Neocera, Inc.

Alfred Benjamin Cawthorne, Iii

Vladimir Vladimirovich Talanov

Antonio Orozco

Nicholas Eric Gagliolo

Nesco Mario Lettsome, Jr

Vladimir V Talanov

Nicolas Eric Gagliolo

Non-destructive localization of open defects in electronic devices is performed with a DC SQUID based RF magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher. RF magnetic fields (or RF current) images are correlated to conductive paths layout of the electronic device, and the open defect is pinpointed at a location of RF current disappearance on the current image. The bandwidth limitations associated with transmission line delays between SQUID circuit and readout electronic, as well as with near-field coupling between different parts of the measurement scheme, are overcome by superimposing the RF flux emanating from device under study on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux. RF readout electronics is based on a double lock-in through sequential demodulation of the RF component of the output SQUID voltage at the modulation flux frequency &#x3c9;and the RF flux frequency &#x3c9;.

Method and system for localization of open defects in electronic devices with a DC squid based RF magnetometer

An RF DC SQUID based magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher is developed which overcomes frequency limitations associated with noise signals due to transmission line delays between the SQUID circuit and readout electronics. The bandwidth limitations are overcome by superimposing the RF flux on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux. RF readout electronics based on a double lock-in technique (sequential demodulation of the RF SQUID voltage at the modulation flux frequency &#x3c9;and the RF flux frequency &#x3c9;), yields a signal proportional to the product of amplitude and phase cosine of RF flux with linear dynamic range up to five orders in magnitude if compared to DC SQUID operated in traditional flux-locked loop regime.

DC SQUID based RF magnetometer operating at a bandwidth of 200 MHz and higher

Growing community of inventors

Franklin, TN, United States of America

Alfred Benjamin Cawthorne, Iii