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We have studied the effects of proton irradiation on the AlGaN/GaN HEMTs with AlN buffer layer as well as conventional GaN buffer layer. It was found that a short time proton irradiation (~ 50 sec) can promote beneficial effects on device performances, which results in great reduction in the off-state leakage current and the gate leakage current without degrading the output current and transconductance. The pulsed I-V measurement demonstrated that both devices exhibit greatly improved current dispersion characteristics and, particularly, the device with AlN buffer layer shows stronger radiation hardness than that of the device with GaN buffer layer. These interesting results are believed to be due to the hydrogen passivation with thermal annealing effect during the proton irradiation. It is expected that the proper irradiation condition such as fluence, energy, and time is crucial to improve the device performances, rather than to deteriorate the performances.

Charge-trap based resistive switching (RS) has attracted attention in the resistive random-access memory (RRAM) industry due to its gradual RS behavior for multi-level and synaptic applications. In this work, in order to lower the operating current level closely related to device’s degradation, we applied a hydrogen passivation to Zr3N2 based RRAM devices and investigated the correlation between current level and trap density, such as an interface trap density ( $\text{N}_{\mathrm {it}}$ ) at the Zr $_{3}\text{N}_{2}/p$ -Si layer and nitride trap density ( $\text{N}_{\mathrm {nt}}$ ) within Zr3N2 films, for memory cells annealed in conventional N2 gas as well as H2 gas. Compared to the N2-annealed sample, after H2 annealing, $\text{N}_{\mathrm {it}}$ is lowered by the hydrogen passivation effect, which results in a reduction of both current level at high resistive state (HRS) and variation of HRS and low resistive state (LRS). As a result, in the H2 annealed Zr3N2 RRAM cell, we observed a lower operation voltage/current, longer endurance, and larger read margin due to the hydrogen passivation effect.

Several studies have found indications that PV degradation may increase in hotter climates. We show in this paper that degradation does correlate to higher module temperatures, but that these temperatures are significantly affected by the module mounting and. The mechanisms of degradation vary with module technology and quality. Using data from different HIT module installations we were able to extract an activation energy that is consistent with hydrogen passivation layer degradation. In addition, we show that low degradation in hot climates can be achieved for Al-BSF technology if properly installed to reduce heat transfer in order to thermally decouple the modules from the roof. We also found that monofacial and bifacial PERC module degradation is in line with historical degradation rates of Al-BSF.

In this work, the impact of back-end-of-line (BEOL) passivation film deposition on poly-Si 3D NAND device characteristics is investigated. Different interlayer film stacks in BEOL process are found to have significant influence on poly-Si grain boundary traps (GBT) passivation and cell device characteristics. It is considered that BEOL film stacks can influence poly-Si GBT density during subsequent hydrogen passivation process. By optimization of BEOL film stacks, device characteristics are significantly improved.

Al$_{\mathbf {2}} \mathbf {O} _{\mathbf {3}}$/SiN$_{\mathbf {X}}$ passivation stacks have been widely adopted for high-efficiency silicon solar cells. We explored the effects of annealing step procedure and annealing temperature. It was shown that high iVoc were achieved when post annealing treatment performed than pre annealing. The reason for this result was analyzed by ATP images and SIMS profile. Post annealing treatment showed that hydrogen of SiNx migrates to between the silicon surface and Al$_{\mathbf {2}} \mathbf {O} _{\mathbf {3}}$

A new bulk passivation method for multicrystalline-Si using H2S is proposed. It has the added benefit of both hydrogen and sulfur for bulk passivation. Minority carrier lifetime of the samples is measured to monitor the effect of passivation. It is found that sulfur passivation takes place at higher temperatures, ∼100°C higher, than hydrogen passivation, and sulfur passivation results in much higher lifetime gains than hydrogen passivation (2750% vs. 359%). Post-annealing in ambient further improves the lifetime of the samples, which is attributed to improved surface passivation on the p-type samples by Al2O3. The highest lifetime gain achieved is 6750% for H2S passivated samples vs. ∼2400% for forming gas passivated samples. Post-annealing also improves the stability of the increased lifetime.

The objective is to develop better understanding of the optical behavior of a-Si/SiN X multilayer with silicon quantum dots (Si-QDs) which can be used as light absorber material for Si-QD based solar cells. In this work, reflectance of a-Si, SiN X /a-Si, a-Si/SiN X and SiN X /a-Si/SiN X structured films with Si-QDs and without Si-QDs were examined. Hydrogen passivation (H-passivation) of a film with Si-QDs or without Si-QDs showed negligible effect on the optical property of the film. The films with Si-QDs before and after H-passivation showed low reflectance of light in the wavelength range of 200–600 nm compared to the films without Si-QDs. The enhancement in the absorption of light in the films is attributed to the Si-QDs and the quantum confinement effect (QCE).

Numerous studies have shown that the passivation of interface states by hydrogen has a significant impact on degradation mechanisms such as the bias temperature instability (BTI) and hot carrier (HC) degradation. By varying the thickness of the titanium layer at the beginning of the back-end-of-line processing we are able to change the hydrogen content near the Si-SiO2 interface. While the precursor density for negative BTI (NBTI) defects with large time constants, typically observed as a quasi-permanent component, is dramatically increased with the hydrogen passivation degree, the distribution of activation energies is left unchanged. For PBTI, the opposite observation is made, that is, the degradation decreases with hydrogen passivation. Interestingly, the recovery activation energy for hot carrier induced degradation is fully consistent with Pb center passivation, while the recovery of the permanent component of BTI appears to be due to a different mechanism.

Alongside the intensive debate concerning the influence of hydrogen on NBTI we present several details which have received little or no attention in the past. We show experimental evidence that hydrogen does not only passivate interface traps but also positive oxide charges or border traps. Besides passivation, hydrogen increases the overall drift capability of a device under NBTS, thereby increasing the sum of both precursors and activated defects. Furthermore hydrogen passivation has a positive effect on PBTI, presumably through the passivation of pre-existing oxide traps.

The single π−orbital model for graphene has been successful for extended, perfectly flat sheets. However, it cannot model hydrogen passivation, multi-layer structures, or rippled sheets. We address these shortcomings by adding a full complement of d-orbitals to the traditional {s,p} set. To model strain behavior and multi-layer structures we fit scaling exponents and introduce a long-range scaling modulation function. We apply the model to rippled graphene nanoribbons and bi-layer graphene sheets.

In solar cell manufacturing, surface texturing plays an important role in light trapping. Besides optical performance, it was revealed to be also critical to passivation performance of solar cells in this study. Among wafers textured with different chemicals (HNO 3 , KOH and KOH with IPA) and deposited with PECVD SiN x :H films, the acid HNO 3 textured wafers showed the highest bulk lifetime, while the alkaline KOH textured ones showed the lowest surface recombination velocity (SRV). With the advantage of bulk lifetime improvement from acid textured surface, an additional passivation process via the template of acid textured surface prior to KOH or KOH+IPA texturing was testified to be able to enhance bulk lifetime and reduce SRV of wafers. Besides bulk lifetime and SRV, the density of interface trap (D it ) also shows the same correlation with the passivation performance mentioned above, as revealed by CV measurement in this study.

This paper reports metal-organic chemical vapor deposition (MOCVD) growth of undoped and C-doped In x Ga 1−x As 1−y Sb y on (001) InP substrates for the first time. We investigated the relationship between the In x Ga 1−x As 1−y Sb y alloy composition and molar flow ratio of group-III and group-V precursors in both undoped and C-doped In x Ga 1−x As 1−y Sb y and found a characteristic etching effect caused by the decomposition of carbon tetrabromide (CBr 4 ). C-doped InGaAsSb films with high hole concentrations of over 2×1019 cm−3 were obtained for the In composition of less or equal to 0.10. The effect of hydrogen passivation of C-acceptors in C-doped InGaAsSb was negligibly small and similar to that in C-doped GaAsSb.

This paper reports the experimental evidence of anomalous electrical characteristics of large test structures for the characterization of SONOS gate stacks. The anomaly is studied on devices featuring different layout and it is attributed to the property of silicon nitride to block the hydrogen anneal and the passivation of the Si/SiO/sub 2/ interface dangling bonds. Since the hydrogen passivation can occur only from the lateral sides of the device, our findings imply restrictions on the dimensions and on the layout of the test structures used to study the electrical properties of SONOS devices.

The authors report a detailed determination of the structure of damage formed by CH/sub 4/-RIE (reactive ion etching) of InP, using a combination of three different characterization techniques for chemical, physical, and optical properties. X-ray photoelectron spectroscopy (XPS) and Rutherford back scattering (RBS) techniques were employed for the characterization of the chemical and physical structure of the damage. Photoluminescence (PL) measurement was performed at 4.2 K for optical characterization. The results obtained demonstrate the layered structure of the damage and also indicate the recovery of optical damage due to hydrogen passivation and high-temperature annealing. >

Carbon base doping for high performance HBTs promises higher reliability, but the growth techniques must be optimized so that the hydrogen passivation of C acceptors inherent in suitable epitaxial growth techniques does not degrade device performance. Recent results are discussed in this paper.

Despite their best intentions, authors often omit from publications many important technical details. These omissions can lead to contradictions in the literature and inhibit researchers' abilities to duplicate published results. Here, the authors explore "hidden" parameters that are usually not reported, either because they are unknown (e.g., impurity levels) or because they are considered to be of little importance. Specifically, they focus on the effects-and how to reduce the effects-of growth parameters in nearby layers (diffusion), impurities (oxygen) and the cool-down atmosphere (hydrogen passivation).

The design of a machine for semicontinuous production of 100-mm wide silicon ribbons is presented. As the grain selection takes place at the beginning of zone melting, continuous processing instead of single-sheet processing is reasonable and leads to fairly wide grains (on the order of 10-20 mm) extending over the whole length of the ribbon. Grain structure and defects are revealed by etching techniques. Due to the high intragrain defect density there is a significant effect of hydrogen passivation which is demonstrated by EBIC and LBIC measurements. The best solar cells made from silicon sheets from powder (SSP) material showed efficiencies above 13%. >