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The pattern deformation such as photoresist lifting after lithography due to not enough photoresist adhesion to substrate is become critical issue when aspect ratio is much higher than what photoresist adhesion can support. This aspect ratio is getting higher when our design rule of device requests smaller feature size in lithography process. The BARC (Bottom Antireflective Coating), which advanced lithography is using, is very good layer to improve adhesion of photoresist since they are same kind of chemical. However, BARC needs extra etching process before main etching which is step to remove substrate. Sometimes, this BARC etching step generated defects which makes yield loss. Especially, lithography step for metallization with aluminum likes without BARC process to be free from those defect. We think that adhesion of photoresist on metal substrate such as aluminum or TiN is very important to develop lithography process without BARC. The adhesion change between photoresist and metal substrate will be changed as function of how we apply pretreatments for metal substrate. The typical pretreatments before patterning are dry ash, wet cleaning and HMDS treatment.In this paper, we study that adhesion changes as function of pretreatments and their mechanism. To understand the interaction between photoresist and substrate, we analyze surface change of wafers which prepared with several different experimental conditions using XPS (X-ray photoelectron spectroscopy) and Dynamic Contact Angle Analyzer. The results will explain how photoresist adhesion may be changed with different pretreatment conditions and how we can optimize process condition to improve photoresist adhesion without BARC.

Flare has been important variable to obtain good CD control in the resolution limited lithography area such as sub-90 nm node. So far, many papers have been reported about how to measure flare and how flare impact on CD control. And some papers have tried to understand theoretical mechanism of flare.However, we expect that the illumination apertures such as the partial coherence factors or the modified illumination aperture shapes would also give impact on the flare. The short-range flare is changing as the open ratio variation on the mask. We assume that the illumination aperture shape change will also give similar effect as the open ratio variation on the mask.In this paper, we will show how the illumination aperture shapes give effect on short-range flare.Experiments were done for 100 nm lines surrounded by clear window having different width from 1 µm to 20 µm. We utilized the 193 nm scan-and-step exposure tool with the partially coherent conventional and off-axis illuminations apertures. In conclusion, we will prove the relationship between flare and illumination apertures.

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