Apparatus, system and method of an electrostatically formed nanowire (EFN)

A gas sensor configures to sense at least one predefined type of gas, the gas sensor comprising:

• at least one Electrostatically Formed Nanowire (EFN) comprising:
• a source region;
• at least one drain region;
• a wire region configured to drive a current between the source and drain regions via a conductive channel;
• a first lateral-gate area extending along a first surface of the wire region between said source and drain regions;
• a second lateral-gate area extending along a second surface of the wire region between said source and drain regions;
• and
• a sensing area in an opening in a backside of a silicon substrate under the wire region and the first and second lateral-gate areas, the sensing area configured to, in reaction to a predefined gas, cause a change in a conductivity of the conductive channel;
• and
• a detector to detect the predefined gas based on the current via the conductive channel.