Generation of Si dangling bond defects at Si/insulator interfaces induced by oxygen scavenging. Issue 11 (6th October 2014)

• Record Type: Journal Article
• Authors: Cerbu, F.; Nguyen, A. P. D.; Kepa, J.; Afanas'ev, V. V.; Stesmans, A.
• Is Part Of: Physica status solidi. Volume 251:Issue 11(2014:Nov.)
• Page Start: 2193
• Page End: 2196
• Publication Date: 2014-10-06
• Subjects: Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201400066
• Languages: English
• ISSNs: 0370-1972

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <sec id="pssb201400066-sec-0001" sec-type="section"> <p>In this work we analyse the influence of the O‐scavenging process on interface traps in (100)Si/SiO_{<italic>x</italic>}/HfO₂(1.8 nm)/TiN_{<italic>x</italic>}/Si stacks by using electrical measurements and electron spin resonance spectroscopy. The reduction of interfacial SiO_{<italic>x</italic>} by high‐temperature annealing in O‐free ambient is found to lead to severe interface degradation exposed as generation of additional Si dangling bond defects (paramagnetic P_b0 centres). The density of these centres, well known to be electron traps impairing device operation, increases from ∼1 × 10¹² cm⁻² – the value typical for thermally oxidized Si – to &gt;3 × 10¹² cm⁻² upon annealing at 1100 °C. This interface degradation is accompanied by the development of a hysteresis in the MOS capacitance–voltage curves indicating generation of additional oxide traps with areal density in the range of 10¹² cm⁻². However, the trap generation can be alleviated if the O‐scavenging annealing step is performed in helium ambient, suggesting formation of silicon monoxide molecules at the Si/SiO_{<italic>x</italic>} interface as the origin of the observed trap generation.</p> </sec> </abstract>