The Effect of Polysilicon Deposition and Doping Processes on Double-Poly Capacitors - Electrical and AFM Evaluation

AbstractWe have characterized the surface topography of silicon films from different deposition and doping process sequences using AFM and optical reflectivity. The resulting surface structures after deposition, doping, oxide growth, and oxide removal correlate with the electrical leakage currents and breakdown voltages of double polysilicon capacitors. As-deposited amorphous films had smoother surfaces than those deposited in the crystalline state. Gas-phase diffusion doping increases the surface roughness. Only the amorphous in situ doped films retained a smooth surface following oxidation, yielding low leakage capacitors with breakdown fields above 8 MV/cm. Surprisingly, implanted amorphous films exhibited the roughest interfaces, resulting in lower breakdown fields. This study has shown that AFM provides an effective, quick, non-destructive diagnostic technique for semiconductor processing.

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MOCVD HTSC Precursor Delivery Monitored By UV Spectroscopy

MRS Proceedings ◽

10.1557/proc-415-149 ◽

1995 ◽

Vol 415 ◽

Cited By ~ 2

Author(s):

Brian J. Rappoli ◽

William J. DeSisto

Keyword(s):

Gas Phase ◽

Uv Spectroscopy ◽

Diagnostic Technique ◽

Chemical Vapor ◽

Test System ◽

Small Scale ◽

Mocvd Reactor ◽

Phase Concentration ◽

Scale Test

ABSTRACTUV spectroscopy has been used as an in situ diagnostic to measure the gas phase concentration of 2,2,6,6-tetramethyl-3,5-heptanedionate (thd) complexes of Ba, Cu and Y in metalorganic chemical vapor deposition (MOCVD) bubbler effluent. These precursors for MOCVD synthesis of YBa2Cu37−δ (YBCO) show marked instability in gas phase concentration as a function of time during bubbler purge. The UV diagnostic technique has been applied to both a small scale test system and a commercial scale MOCVD reactor.

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Role of boundaries in the crystallization of amorphous films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105199 ◽

1988 ◽

Vol 46 ◽

pp. 626-627

Author(s):

D. A. Smith

Keyword(s):

Low Temperature ◽

Amorphous State ◽

Nucleation And Growth ◽

Amorphous Films ◽

Island Nucleation ◽

Surface Steps ◽

Transmission Electron ◽

Component Systems ◽

Temperature Deposition

The nucleation and growth processes which lead to the formation of a thin film are particularly amenable to investigation by transmission electron microscopy either in situ or subsequent to deposition. In situ studies have enabled the observation of island nucleation and growth, together with addition of atoms to surface steps. This paper is concerned with post-deposition crystallization of amorphous alloys. It will be argued that the processes occurring during low temperature deposition of one component systems are related but the evidence is mainly indirect. Amorphous films result when the deposition conditions such as low temperature or the presence of impurities (intentional or unintentional) preclude the atomic mobility necessary for crystallization. Representative examples of this behavior are CVD silicon grown below about 670°C, metalloids, such as antimony deposited at room temperature, binary alloys or compounds such as Cu-Ag or Cr O2, respectively. Elemental metals are not stable in the amorphous state.

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Gas cylinders. In situ, non-destructive examination and testing of refillable seamless steel tubes of water capacity between 150 L and 3000 L, used for compressed gases Specification

10.3403/30238378u ◽

2015 ◽

Keyword(s):

Steel Tubes ◽

Water Capacity ◽

Seamless Steel Tubes ◽

Gas Cylinders ◽

Non Destructive ◽

Seamless Steel

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COMBINED NANO-COMPUTED TOMOGRAPHY AND X-RAY FLUORESCENCE EXPERIMENTS: A POWERFUL, NON-DESTRUCTIVE TECHNIQUE FOR THE IN-SITU CHEMICAL ANALYSES OF EXTRATERRESTRIAL MATERIALS

10.1130/abs/2018am-324814 ◽

2018 ◽

Author(s):

Manavi Jadhav ◽

◽

Martin Holt ◽

Robert Winarski

Keyword(s):

Computed Tomography ◽

Chemical Analyses ◽

X Ray ◽

Extraterrestrial Materials ◽

Non Destructive

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In Situ Observation of Electron-Beam-Induced Formation of Nano-Structures in PbTe

Nanomaterials ◽

10.3390/nano11010163 ◽

2021 ◽

Vol 11 (1) ◽

pp. 163

Author(s):

Iryna Zelenina ◽

Igor Veremchuk ◽

Yuri Grin ◽

Paul Simon

Keyword(s):

Electron Beam ◽

Gas Phase ◽

Threshold Current ◽

Threshold Current Density ◽

Atomic Scale ◽

In Situ Observation ◽

Nano Structures ◽

Transmission Electron ◽

Initial Crystal

Nano-scaled thermoelectric materials attract significant interest due to their improved physical properties as compared to bulk materials. Well-shaped nanoparticles such as nano-bars and nano-cubes were observed in the known thermoelectric material PbTe. Their extended two-dimensional nano-layer arrangements form directly in situ through electron-beam treatment in the transmission electron microscope. The experiments show the atomistic depletion mechanism of the initial crystal and the recrystallization of PbTe nanoparticles out of the microparticles due to the local atomic-scale transport via the gas phase beyond a threshold current density of the beam.

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Laser-excited elastic guided waves reveal the complex mechanics of nanoporous silicon

Nature Communications ◽

10.1038/s41467-021-23398-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Marc Thelen ◽

Nicolas Bochud ◽

Manuel Brinker ◽

Claire Prada ◽

Patrick Huber

Keyword(s):

Guided Waves ◽

Laser Ultrasonics ◽

Bulk Silicon ◽

Nanoporous Silicon ◽

Stiffness Reduction ◽

Mechanical Characterisation ◽

Isotropic Elasticity ◽

On Chip ◽

Non Destructive

AbstractNanoporosity in silicon leads to completely new functionalities of this mainstream semiconductor. A difficult to assess mechanics has however significantly limited its application in fields ranging from nanofluidics and biosensorics to drug delivery, energy storage and photonics. Here, we present a study on laser-excited elastic guided waves detected contactless and non-destructively in dry and liquid-infused single-crystalline porous silicon. These experiments reveal that the self-organised formation of 100 billions of parallel nanopores per square centimetre cross section results in a nearly isotropic elasticity perpendicular to the pore axes and an 80% effective stiffness reduction, altogether leading to significant deviations from the cubic anisotropy observed in bulk silicon. Our thorough assessment of the wafer-scale mechanics of nanoporous silicon provides the base for predictive applications in robust on-chip devices and evidences that recent breakthroughs in laser ultrasonics open up entirely new frontiers for in-situ, non-destructive mechanical characterisation of dry and liquid-functionalised porous materials.

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Fluorescent in situ hybridization (FISH): A useful diagnostic tool for childhood conjunctival melanoma

European Journal of Ophthalmology ◽

10.1177/11206721211030775 ◽

2021 ◽

pp. 112067212110307

Author(s):

Raquel María Moral ◽

Carlos Monteagudo ◽

Javier Muriel ◽

Lucía Moreno ◽

Ana María Peiró

Keyword(s):

In Situ Hybridization ◽

Fluorescent In Situ Hybridization ◽

Pediatric Population ◽

Diagnostic Technique ◽

Histopathological Diagnosis ◽

Fish Analysis ◽

Conjunctival Melanoma ◽

Adequate Treatment ◽

First Case

Introduction: Conjunctival melanoma is extremely rare in children and has low rates of resolution. Definitive histopathological diagnosis based exclusively on microscopic findings is sometimes difficult. Thus, early diagnosis and adequate treatment are essential to improve clinical outcomes. Clinical case: We present the first case in which the fluorescent in situ hybridization (FISH) diagnostic technique was applied to a 10-year-old boy initially suspected of having amelanotic nevi in his right eye. Based on the 65% of tumor cells with 11q13 (CCND1) copy number gain and 33% with 6p25 (RREB1) gain as measured by the FISH analysis, and on supporting histopathological findings, the diagnosis of conjunctival melanoma could be made. Following a larger re-excision, adjuvant therapy with Mitomycin C (MMC), cryotherapy and an amniotic membrane graft, the patient has remained disease-free during 9 years of long-term follow-up. Case discussion: Every ophthalmologist should remember to consider and not forget the possibility of using FISH analyses during the differential diagnosis of any suspicious conjunctival lesions. Genetic techniques, such as FISH, have led to great advances in the classification of ambiguous lesions. Evidence-based guidelines for diagnosing conjunctival melanoma in the pediatric population are needed to determine the most appropriate strategy for this age group.

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An Atmospheric Origin for HCN-Derived Polymers on Titan

Processes ◽

10.3390/pr9060965 ◽

2021 ◽

Vol 9 (6) ◽

pp. 965

Author(s):

Zoé Perrin ◽

Nathalie Carrasco ◽

Audrey Chatain ◽

Lora Jovanovic ◽

Ludovic Vettier ◽

...

Keyword(s):

Chemical Composition ◽

Gas Phase ◽

Formation Process ◽

Upper Atmosphere ◽

Gas Mixture ◽

Space Probe ◽

Atmospheric Haze ◽

Formation And Evolution ◽

Haze Formation

Titan’s haze is strongly suspected to be an HCN-derived polymer, but despite the first in situ measurements by the ESA-Huygens space probe, its chemical composition and formation process remain largely unknown. To investigate this question, we simulated the atmospheric haze formation process, experimentally. We synthesized analogues of Titan’s haze, named Titan tholins, in an irradiated N2–CH4 gas mixture, mimicking Titan’s upper atmosphere chemistry. HCN was monitored in situ in the gas phase simultaneously with the formation and evolution of the haze particles. We show that HCN is produced as long as the particles are absent, and is then progressively consumed when the particles appear and grow. This work highlights HCN as an effective precursor of Titan’s haze and confirms the HCN-derived polymer nature of the haze.

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