1nm is one billionth of a meter, not the size of each transistor on the chip, nor the wavelength of the laser light source used to etch the chip to form a circuit, but the width of the wire connection between the transistor and the transistor on the chip, referred to as the line width. The semiconductor industry has traditionally used the process size of line width to represent the level of silicon chip production process. Early connections were made of aluminum, and later copper connections were used.