We demonstrate that high quality (111)B oriented heterostructures can be grown in a gas source molecular beam epitaxy system if unity III/V flux ratio, proper substrate temperature, and misoriented substrates are used. We also show piezoelectric modifications of current-voltage characteristics of double barrier resonant tunneling devices by applying uniaxial stresses along certain crystal directions. We found that, under uniaxial, compressive stress parallel to the (110) crystal direction for (001) oriented devices and stress parallel to the (111) direction for (111)B oriented devices, the resonant current peak voltages shift to higher values, and under stress parallel to the (1 (1) over bar 0) direction for (001) oriented devices, the peak voltages shift to lower values. We attribute the asymmetric peak shifts to piezoelectric effects induced by uniaxial stress. Our experimental results are in agreement with calculations.