US Patent 11049537 Additive patterning of semiconductor film stacks

One or more embodiments described herein generally relate to patterning semiconductor film stacks. Unlike in conventional embodiments, the film stacks herein are patterned without the need of etching the magnetic tunnel junction (MTJ) stack. Instead, the film stack is etched before the MTJ stack is deposited such that the spin on carbon layer and the anti-reflective coating layer are completely removed and a trench is formed within the dielectric capping layer and the oxide layer. Thereafter, MTJ stacks are deposited on the buffer layer and on the dielectric capping layer. An oxide capping layer is deposited such that it covers the MTJ stacks. An oxide fill layer is deposited over the oxide capping layer and the film stack is polished by chemical mechanical polishing (CMP). The embodiments described herein advantageously result in no damage to the MTJ stacks since etching is not required.