Analysis of Charge Components Induced by Fowler‐Nordheim Tunnel Injection in Silicon Oxides Prepared by Rapid Thermal Oxidation

Abstract

We have analyzed oxide charging and interface trap generation induced by high-field tunnel injection in thin (200 to 250 A) thermal oxides of silicon prepared using rapid thermal oxidation (RTO). Constant-current Fowler-Nordheim tunnel (FNT) injection was used to stress aluminum gate MOS capacitors and to generate oxide and Si-SiO~ interface trapped charge. Analysis of both the flatband voltage and the gate voltage necessary to maintain constant current aIlows us to separate oxide charge generation from charge generated near and at the Si-SiQ interface. The analysis reveals, in addition to background electron trapping at water-related trapping centers, the trapping of holes near the Si-SiO2 interface as well as the generation of interface charge and anomalous positive charge (APC) near the Si-SiO2 interface. The appearance of these charge components is consistent with a comprehensive model of oxide and interface charging proposed recently by DiMaria and co-workers, ad we make use of this model in discussing the extraction of information on oxide charging from FNT charging curves. In particular, we show that under simplifying assumptions consistent with device processing on a particular oxide, useful information concerning generation of specific charge species can be obtained.

Modeling Hysteresis Phenomena in Nanotube Field-Effect Transistors

“…There is no explicit dependence of the hysteresis on temperature in our presented model, although this dependence is possibly related to the activation energy of the traps. A dependence similar to the one observed in NT FETs with the hysteresis greatly reduced at both low temperature (20 K) and high temperature (500 K) has been explained for MOSFETs invoking the anomalous positive charge [5]- [8]. This effect is also based on a reversible exchange of charge with the channel via a tunnelling mechanism.…”

“…The kinetics law for the trapping of the electrons, a first-order differential equation for [8], is used to calculate the rate of the trapping (4) where is the trap density, is the trapping cross section of the trapping centers, is the tunneling current density, and is the filled trap density (empty traps are assumed to be positive and become neutral when an electron is trapped). The rate of the detrapping process, which corresponds to the hole injection and further recombination with trapped electrons, at the reverse polarity, is given by (5) The constants and in this equation are slightly different as compared to the previous one, as the potential barrier for the holes is higher than for the electrons. We assume that and have the same value and are field independent.…”

Analysis of Current Components Observed by Cyclic Current–Voltage Measurement in Metal-Oxide-Semiconductor Capacitors

“…A procedure to inject electrons into gate oxide using FNT has been described elsewhere. 3) The cyclic I-V technique employed in this work and typical data obtained from the as-grown MOS capacitors are illustrated in Figs discharging cycle, and then the sweep direction was reversed for the charging cycle. The data of Fig.…”

“…The characterizations of border traps had been limited to the calculation of trap density without energy information. [1][2][3] Recently, the cyclic I-V technique was developed to characterize border traps. [4][5][6][7][8] In such experiment, data is typically collected as the I-V curves, [4][5][6][7] and the density of border traps (D bt ) is calculated using…”

Simple method for evaluating process-induced charging damage to the gate oxide of metal-oxide-semiconductor devices

“…[7][8][9] Since the changes of V g during stress are due to charge buildup in the oxide, one can use the V g (t) dependence for extraction of trap parameters. 9,10 This approach, however, needs extensive simulation and curve fitting proce-dures. We propose to simplify and modify it, so it can be applied as a fast and simple technique to quantify plasmainduced charging damage in MOS transistors.…”