New 193-nm bottom anti-reflective coatings

Currently, a reduction in the critical dimension (CD) of integrated circuits is needed. Therefore, 193nm (ArF Excimer laser) optical lithography technology is introduced to manufacture IC in the semiconductor industry. In these circumstances, Bottom Anti-Reflective Coatings (BARCs) for 193nm optical lithography are required for high performance. New spin-on organic 193nm BARC chemistries (chromophore-attached polymers) have been developed with the objective being a commercial product. This paper discusses the development of new spin-on organic 193nm BARC (ARC29A). New 193nm BARC had many useful properties considered important for a successful product. In addition to the control of the reflectivity, new 193 BARC was developed with the purpose of increasing adhesion between photoresist and BARC to restrain pattern collapse at interface. It has been strongly required to restrain pattern collapse recently, because of the continuing demand for decreasing feature size. It was accomplished by optimize polymer structure, increasing the affinity to the photoresist and so on. The development process plan details in the releasing in the day. And in litho performance, new 193nm BARC has good compatibility (photoresist-profile, DOF, EL etc) with various photoresists. At IMEC, 80nm resolution was achieved. The plasma etch rate was about 1.3 times leading 193nm photoresist, using CF4 as etchant.