High-quality fs-laser structured Si in air for optoelectronic applications

Effects of rapid thermal annealing on optical properties of ZnTiO3 thin films

Abstract Rapid thermal annealing (RTA) provides a precise control of the thermal budget, making it a powerful tool for tuning semiconductor properties. In this work, unintentionally doped (001) β-Ga 2 O 3 substrates were subjected to RTA under Ar and O2 ambients, and the resulting surface morphology and chemical states were characterized by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The results reveal pronounced surface thermal decomposition and a significant increase in the near-surface Ga vacancy concentration after RTA in Ar, whereas no obvious changes are observed after RTA in O2.

In the present paper, In2O3 NPs were synthesized by a wet-chemical method, in the absence and presence of the surfactant, and deposited as thin films on silicon substrates. After deposition, the films were subjected to rapid thermal annealing (RTA) at 550 °C, 750 °C, and 900 °C, for 300 s, under an inert atmosphere. The correlation between the morphological, structural, and optical characteristics, the wetting capacity of In2O3 films synthesized under different synthesis conditions, and the influence of the RTA treatment are presented. The vibrations of In-O bonds for In2O3 samples were confirmed using FTIR spectroscopy. Structural analysis shows that In2O3 NPs have a cubic crystalline structure, but with the increase in temperature at 900 °C, diffraction peaks characteristic of the tetragonal phase of indium appear, correlated with a decrease in lattice parameters, as a result of the crystallinity. The morphology of the In2O3 samples was studied by SEM, revealing predominantly spherical and uniformly distributed particles with nanometric sizes. The absorption spectra of the In2O3 NPs showed peaks in the ultraviolet region, and the high energy bandgap value of the In2O3 films varied between 3.28 and 4.33 eV, depending on the samples and RTA treatment. The contact angle measurements of In2O3 films determined the wetting capacity of the surface, reflecting changes in surface morphology and structure induced by the RTA process. The results suggest that In2O3 thin films with spherical nanoparticles, good wettability, and percolation can be used for the development of sensors with increased selectivity and sensitivity.

Strained Si/SiGe heterostructures are key enablers of high‐mobility and long spin‐coherence electron systems, making them essential for cryogenic electronic and spin qubit devices. The strain‐induced conduction band offset in these structures supports the vertical confinement of electrons, enabling the formation of a two‐dimensional electron gas (2DEG), a basic building block for gate‐defined quantum dot devices. However, high‐temperature processes during (Bi)CMOS fabrication, particularly contact formation, can relax the desired strain and thereby degrade electronic performance. In this work, we investigate the combined influence of sequential phosphorus ion implantation and rapid thermal annealing (RTA) on Si 0.67 Ge 0.33 /Si/Si 0.67 Ge 0.33 heterostructures processed in an industry‐standard 200 mm BiCMOS pilot line. By dividing a high‐dose phosphorus implant into multiple lower‐dose steps and optimizing the annealing conditions, we effectively suppress Si–Ge interdiffusion, thereby preserving strain and heterostructure integrity. To enhance homogeneity across the wafer, nickel silicide (NiSi) metallization is applied for contact formation. The resulting Hall bar‐shaped field‐effect transistors (HB‐FETs) exhibit reliable Ohmic behavior and a specific contact resistivity of 7.68 × 10 − 7 Ωcm 2 at 1.5 K. These results demonstrate a scalable, process‐compatible route to forming low‐resistance contacts in strained Si/SiGe heterostructures while maintaining the structural and electronic properties required for quantum device fabrication.

The influence of rapid thermal annealing (RTA) ambients on defect formation and associated electrical characteristics, such as bias‐stress stability of bottom‐gated amorphous indium gallium zinc oxide (a‐IGZO) thin‐film transistors (TFTs) is investigated. Hydrogen incorporation in HfO 2 from thermal atomic layer deposition diffuses into the a‐IGZO channel during RTA, modulating defect states. Devices annealed in nitrogen (N 2 ) exhibit enhanced field‐effect mobility (∼6.75 cm 2 V −1 s −1 ), and near‐zero threshold voltage (∼0.46 V), due to hydrogen interstitials () acting as shallow donors. Annealing in oxygen (O 2 ) promotes oxygen interstitials () formation, leading to intermediate device performance. Under positive bias stress, O 2 ‐annealed and unannealed devices exhibit positive threshold voltage shifts (ΔV th ) of 0.42 and 0.48 V, respectively, originating from electron trapping at acceptor states, while N 2 ‐annealed TFTs exhibit a small negative ΔV th (−0.12 V), attributed to competing mechanisms between electron trapping at and electron emission from ionized . Negative bias stress induces negative ΔV th associated with oxygen vacancy () ionization, pronounced in N 2 ‐annealed devices owing to higher vacancy density. A defect‐state‐based band diagram is proposed to explain the observed electrical behavior in a‐IGZO/HfO 2 TFTs. These findings offer insight into defect modulation strategies for industrially important a‐IGZO transistor stability and performance.

Abstract A series of Mg-doped multilayered hBN films were prepared by atmospheric chemical vapor deposition. Transmission line method measurements were performed using Ti/Ni, Ti/Au, and Ti/Pt ohmic metals. The impact of rapid thermal annealing is investigated at 650, 850, and 1000 ℃, and the measured current increases with each anneal step. The Ti/Pt scheme yields a current of 82 µA, 330 µA, and 1.9 mA after consecutive 650, 850, and 1000 ℃ rapid thermal anneals, respectively. The p-hBN channel current density is 31.6 µA µm -1 for a 10 µm channel spacing at 10 V and is comparable to other p-type two-dimensional semiconductors. For Ti/Ni, Ti/Au, and Ti/Pt, we report a contact resistance of 498.8, 241.7, and 38.3 kΩ µm, respectively, after a 1000 ℃ rapid thermal anneal and a low bulk resistance of 18 mΩ cm. Hall effect analysis confirms that the samples are p-type with an initial sheet carrier density of 5.6×10 11 cm -2 .

Corrigendum to “Investigating the impact of rapid thermal annealing atmosphere on the properties of sputtered SnO thin films with a tellurium capping layer” [Vacuum 247 (2026) 115148

Investigating the impact of rapid thermal annealing atmosphere on the properties of sputtered SnO thin films with a tellurium capping layer

Enhancement of the metal-oxide-semiconductor (MOS) characteristics for a thulium oxynitride (Tm x O y N z ) passivation layer (PL) on 4H-silicon carbide (SiC) was achieved through the development of a dual-stage process. This methodology comprised rapid thermal annealing in a nitrogen (N2) ambient, followed by normal annealing (NA) in a forming gas-oxygen-forming gas (FOF) mixture. Analysis by grazing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS) confirmed the successful formation of the Tm x O y N z PL. The additional RTA step enhanced nitrogen incorporation at the Tm x O y N z /4H-SiC interface, effectively reducing oxygen vacancies (V o). Data from X-ray reflectivity (XRR) and cross-sectional FESEM corroborated these findings, indicating that the accumulation of nitrogen ions facilitated the development of a thinner interfacial SiO2 layer with a thickness of 2.422 nm. Consequently, the electrical properties of the dual-stage annealed Tm x O y N z PL were enhanced with a higher dielectric constant (k = 13.1), lower slow trap density (STD = 4.24 × 1011 cm-2), lower interface trap density (D it), and lower leakage current density (J).

Group-IV GeSn alloys have gained significant attention as an attractive material system for silicon photonics. Thermal annealing provides an efficient route to improve the crystalline quality and overall performance of GeSn layers. Here, we present a comparative study on the effects of rapid thermal annealing (RTA) and microwave annealing (MWA) on GeSn samples grown on Si via Ge buffer layers containing ∼6.3% Sn under a compressive strain of 0.793%. Structural analysis reveals that RTA at ∼380 °C yields a modest strain relaxation of ∼20% and enhanced crystallinity. However, RTA at higher temperatures results in defect generation and a decrease in photoluminescence (PL) emission intensity. In contrast, MWA at a moderate power of ∼900 W achieves a higher strain relaxation of ∼27–28% while preserving both material quality and PL emission. This advantage is attributed to the more localized energy delivery and reduced thermal budget of MWA, which mitigates Sn diffusion and maintains alloy integrity. In addition, theoretical analysis of the strain-dependent band structure and spontaneous emission in GeSn further confirms that increased strain relaxation enhances the direct-gap character and radiative recombination. These findings demonstrate that MWA offers a more robust and scalable post-growth annealing route for optimizing GeSn layers while balancing strain engineering, optical performance, and material stability, thereby advancing the development of high-performance, complementary metal oxide semiconductor-compatible GeSn-based photonic devices.

This study successfully deposited ZnSnO 3 thin films on microelectromechanical systems (MEMS) structures using a co-sputtering technique combining high-power pulsed magnetron sputtering (HiPIMS) and radio-frequency (RF) magnetron sputtering. Amorphous structures were then formed through rapid thermal annealing (RTA) at [Formula: see text]C. The process consumed only approximately 24.4[Formula: see text]mW at an operating temperature of [Formula: see text]C and exhibited stable and uniform thermal control. The sensing film was integrated within the MEMS structure, demonstrating high process compatibility. Structural analysis confirmed the amorphous properties of the film using X-ray diffractometer (XRD) and high-resolution transmission electron microscopy (HRTEM), effectively reducing charge transport impedance and improving electron mobility. X-ray photoelectron spectroscopy (XPS) analysis showed that the annealing process helped increase the lattice oxygen content, further optimizing sensing performance. Gas sensing experiments showed that at a volatile organic compounds (VOCs) concentration of 5 ppm, the sensor achieved a response rate of 41.1%, demonstrating high selectivity for VOCs, a 4[Formula: see text]s response time, and a 7[Formula: see text]s recovery time, exhibiting high sensitivity and fast response characteristics. Furthermore, the response remained consistent across multiple cycles, indicating excellent stability of the sensor.

The on-surface synthesis of porphyrin-nanographene (Por-NG) hybrids enables systematic control of π-electron magnetism in organic materials, yet the spin behavior of these systems remains difficult to predict because the porphyrin core perturbs the graphene lattice. We report the fabrication and electronic characterization of ZnPors fused with two and four [3]triangulene units (i.e. ZnPorT2 and ZnPorT4 , respectively) on Au(111). Rapid thermal annealing maximizes the yield of discrete hybrids by suppressing surface diffusion and unwanted lateral fusion. Scanning tunneling microscopy and spectroscopy, supported by theory, show that both ZnPorT2 and ZnPorT4 exhibit diradical character with an antiferromagnetically coupled ground state. The hybrids undergo interfacial charge transfer to the metallic substrate: ZnPorT2 donates one electron, forming open-shell ZnPorT2 • + , while ZnPorT4 donates two electrons, affording closed-shell ZnPorT4 2+ . Despite this charge transfer, the multireference character of the frontier orbitals remains in ZnPorT2 • + . The results establish an efficient route to complex Por-NG hybrids and clarify how molecular design and interfacial charge transfer shape their magnetic properties, an essential step toward functional magnetic nanoarchitectures.

Deactivation phenomena of highly B-doped SiGe epitaxial films subjected to nanosecond laser annealing followed by rapid thermal annealing

Solar‐driven generation of reactive oxygen species via photocatalytic membranes is a promising technology for the photodegradation of water‐borne pollutants. Here, titanium dioxide (TiO 2 ) ultrathin films (11.9–28.05 nm) were grown on polytetrafluoroethylene (PTFE) and quartz‐fiber filter (QFF) membranes via atomic layer deposition. The as‐deposited (250°C) films were i) furnace annealed (300°C–1100°C) for 1 h or ii) via rapid thermal annealing (300–500°C) for 3 min. The presence of Ti coating onto/into QFF was confirmed, four times more than on PTFE. As‐deposited TiO 2 films on QFF exhibited the crystalline phase of anatase, while no peaks were observed on PTFE. Films annealed on QFF at higher temperatures did not exhibit a mixed anatase‐rutile phase, regardless of thickness. The films on QFF also exhibited significantly higher absorption of ultraviolet light (<400 nm) compared to the films on PTFE, which had limited absorption (<360 nm). Nonstoichiometric TiO 2− x films exhibited broad absorption from ultraviolet to the near infrared. The annealed films on QFF demonstrated high photocatalytic performance of about 88%–94% removal of methyl orange and 90%–97% for tartrazine 85 (compared to films on PTFE with 36% and 18%, respectively). The TiO 2− x films demonstrated improved performance compared to pure anatase TiO 2 , paving the way for improved photocatalytic membrane performance.

From noble metal ion implantation to tailored optical and electrical performance of TiN thin films via rapid thermal annealing

In this paper we investigate three different heterostructures, all based on ZrO2 grown by ALD (atomic layer deposition), and having each thickness in the range 7–20 nm. These are: metal -insulator-semiconductor (MIS) Au/ZrO2/doped Si, and metal -insulator-metal (MIM) Au/ZrO2/Pt/doped Si, Pt/ZrO2/Pt/doped Si. We have measured their current-voltage characteristics at room temperature and their associate ferroelectricity before and after a rapid thermal annealing (RTA) treatment. High performances nanoscale Schottky diodes were obtained after RTA at the ZrO2 thickness of 15 nm. In the case of the MIS diodes the ideality factor was 1.56 and |2Pr| = 20.6 µC/cm2, while in the case of the MIM diodes the best diodes were Pt/ZrO2/Pt/ with an ideality factor of 2.03 and |2Pr| = 47.9 µC/cm2 and a leakage current in the range 10–50 fA. The subthreshold swing of 31.6 mV/decade and an on/off ratio of 107 show that these ZrO2 -based MIM diodes are an excellent candidate for low-power logic applications.

Reliable engineering of low-resistance metal semiconductor (M/S) contacts is critical for advancing indium oxide (In2O3) based semiconductor technologies. As device dimensions shrink to the micrometer regime, minimizing contact resistance becomes essential to ensure channel limited operation rather than contact dominated. In this study, we systematically optimized Ni/In2O3 contacts using mild rapid thermal annealing (RTA) at 250 °C in nitrogen ambient conditions compatible with back-end-of-line (BEOL) processing and evaluated their performance using the transfer line method (TLM). Ni/In2O3 TLM structures were fabricated via photolithography and liftoff, followed by RTA at varying durations. Quantitative TLM analysis demonstrated a substantial reduction in contact resistance (RC) to 6.24 Ω, normalized contact resistance (N · RC) to 1.25×10−1 Ω cm, specific contact resistivity (ρC) to 1.53×10−6 Ω cm2, and a short transfer length (LT) of 123 nm, all achieved without intentional doping or complex metallization. This process driven, BEOL compatible approach provides a robust route to low-resistance contacts in In2O3 thin films, enabling a reliable foundation for next generation low power, high performance oxide electronics.

Pre-curing treatment optimises the grain growth of high-performance Na super ionic conductor-type Na3V2(PO4)3 thin films for sodium-ion batteries.

Effect of rapid thermal annealing on the characteristics of zinc nitride films prepared by radio-frequency magnetron sputtering