Donor implanted back-gates in GaAs for MBE-grown highest mobility two-dimensional electron systems

Three different elements, Silicon, Selenium, and Tellurium, are ion-implanted in Gallium arsenide to form a conducting layer that serves as back-gate molecular beam epitaxy (MBE) overgrown two-dimensional electron gas (2DEG). While the heavy ion Tellurium creates too many damages gallium layer, both Silicon Selenium show promising results combined with MBE-grown high-quality 2DEGs. Similar 2DEG mobility compared non-implanted reference samples is achieved for implanted structures. Individual contacts challenging. However, structures, annealed before MBE growth, result function back-gate, density of tuned via back-gate.