Planarize the sidewall ripples of silicon deep reactive ion etching

In order to diminish the sidewall defects in silicon deep reactive ion etching process, depositing doped silicon dioxide and post-annealing processes are applied. Compared with conventional approaches, the filling-reflow surface shows nearly optical quality. This novel scheme is not restricted to design layout without silicon crystal orientation dependence in the wet chemical etching methods. The unique integrated processes are expected to implement in the micro devices or replica master with optical surfaces