Growing and determining epitaxial layer thickness

Claim 1

A METHOD FOR CONTROLLING THE THICKNESS OF AN EPITAXIAL FILM COMPRISING THE STEPS OF PREPARING A SUBSTRATE OF A CRYSTALLINE SEMICONDUCTOR MATERIAL, GROWING ON SAID SUBSTRATE AN EPITAXIAL LAYER OF SAID SEMICONDUCTOR MATERIAL HAAVING A RESISTIVITY DIFFERENT FROM THAT OF THE SUBSTRATE, THE SAID EPITAXIAL LAYER BEING OF THE INTERMEDIATE THICKNESS, PLACING SAID SUBSTRATE IN A SAMPLE MOUNT, IRRADIATING SAID SEMICONDUCTOR MATRIAL WITH A SERIES OF MONOCHROMATIC INFRARED BEAMS WHEREBY INTEREFERENCE FRINGES WILL APPEAR DUE TO THHE ESTAABLISHMENT OF AN OPTICAL INTERFACE BETWEEN THE SUBSTRATE AND THE EPITAXIAL LAYER, CALCULATING THE THICKNESS OF SAID FILM FROM THE EQUATION: T=($/2N)P WHERE T IS THE THICKNESS OF THE EPITAXIAL LAYER, $ = THE WAVELENGTH IN FREE SPACE OF THE IMFRARED RATIATIONS, N = THE REFRACTIVE INDEX OF THE EPITAXIAL LAYER AND P = AN INTEGER AND CONTINUING EPITAXIAL GROWTH UNTIL THE DESIRED THICKNESS IS OBTAINED.