The current CMOS (complementary metal oxide semiconductor) technology faces technical and economic difficulty in further miniaturization. Some predict that 1-dimensional structures may be used as alternative functional devices. New device structures may include 3-terminal field-effect, transistors or quantum wells aligned in a 1-dimensional chain. We proposed a method for constructing self-assembled, multiple quantum dots of < 10 nm in a semiconducting carbon nanotube, causing a spatial modulation of the band gap. We explain the limits of the current CMOS logic and suggest possible improvement.