Improvement Of Photo Resist Remove For The 11μm DRAM Deep Trench Capacitor Process

In the semiconductor wet cleaning, sulfuric acid and hydrogen peroxide mixed system (referred to as SPM) used to resist the removal and cleaning process, which is a more mature process。But the practice was found on the SPM photo-resist removal and cleaning process , which will cause a lot of anomalies. Especially for advanced DRAM technology, when using SPM remove the resist at the bottom of deep trench, resist residue always can be found. This article is based on the practice of production defects, and analyzes the main components ( sulfuric peroxide ) of the mixed system of influence photo resist removal process. through experiments and analysis of various factors on the peroxide concentration of sulfuric acid. According to the current widely used in the production of technology, introduce how to control factors related to the regulation, to be stable and sound effects photo resist removal.This article focused on one better way to remove the resist at the bottom of deep trench during 0.11DRAM capacitor manufacturing process. By the large number of comparative experiments carried out investigation and analysis and use of advanced experimental equipment and devices, Wet bench, high degree of electronic scanning equipment, optical instruments and advanced analysis of defective equipment, to find the causes of defects and deficiencies found to avoid the production. After the hard work ,finally, the concentration of sulfuric peroxide has been confirmed as the key factor of the photo resist remove process in the deep trench. And define two actions for the process optimize, raising the temperature of sulfuric acid pre-eight tank and set on time hydrogen peroxide supply. After the optimize actions taken , production wafers yield get better and none this issue suffer again.