Paper SD-WeA7
Selective Deposition through Organic Blocking Layers

Wednesday, November 12, 2014, 4:20 pm, Room 318

With the ever increasing complexity of lithography and associated patterning techniques, pattern overlay has become a critical limiter for the continued scaling of integrated circuits. Self-alignment of patterns through area selective deposition, or area-selective etch is an attractive way of addressing pattern overlay and edge placement challenges. Inherently, surface-selective deposition techniques are rare in the fields of chemical vapor deposition (CVD) and atomic layer deposition (ALD). This is particularly true for the selective deposition of dielectrics. Tuning the chemical properties of precursors to achieve inherent substrate-dependent selectivity is thus a key enabler. In the face of poor inherent selectivity, using organic layers such as self-assembled monolayers (SAMs) as blocking layers for subsequent CVD and ALD deposition is an attractive way of achieving selective growth and controlling defectivity. In this paper we will present a joint experimental and theoretical investigation (Density Functional Theory based calculations with semi-empirical dispersion correction) aimed at assessing the stability of a variety of SAMs and their ability to block the deposition of a dielectric thin film. Simple line space patterns will be used to assess the defectivity of this approach. The critical parameters to achieve area-selective deposition will be discussed including proper surface pre-treatment, optimization of the SAM deposition through judicious choice of SAM terminal group and carbon chain length, and optimization of the deposition process through ALD precursor choice. Finally, obstacles to making selective deposition processes manufacturable will be discussed.