constant of the MOSFET;
calculating a 1/f noise coefficient of the semiconductor device using the 1/f noise coefficient to channel area relationship and the resistance values;
and
setting the channel width and the channel length of the MOSFET to values with which the 1/f noise coefficient of the semiconductor device is minimized.

3 more elements

Dependencies are inferred from the claim text.

Noise reduction method for a semiconductor device

Life of this patent

Noise reduction method for a semiconductor device

Life of this patent

Abstract

Claims8