Improved electrical characteristics of high-k gated MOSFETs with post-growth treatment on interfacial layer

• A post-growth treatment is performed on interfacial layer before high-k deposition.
• The treatment includes an IL desorption and a re-growth process.
• Both effective oxide thickness and simultaneously leakage current are decreased.
• The improvement can be attributed to interfacial layer with less defect.

A post-growth treatment is performed on a chemical oxide interfacial layer (IL) before an atomic layer deposition formed high-k for MOSFETs in this work. The treatment includes an IL desorption with a high temperature annealing and a re-growth process with a H2O2 solution. The effective oxide thickness is scaled down and simultaneously the leakage current is decreased too. The improvement can be attributed to the high temperature desorption and the re-grown IL with fewer oxygen vacancies. In addition, a charge pumping technique is applied for interface and IL analyses. The charge pumping data are consistent with material analysis. The post-growth treatment is a novel approach to form an IL for ALD-formed high-k in MOS devices.

Figure optionsDownload as PowerPoint slide