Abstract: Substrates carrying many molecular devices and circuits made of at least two devices are described. The substrates have less than 50% shorted molecular devices; and molecular circuits comprise a first molecular device and a second molecular device. The first molecular device has at least one self assembled monolayer (SAM) of a first type sandwiched between a first bottom electrode and a first top electrode. Similarly, the second molecular device has at least one SAM of a second type sandwiched between a second bottom electrode and a second top electrode. The first top electrode is electrically connected to the second bottom electrode. In exemplary embodiment, the first and second types of SAM are mutually different.