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Product Briefing Outline: Lam Research has launched the 2300 Motif post-lithography pattern enhancement system that uses a proprietary plasma-assisted process. The new system delivers controlled photoresist hole and space CD shrinks of up to 100nm, creating features as small as 10nm, demonstrating extendibility to the 22nm node and beyond. According to the company, competitive post-lithography pattern enhancement systems are typically limited to shrinks of less than 30nm. The system was developed in collaboration with IMEC.]

Problem: With the semiconductor industry reliant on 193nm ArF lithography, continued scaling has become increasingly problematic and expensive. Post lithography CD etch techniques have assisted in enabling features sizes fabricated smaller than the patterned image. However, feature sizes below 30nm are required for aggressive scaling, which has exceeded existing etch system capabilities.

Solution: To shrink feature sizes, the 2300 Motif deposits a thin film coating on printed photoresist holes and spaces. The film is typically the thickness of the desired feature shrink. Using current lithography and mask technology, the photoresist holes and spaces are printed at a large enough size to optimize exposure latitude and minimize distortion. The shrink process is applied after lithographic patterning to reduce printed features to the desired size prior to etching. After etch, the film deposited by Motif is removed during the photoresist strip step. The film deposited by Motif enhances etch plasma resistance, resulting in reduced line roughening and distortion during pattern shrinking and transfer, providing CD uniformity, typically equivalent to or better than incoming lithography, according to the company. In addition, the Motif process can be tuned for a range of feature sizes in the pattern.

Applications: Wide-range of post-lithography CD etch processes.

Platform: Lam etch tools employ a proprietary TCP technology that couples RF power into a low-pressure gas to produce a partially ionized plasma (electrically excited ionized gas) at low pressures. The source power is supplied by a simple planar coil located at the top of the etch chamber. A separate power supply delivers bias voltage to the lower electrode (wafer) to provide independent control of ion energy, which influences parameters such as selectivity and CD bias.

Availability: June 2007 onwards.