Three Spartan options for contamination-free wafer sorting

They reduce on-wafer defects and prevent cross-contamination and surface oxidation

Crossing Automation, a US manufacturer of fab and tool automation products, has announced three new options for the Spartan 300 wafer handling product that deliver an end-to-end contamination-free sorter environment.

The new options are aimed at high volume manufacturing at 32nm and below where new levels of contamination control have become a requirement to ensure process performance.

Crossing Automation's environmental controls are said to reduce on-wafer defects, prevent cross-contamination and surface oxidation, as well as reduce required tool maintenance.

“As process nodes shrink, contamination at the molecular level is starting to have an impact on device yield and performance,” said Michael Brain, vice president of marketing at Crossing Automation.

“These issues must be addressed now to ensure that process nodes continue to shrink for 300mm manufacturing. Beyond that, achieving contamination-free manufacturing is critical to enabling the 450mm transition, where particle tolerances will continue to shrink.”

The three new options are the Spartan Enerta environmental purge; the chemical filter option; and the low contact backside end effector.

Using pure, ultra-clean nitrogen, the Spartan Enerta is able to achieve relative humidity below 5% within 85sec for incoming front opening unified pods (FOUPs), making it the fastest N2 purge available in the industry. It protects the wafers from O2 and H2O exposure, preventing native oxide growth and corrosion of copper interconnects while reducing the impact of chemical residue that could react with water vapour and create additional damage. It also reduces the impact of critical timing between process steps by reducing exposure to oxygen and water vapour.

The Spartan Enerta is a combination FOUP nozzle and door purge. The door purge combines a top and side manifold that allows it to maintain purge with the door open and while wafers are moving in and out of the FOUP. Careful gas management and flow control enable a rapid purge while eliminating the particle contamination associated with conventional purging technologies. The system uses advanced recipe-controlled purging that provides complete user control over ramp and flow rates, all under full manufacturing execution system (MES) control.

The chemical filter option addresses the issue of airborne molecular contamination (AMC), which, due to its microscopic size, is able to penetrate standard cleanroom filters. This causes a number of process yield and reliability issues, particularly at the 32nm node and below.

The Spartan low contact backside end effector achieves a level of cleanliness that eliminates backside particles, which are increasingly having an impact on process performance as manufacturing nodes shrink.