Technique for reducing contaminants in fabrication of semiconductor wafers

A method for reducing contaminants in a reactor chamber, said method comprising steps of:

• etching said reactor chamber with a first dry etch process performed with hydrogen and HCL to remove dopants within said reactor chamber;
• baking said reactor chamber with hydrogen after said step of etching said reactor chamber;
• depositing an undoped silicon layer on at least one surface of said reactor chamber to form a sacrificial silicon layer after said step of baking said reactor chamber;
• removing said sacrificial silicon layer from said at least one surface of said reactor chamber with a second dry etch process performed with HCL.

A method for reducing contaminants in a reactor chamber, said method comprising steps of:

• inserting a wafer in said reactor chamber;
• depositing a doped silicon layer having a first dopant concentration level on said wafer;
• removing said wafer from said reactor chamber;
• etching said reactor chamber;
• baking said reactor chamber;
• depositing an undoped semiconductor layer in said reactor chamber to form a sacrificial semiconductor layer, wherein said undoped semiconductor layer is an undoped silicon layer, wherein said sacrificial semiconductor layer is a sacrificial silicon layer;
• removing said sacrificial semiconductor layer from said reactor chamber;
• re-inserting said wafer in said reactor chamber;
• depositing undoped silicon having a second dopant concentration level on said wafer, wherein said second dopant concentration level is less than said first dopant concentration level.