Evaluation of a novel twin 300 mm furnace concept for high productivity in a pilot production

A 300 mm twin furnace configured as a LPCVD poly reactor and an atmospheric reactor (ATM) is evaluated in a production environment. The selected processes were amorphous silicon at the poly reactor and a 900°C wet oxide at the ATM reactor. A within wafer uniformity of ±0.5% and ±1.3% is achieved, respectively. A defect density of 0.28 adders/cm² is detected in the poly reactor and 0.028 adders/cm² (>0.2 μm) in the ATM reactor. Both processes meet the corresponding 200 mm process specification of a 0.2 μm DRAM production. Slip free processing is demonstrated for the 900°C oxide applying ramp rates below 5°C/min. Careful consideration to the hardware design ensures that it is competitive compared to other furnace suppliers in terms of hardware costs, maintainability and throughput