In Situ Monitoring of Selective Copper Deposition Processes in a Metal-Organic Chemical Vapor Deposition Using Fourier-Transform Infrared Reflection-Absorption Spectroscopy

Abstract

Vascular and clinical assessments of arterio-venous fistula (AVF) function and access are important in patients undergoing or preparing to undergo renal dialysis. Objective assessment techniques include colour duplex ultrasound and more recently medical infrared thermography. Ideally, these should help assess problems relating to fistula failure or to vascular steal from the hand which can result from excessive fistula blood flow. The clinical value of thermography, as yet, has not been assessed for this patient group. The aims of this study were therefore to investigate the relationships between thermography skin temperature measurement and (a) quantitative ultrasound measurement of AVF blood flow, and (b) qualitative clinical assessment of vascular steal from the hands. Fifteen adult patients underwent thermal imaging of the upper limbs, colour duplex ultrasound to derive AVF blood flow from brachial artery blood flow measurements, and a clinical evaluation for vascular steal. Temperature measurements were extracted from the thermograms, including bilateral arm and hand (Fistula − Non-Fistula) differences, for comparison with derived AVF blood flow and steal grading. Derived AVF blood flow ranged from 30 to 1950 ml min −1 , with a mean rate close to one litre per minute. Thermography detected the warmer superficial veins in proximity to the patent fistulas, with bilateral differences in fistula region skin temperature correlated with derived AVF blood flow (using maximum temperature measurements the correlation was +0.71 [p < 0.01]; and using mean temperature measurements the correlation was +0.56 [p < 0.05]). When thermography measurements were compared with the clinical assessment of steal the mean hand temperature differences separated steal from non-steal patients with an accuracy of greater than 90%. In summary, we have now demonstrated the potential clinical

2-Methyl-1-hexen-3-yne Lewis Base Stabilized β-Diketonate Copper(I) Complexes: X-ray Structures, Theoretical Study, and Low-Temperature Chemical Vapor Deposition of Copper Metal

“…silicon wafers that had preliminary received a 200 nm TiN coat deposited by CVD (thermally with TDMAT and treated with H 2 plasma). As a vacuum break is necessary in our setup, the TiN surface was cleaned with a HF solution to remove any residual oxide . The experiments were performed over a substrate temperature range of 140−300 °C.…”

Surface Kinetics in Copper CVD

“…[25±29] Hence, the surface chemistry in copper deposition from Cu(hfac)-VTMS is expected to resemble that of Cu(hfac) 2 , [25,30] and proposing a mechanism for deposition from Cu(hfac) 2 based on the results from Cu(hfac)VTMS seems reasonable.…”

Preparation of thin copper films from the vapour phase of volatile copper(I) and copper(II) derivatives by the CVD method

“…400,401 In this case, the presence of H 2 during the process [which is usually the case for processes based on Cu(II) derivatives] is an unfavourable factor for the selectivity, as it results in reduction of the SiO 2 surface layer and generation of OH groups. 402 A study of nucleation upon decomposition of (HFA)Cu(VTMS) on a SiO 2 surface `freed' from the OH groups showed that under these conditions, an increase in the flow rate of the starting CCC virtually does not affect selectivity; 403 the pressure in the reactor becomes the main parameter for controlling selectivity.…”