  We report deterministic control over moir\'e superlattice interference
pattern in twisted bilayer graphene by implementing designable device-level
heterostrain with process-induced strain engineering, a widely used technique
in industrial silicon nanofabrication processes. By depositing stressed thin
films onto our twisted bilayer graphene samples, heterostrain magnitude and
strain directionality can be controlled by stressor film force (film stress x
film thickness) and patterned stressor geometry, respectively. We examine
strain and moir\'e interference with Raman spectroscopy through in-plane and
moir\'e-activated phonon mode shifts. Results support systematic C$_{3}$
rotational symmetry breaking and tunable periodicity in moir\'e superlattices
under the application of uniaxial or biaxial heterostrain. Experimental results
are validated by molecular statics simulations and density functional theory
based first principles calculations. This provides a method to not only tune
moir\'e interference without additional twisting, but also allows for a
systematic pathway to explore different van der Waals based moir\'e
superlattice symmetries by deterministic design.
