Patent ID: 6281068
Filing Date: 2001-08-28
Classification: H01L

Abstract:
Method of forming a buried plate region in a deep trench of a silicon substrate comprising the steps of:a. providing a structure comprised of a silicon substrate coated by a patterned SiO.sub.2 Si.sub.3 N.sub.4 pad layer to define deep trenches formed therein by etching;b. coating the interior walls of said deep trench with a N type doped glass layer and an overlying SiO.sub.2 passivation layer;c. depositing a layer of polymer dispersed in a solvent having high filling/planarizing capability and being RIE etchable to fill said deep trench in excess;d. baking the polymer to evacuate the solvent contained therein to produce a highly planar surface;e. RIE etching the structure to etch the polymer into the deep trench down to the desired depth;f. removing the exposed portion of the N type doped glass layer and overlying SiO.sub.2 passivation layer in said deep trench;g. out-diffusing the N type dopant in said substrate to form the buried plate region; andh. removing the polymer remaining in said deep trench.