iPhones are improving every year thanks to an obscure Japanese company

After two decades in development, chipmakers are making a costly bet on a technology that will cram even more transistors onto silicon. Their success may hinge on a little-known company in the suburbs of Tokyo.

Lasertec Corp. is the world’s sole maker of equipment that tests glass squares slightly bigger than a CD case that act as a stencil for chip designs. By shining light through the squares, circuits smaller than the width of a few strands of DNA are imprinted onto silicon wafers in a process called lithography. These templates have to be perfect: even a tiny defect can make every single chip in the batch unusable.

c After years of setbacks, the industry has settled on extreme ultraviolet lithography, which uses plasma as the light source to draw lines smaller than 7 nanometers. That’s the size seen in Apple Inc.’s A12 Bionic chip, featured in the iPhone XS and XR.