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Photoemission Threshold Spectroscopy: MOS Band alignments



Nhan V. Nguyen


In this talk I will 1) briefly review SED’s history of the optical thin metrology project, 2) describe the principle of internal photoemission (IPE) and the applications to determine the band alignments of metal-oxide-semiconductor structures, and 3) conclude with a proposal for a new thin film metrology. Over all, the division’s thin film metrology project has evolved to address critical needs along the developments of CMOS technology nodes since late 80’s. It has progressed from the production of SRM’s, the investigation of dielectric thin films used in CMOS to the recent optical property studies of high-k replacement of the traditional silicon dioxide. In the last few years, we have combined IPE with vacuum ultra-violet spectroscopic ellipsometry (VUV-SE) with other physical and chemical complementary characterization techniques to investigate the electronic interfacial properties of alternate channel materials of high mobility channel MOSFET devices. Most of our works have involved collaborations with the IC industry and academia. With the new NIST environment, will expand our measurement capabilities and develop a new wavelength-domain THz spectroscopy to investigate the physical (optical and electrical) properties in the THz region (0.1 THz to 10 THz) for novel semiconductor materials and devices needed to realize future solid state electronics that will enable advances in homeland security, information and communication technology, health care, and earth and space science


Internal Photoemission, Band alignments, ellipsometry, Metal Oxide semiconductor


Nguyen, N. (2011), Photoemission Threshold Spectroscopy: MOS Band alignments (Accessed May 22, 2024)


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Created April 7, 2011, Updated February 19, 2017