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A method for a quantitative charge-control analysis of Si with a Gaussian base-dopant impurity-concentration profile is demonstrated. The summary of the measured and calculated parameters for Gaussian profile is also presented.

Temperature dependencies of basewell surface recombination current of silicon metal-oxide semiconductor (MOS) transistors are examined and are correlated with the Shockley-Read-Hall band-trap thermal recombination kinetics. Theoretical and experimental confirmations show that the peak gate voltage and linewidth of the DCIV curve have temperature dependences that are negligible, while the peak current amplitude has a strong temperature dependence.

Low-frequency conductance voltage (LFGV) analysis of Si/Ge(sub.x)Si(sub.1-x)/Si heterojunction bipolar transistors (HBTs) is a method that gives accurate quantitative values for the important minority-carrier transport factors that are behind transistor performance. It makes possible a detailed analysis of emitter injection efficiency and the current gain and is general. It can be applied to other bipolar transistors based on various materials.

An ancient Grecian temple frieze is described in relation to pre-World War II Germany. The frieze was erected in gratitude to the gods that assisted the Greeks in battle, and a connection is drawn between the gods fighting alongside mortals and Hitler's conviction of divine supremacy. The war is portrayed not as one between good and evil but as a fight between the classes.

The base current relaxation transient following reverse emitter-base (EB) bias stress and its effect on time-to-failure (TTF) determination are studied in self-aligned and nonself-aligned silicon bipolar junction transistors with thermal and deposited base oxide. A quantitative model shows that the transient is caused by a reduction of the stress-generated positive charge trapped in the oxide layer near the emitter-base junction due to holes tunneling from oxide hole traps to silicon band states or SiO2/Si interface traps.

The physical degradation mechanism of silicon bipolar junction transistors at high forward current densities accompanies the hydrogenation and dehydrogenation of the electronic interface traps. These traps are present at the metal-silicide/polycrystalline-silicon and at polycrystalline-silicon/crystalline-silicon emitter contact interfaces. A time-to-failure extrapolation methodology is discussed, which includes device temperature correction due to self-heating at the high stress current densities.

The primary hot holes of the n+/p emitter tunneling current bring about degradation of the common-emitter forward current gain, h(sub F E), of the submicron silicon bipolar transistor at a low reverse emitter base junction applied voltage. The tunnel- and substrate-injected hot electrons initiate the generation of silicon/oxide interface traps, which show identical kinetic dependence. Stress voltages less than 2.4V show degradation of h(sub F E).

A direct-current current-voltage uses gate-controlled parasitic bipolar junction transistor of a metal-oxide-silicon field-effect transistor in a p/n junction isolation well to study the variations of the oxide and interface trap density. The process of interface and oxide traps on oxidized silicon is discussed. The technique is more effective and dependable than many of the traditional alternating current methods for finding fundamental kinetic rates and transistor degradation mechanism.

A current-acceleration method, which uses large punch-through current when collector is shorted to base during stress, measures rapid time-to-failure (TTF) of bipolar junction transistors under low-voltage emitter-base reverse-bias stress. A 100-fold stress-time acceleration is shown for this methodology. The 10-year TTF is easily measured in 100 hrs at low operating voltage without extrapolation.

The bulk lifetime and surface recombination velocity in semi-conductors are determined by a new optical method. The photoluminescence decay is measured as a function of the self absorption under different excitation conditions. The photoluminescence decay for a semi-infinite sample with an arbitrary value are used in the derivation of the closed-form analytical expressions. For the non destructive excitation of the parameters in bulk wafers, the comprehensive method is based on the analytical expressions. The GaAs sample are used to demonstrate and characterize the surface passivation of compound semi-conductors with direct band gap.

A parasitic free formula for lateral bipolar measurements of transport and recombination of semiconductor substrates was modeled. Geometrically derived equations were obtained for the recombination parameters of a lateral bipolar transistor. Bulk and surface recombination measurements were determined by the frequency dependence of the collector current.

A novel nondestructive technique is presented for measuring the bulk lifetime and interface recombination velocity of gallium arsenide thin films. The frequency-domain method employs an analysis of the photoluminescence decay reaction of a thin semiconducting layer. The layer is one of many with different thicknesses in a double-heterostructure. The approach may also be extended to other materials surrounded by interfaces and with varying recombination velocities.

The fin width dependence of negative bias temperature instability (NBTI) of double-gate, fin-based p-type Field Effect Transistors (FinFETs) fabricated on silicon-on-insulator (SOI) wafers was investigated. The NBTI degradation increased as the fin width narrowed. To investigate this phenomenon, simulations of pre-stress conditions were employed to determine any differences in gate oxide field, fin band bending, and electric field profile as a function of the fin width. The simulation results were similar at a given gate stress bias, regardless of the fin width, although the threshold voltage was found to increase with decreasing fin width. Thus, the NBTI fin width dependence could not be explained from the pre-stress conditions. Different physics-based degradation models were evaluated using specific fin-based device structures with different biasing schemes to ascertain an appropriate model that best explains the measured NBTI dependence. A plausible cause is an accumulation of electrons that tunnel from the gate during stress into the floating SOI fin body. As the fin narrows, the sidewall device channel moves in closer proximity to the stored electrons, thereby inducing more band bending at the fin/dielectric interface, resulting in a higher electric field and hole concentration in this region during stress, which leads to more degradation. The data obtained in this work provide direct experimental proof of the effect of electron accumulation on the threshold voltage stability in FinFETs. [ABSTRACT FROM AUTHOR]

We investigate the physical mechanisms of breakdown in 21 Å thick silicon dioxide gate oxides in n-channel and p-channel metal-oxide-semiconductor field-effect transistors. The oxide breakdown investigation is based on the direct measurement of the stress-induced charge trapped in the oxide using the direct-current current-voltage technique. The measurements show several parallel breakdown pathways with different oxide field dependence. Direct correlation was found between the steplike increase in the gate current and the oxide-trapped charge. The results point to the multistep character of the oxide breakdown that includes generation of precursor defects by the injection and trapping of either electrons or holes. The weakened defect (breakdown precursor) bonds may be broken by the applied electric field and temperature leading to generation of a conductive percolation path. Time-to-breakdown model is developed taking into the account the oxide field dependence of the different breakdown mechanisms. [ABSTRACT FROM AUTHOR]

P-type Si, doped heavily, was analyzed for diffusion length, mobility and minority carrier electron lifetime at 296 kelvins, revealing that for Naa is less than or similar to 5 times 10 to the power of 18 per cubic centimeter, mu(n)(pSi) is similar to mu(n)(nSi). In case of raised doping levels mu(n)(pSi)/mu(n)(pSi) is similar to 1 to 2.7. At 77 kelvins, Dn(pSi) is lower than at 296 kelvins, for Naa is similar to 3 times 10 the power of 19 per cubic centimeter. There is a proportionate enhancement of mu(n)(pSi) at 77 kelvins with the enhanced level of doping beyond Naa is greater than 3 times 10 the power of 18 per cubic centimeter.

Presents a study which developed an optical method for measurement of the bulk lifetime and surface recombination velocity in semiconductors. Theoretical analysis; Experimental setup and measurements; Conclusions.