A planar waveguide is fabricated by 3 MeV O2+ ion-implanted in MgO-doped lithium niobate, and the refractive index profiles of waveguides are reconstructed based on etching and ellipsometry techniques. The SRIM2003 code is used to simulate the damage distribution induced by implantation. The etching rate versus the etching depth is extracted and the relation between the etching rate and the damage profile is discussed. The index profile of this kind of waveguide is determined by etching in combination with the following ellipsometric measurements. Both ordinary and extraordinary index profiles in waveguide are obtained. The influence of damage profile on index profiles in waveguide, as well as that on waveguide properties is analysed.

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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.

We determined that the use of densification, sacrificial oxidation, gate oxidation and source/drain implantation has the capability to reduce the dislocation. A dislocation-free process is proposed, and its mechanism presented in embedded flash memory. The dislocation decreased when n-type ions were implanted at a low energy level for source and drain. A dry oxidation process using only oxygen without hydrogen and oxidation for logic gates led to the formation of a sacrificial oxide on the rapid thermal oxidation (RTP) methods without densification after gap-filling as reducing dislocation processes. These methods dramatically reduced the standby leakage current.