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The performance requirements for ultra-thick photoresists have increased rapidly with the dramatic growth in new lithographic applications that require electroplating processes. Two of the main applications for ultra-thick photoresists are nanotechnology (MEMS) and advanced packaging. Flipchip packaging has become widely adopted to address electrical device performance and chip form factor considerations. The growth in the nanotechnology market is driven by a wide range of products, which include accelerometers, ink jet print heads, biomedical sensors and optical switches.Electroplating levels for these applications require a photosensitive polymer material capable of coating, exposing and plating with conventional semiconductor equipment and standard ancillary process chemicals. A single coat step to achieve the final photoresist thickness is critical to minimize the number of process steps and cycle time. The sidewall profile, aspect ratio, electroplating durability and subsequent stripability of the photoresist are all important. This study characterized a novel positive photoresist (ShinEtsu SIPR 7110M) for the use as a 65 µm thick single coat electroplating level on copper.The lithographic performance of the ultra-thick positive photoresist was optimized using a broad band, low numerical aperture, 1X stepper to control critical dimensions (CD), sidewall angles and aspect ratios. Cross sectional SEM analysis, process linearity, and process latitude plots were used to establish the lithographic capabilities. High aspect ratio structures were then electroplated using the optimized photoresist process to demonstrate photoresist durability and stripability. A recommended process flow is described for this photoresist and stepper.,1752'8&7,21Ultra-thick photoresists are used in many applications including thin film head manufacturing, fluidic chambers, electroforming molds and bump bonding [1]. These areas that can be broadly defined as nanotechnology and advanced packaging. Thin film heads (used for reading and writing data to hard disk drives) and inkjet printheads are the two largest commercial applications of nanotechnology today and are experiencing rapid growth and technological advances. Recently there has been a major acceleration in the

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