Low charge-up reactive ion metal etch process

A method for forming a residue free patterned aluminum containing metal layer for semiconductor device applications comprising:

• forming an aluminum containing metal layer upon a semiconductor substrate;
• providing a patterned etch mask over the aluminum containing metal layer, which mask protects portions of the aluminum containing metal layer which are to remain on the semiconductor substrate;
• providing a primary etching of the aluminum containing metal layer exposed through the etch mask through the use of a Magnetically Enhanced Reactive Ion Etch plasma, the primary etching being controlled by a first radio frequency power and a first magnetic field strength of the Magnetically Enhanced Reactive Ion Etch plasma;
• providing a multiplicity of intermediate etching steps of the aluminum containing metal layer exposed through the etch mask by sequentially and independently lowering the first radio frequency power and the first magnetic field strength of the Magnetically Enhanced Reactive Ion Etch plasma to a second radio frequency power and a second magnetic field strength of the Magnetically Enhanced Reactive Ion Etch plasma;
• and
• providing a secondary over-etching of the aluminum containing metal layer exposed through the etch mask at the second radio frequency power and the second magnetic field strength of the Magnetically Enhanced Reactive Ion Etch plasma.

A method for forming a residue free patterned aluminum containing metal layer for semiconductor device applications comprising:

• forming an aluminum containing metal layer upon a semiconductor substrate;
• providing a layered etch mask over the aluminum containing metal layer, which mask protects portions of the aluminum containing metal layer which are to remain on the semiconductor substrate;
• providing a primary etching of the aluminum containing metal layer exposed through the etch mask through the use of an Electron Cyclotron Resonance etch plasma, the primary etching being controlled by a first radio frequency power and a first magnetic field strength of the Electron Cyclotron Resonance etch plasma;
• providing a multiplicity of intermediate etching steps of the aluminum containing metal layer exposed through the etch mask by sequentially and independently lowering the first radio frequency power and the first magnetic field strength of the Electron Cyclotron Resonance etch plasma to a second radio frequency power and a second magnetic field strength of the Electron Cyclotron Resonance etch plasma;
• and
• providing a secondary over-etching of the aluminum containing metal layer exposed through the etch mask at the second radio frequency power and the second magnetic field strength of the Electron Cyclotron Resonance etch plasma.