Quantitative Estimation of the Metal-Induced Negative Oxide Charge Density in n-Type Silicon Wafers from Measurements of Frequency-Dependent AC Surface Photovoltage

Abstract

The Mario Schenberg gravitational wave detector has been constructed at its site in the Physics Institute of the University of São Paulo as programmed by the Brazilian Graviton Project, under the full support of FAPESP (the São Paulo State Foundation for Research Support). We are preparing it for a first commissioning run of the spherical antenna at 4.2 K with three parametric transducers and an initial target sensitivity of h ∼ 2 × 10 −21 Hz −1/2 in a 60 Hz bandwidth around 3.2 kHz. Here we present the status of this project.PACS numbers: 04.80.Nn, 95.55.Ym

Communication—Anomalous Shift of the Capacitance-Voltage Characteristics Obtained for p-MOS Capacitors with a Tin-Doped Indium Oxide Gate

“…[15][16][17] This charge has the value of (3-6) × 10 11 cm −2 . 16 Using the well known equations for a p-MOS capacitor, 18 the negative charge necessary to obtain a zero threshold voltage for capacitors fabricated on silicon substrates with a donor density of 5 × 10 14 cm −3 and a fixed positive charge of 5 × 10 10 cm −2 at the SiO 2 /Si interface, needs to be 1.5 × 10 11 cm −2 . This value agrees with that reported for Fe or Al contaminated SiO 2 .…”

“…Experimental evidence of negative charge in silicon dioxide grown on n-type silicon surfaces rinsed with RCA alkaline solution contaminated with trivalent (as indium) aluminum or iron is reported in. [15][16][17] This charge has the value of (3-6) × 10 11 cm −2 . 16 Using the well known equations for a p-MOS capacitor, 18 the negative charge necessary to obtain a zero threshold voltage for capacitors fabricated on silicon substrates with a donor density of 5 × 10 14 cm −3 and a fixed positive charge of 5 × 10 10 cm −2 at the SiO 2 /Si interface, needs to be 1.5 × 10 11 cm −2 .…”

Physical and Technological Aspects of Solar Cells Based on Metal Oxide-Silicon Contacts with Induced Surface Inversion Layer

“…oxidized Si wafers soon after they are dipped in an aqueous hydrofluoric acid (HF), and then the charge decreases as the native oxide grows in air. Munakata and Shimizu [9,10] reported that when silicon wafers are rinsed by an SC-1 solution, a fairy large negative charge of 5.8x0 11 charges/cm 2 is observed in commercially available n-type Si wafers. In this case, the wafers were rinsed with the SC-1 solution in a Pyrex glass container.…”

“…The band banding due to this inversion condition is formed at the silicon surface after the chemical treatment using either, SC-1 or hydrogen-peroxide (H 2 O 2 ) solutions, before the ITO film deposition by spray pyrolysis. Based on published data [9,10], the surface potential (diffusion potential) in the n-Si 10 Ω-cm due to acceptor-like surface states can be as high as 0.75 eV how is shown in Figure 2, if the negative charge 8x10 -8 C/cm 2 is located near the silicon surface.…”

Quantitative Estimation of Aluminum-Induced Negative Charge Region Top Area of SiO2 Based on Frequency-Dependent AC Surface Photovoltage

“…2) The metal-induced negative oxide charge has been postulated to be an atomic bridging in the form of an (AlOSi) À network 4) and/or AlO 2 À5) in thermally oxidized Si (SiO 2 ) as well as in native oxide. 6,7) For Al-contaminated and thermally oxidized Si wafers, the behavior of the negative charge dependent on frequency has not been clarified yet. Moreover, Al was found to be segregated at the very top area of the SiO 2 surface, but accurate depth was not investigated.…”