Feed forward silicide control scheme based on spacer height controlling preclean time

A method, comprising:

• forming field effect transistor gates over a substrate;
• forming spacers on said gates;
• measuring said spacers to determine a measured spacer height;
• conducting a pre-cleaning etch using one of hydrofluoric ethylene glycol, hydrofluoric acid, and buffered hydrofluoric acid, wherein a duration of said pre-cleaning etch is adjusted according to said measured spacer height;
• and
• forming silicide on said substrate and said gates.

A method, comprising:

• forming field effect transistor gates over a substrate;
• forming spacers on said gates;
• measuring said spacers to determine a measured spacer height;
• conducting a pre-cleaning etch, wherein a duration of said pre-cleaning etch is adjusted according to said measured spacer height, and wherein said duration of said pre-cleaning is changed if said measured spacer height deviates from a predetermined height;
• and
• forming silicide on said substrate and said gates.