POLY-GATE STRUCTURES MANUFACTURED IN A CLUSTER TOOL

Polysilicon-gate structures were manufactured in a cluster tool, using integrated HF vapor etching to remove native oxide. Particle and meta llic contamination was measured. The structures were evaluated in term s of break-down yield at 12 MV/cm and charge to break-down. The wet ch emical preprocessing appeared to remain an important factor. At the le vel of contamination measured (range 10(10) at/cm2) the E(bd) yield ap peared to be affected by the Cr, Fe and Cu concentration and by the pa rticle level. Reduction of the K and Al concentrations and of the surf ace haze level is vital to achieve high charge to break-down. With int egrated HF vapor etching, higher E(bd) yields can be achieved than wit h ex situ HF dipping.