Plating Systems—Ultra ECP ap

3D ICs with through silicon via (TSV) interconnects and copper plating pillars are the most challenging wafer-level packaging processes you may face as a process engineer. Plating uniform metal films into high aspect ratio, 200µm vias, or uniform copper (Cu) pillars at high plating rates is difficult to achieve with conventional deposition tools. Mass transport limitations reduce the deposition rates, and often result in voids in the TSVs and uneven profiles on Cu pillars.  

Our ECP ap system supports Cu via filling; Cu pillar bumping for Cu; nickel (Ni) and tin-silver (SnAg) plating; solder bumping Ni and SnAg plating; and high-density fan-out (HDFO) WLP products’ warpage wafers, with Cu, Ni, SnAg and gold plating. It delivers high-speed plating technology for uniform deposition in vias and enhances mass transfer of Cu ions during Cu film deposition, coating all pillars on the entire wafer at the same plating rate. You get better uniformity within wafer and within die during high-speed plating, and will achieve wafer-level uniformity below 3%, better coplanarity performance and higher throughput.  

Major Benefits

Cu plating chambers: 

• Separate anode chamber with membrane 
• Soluble Cu anode 
• Anode chamber auto-flush to simplify maintenance 

Sn/Ag plating chambers: 

• Separate anode chamber with membrane 
• Soluble Sn anode 
• Anode chamber auto-flush to simplify maintenance 
• Contact ring plate-out auto-detection 
• Sn++ auto-replenish from anode to cathode 

Ni plating chambers: 

• Separate anode chamber with membrane 
• Soluble Ni anode 
• Anode chamber auto-flush to simplify maintenance 
• In-line temperature control
• In-line rinse heating up to avoid crystallization  

Au plating chambers: 

• Separate anode chamber with membrane 
• Anode chamber auto-flush to simplify maintenance 
• In-line temperature control 

The additives of each electrolyte tank can be dosed automatically, controlled by amperage and/or bath time. Dosing pump and bottle volume are also recorded for timely refilling of the additive bottle. 

Anode auto-flush 

• Faster, better, lower-cost automated anode chamber cleaning 
• Increased uptime 
• Elimination of human disassembly/reassembly errors 
• Reduced chemical exposure, increased safety 

Features & Specifications 

• 8” and 12” wafer compatible 
• Main hardware configuration: 
• 2-3 load ports 
• EFEM with aligner and robot 
• 1 process robot 
• 4 pre-wet chambers, vacuum type 
• 4 cleaning chambers 
• 16-20 plating chambers: Cu, Sn/Ag, Ni 
• Process capabilities: 
• Uniformity: <5% (max-min/2 average) 
• Within-die uniformity: <3% 
• Wafer-to-wafer uniformity: <3% 
• Repeatability: <2% 
• COP: <2.0µm 
• Throughput: 30 wafers/hour (pillar)