By Cameron Chai
Novellus Systems has launched its ALTUS Max ExtremeFill process solution to address tungsten fill applications, which require step coverage of more than 100%. The ExtremeFill process is carried out in a novel EFx process module to enhance the present ALTUS Max’ technology and fill capacity.
This allows manufacturers of foundry, logic, and memory chips to manufacture three-dimensional and 2X nm devices. ALTUS ExtremeFill, is presently incorporated in new systems and can be added to existing ALTUS or ALTUS Max systems ensuring reduction in customer cost.
Novellus' conventional chemical vapor deposition (CVD) and tungsten nucleation processes have been able to achieve almost 100 % step coverage for prevailing resistivity and filling needs. However, novel and advanced devices require more than 100% step coverage to enable void-free tungsten fill.
The EFx process module integrates a unique process to contour deposition of tungsten film that provides almost 150% step coverage. This provides total fill of contact structures with overhanging barrier films or re-entrant etch profiles. The ExtremeFill process meets the requirements of existing production technology nodes by allowing 3X nm or greater structures and advanced manufacturing technology nodes with 2X nm or less structures. If the tungsten films are rough, it can create irregular or non-uniform films with empty spaces and huge seam. The ExtremeFill process smoothen the tungsten film, resulting in complete void-free fill.