Method for wet etching of high k thin film at low temperature

A process for manufacturing a gate structure of a MOSFET, said process comprising:

• providing a wafer having said gate structure partially manufactured in that a front-end processing has been completed, whereby said gate includes shallow trench isolation, p-well and n-well regions, a high dielectric film and conductive layer over said gate, a lightly doped source/drain region, and a pair of silicon nitride side-walls on said gate;
• wet etching said high dielectric film to expose said source/drain region, said wet etching performed with a mixture including hydrofluoric acid (HF) and perchloric acid (HClO4);
• doping the source/drain region to obtain a highly doped source/drain region;
• and
• performing a back-end metallization process.

A process for manufacturing a gate structure of a MOSFET, said process comprising:

• providing a wafer having said gate structure partially manufactured in that a front-end processing has been completed, whereby said gate includes shallow trench isolation, p-well and n-well regions, a high dielectric film and conductive layer over said gate, a lightly doped source/drain region, and a pair of silicon nitride side-walls on said gate:
• wet etching said high dielectric film to expose said source/drain region, said wet etching performed with a mixture including hydrofluoric acid (HF) and periodic acid (HIO4);
• doping the source/drain region to obtain a highly doped source/drain region;
• and
• performing a back-end metallization process.

A process for manufacturing a gate structure of a MOSFET, said process comprising:

• providing a wafer having said gate structure partially manufactured in that a front-end processing has been completed, whereby said gate includes shallow trench isolation, p-well and n-well regions, a high dielectric film and conductive layer over said gate, a lightly doped source/drain region, and a pair of silicon nitride side-walls on said gate;
• wet etching said high dielectric film to expose said source/drain region, said wet etching performed with a mixture including hydrofluoric acid (HF) and perbromic acid (HBRO4);
• doping the source/drain region to obtain a highly doped source/drain region;
• and
• performing a back-end metallization process.