Semiconductor isolation method utilizing anisotropic etching and differential thermal oxidation

Abstract

Abstract A SEMICONDUCTOR BODY IN WHICH A PLURALITY OF SEMICONDUCTOR DEVICES ARE FORMED. ADJACENT SEMICONDUCTOR DEVICES ARE ISOLATED ONE FROM THE OTHER BY ISOLATION MOATS FORMED BY ANTISOTROPIC ETCHING OF THE SEMICONDUCTOR BODY. THE ISOLATION MOATS ARE OXIDIZED WITH OXIDE GROWING ON THE (111) FACES OF THE MOATS AT A FASTER RATE THAN ON THE (100) BOTTOMS OF THE MOATS. THE OXIDE IS THEN REMOVED WITH A DILUTE ETCH WITH THE ETCH BEING APPLIED JUST LONG ENOUGH TO REMOVE THE OXIDE FROM THE BOTTOM OF THE ISOLATION MOATS WHILE STILL LEAVING SOME OXIDE ON THE SLOPING SIDES IN THE (111) PLANE. AND ISOLATION DIFFUSION IS THEN MADE AT THE BOTTOMS OF THE MOATS WITH THE OXIDE ON THE SIDES OF THE MOAT MASKING AGAINST DIFFUSION THROUGH THE SIDES. AT THE SAME TIME THE ISOLATION DIFFUSION IS MADE DIFFUSIONS REQUIRING THE SAME CONDUCTIVITY TYPE FOR THE SEMICONDUCTOR DEVICES ARE MADE. SUBSEQUENTLY THE SEMICONDUCTOR DEVICES ARE COMPLETED.

Inventors

• 👤 D Allison

Bibliographic Details