Pre-treatment method performed on a semiconductor structure before forming hemi-spherical grains of capacitor storage node

Abstract

A pre-treatment method for improving the growth of hemi-spherical grains (HSGs) on a semiconductor structure by removing etching residue before forming a capacitor storage node having the HSGs. The pre-treatment method includes dry-etching a material layer formed on a surface of a semiconductor substrate to form a storage node pattern on the semiconductor substrate. Multiple ashing sequences are then performed on the semiconductor structure using an etching gas, followed by a stripping step using H,SO,to remove any residue remaining on the semiconductor structure after the multiple ashing sequences. The semiconductor structure is then cleaned with an ammonium peroxide mixture (APM), and HSGs are thereafter grown on capacitor storage nodes of the storage node pattern.