A method of comparing micro-electronic devices. The method includes: placing a first micro-electronic device in a sample chamber of a magnetic resonance imaging machine, subjecting the first micro-electronic device to a magnetic field and a radio frequency pulse, turning off or adjusting the magnetic field and detecting a first returned RF pulse from the first micro-electronic device and storing first data relating to the first returned RF pulse; placing a second micro-electronic device in the sample chamber, subjecting the second micro-electronic device to the magnetic field and the radio frequency pulse, turning off or adjusting the magnetic field and detecting a second returned RF pulse from the second micro-electronic device and storing second data relating to the second returned RF pulse; and comparing the first data to the second data and determining if the second micro-electronic device is essentially identical to the first micro-electronic device based on the comparing.