Hard x-ray photoelectron spectroscopy study of copper formation by metal salt inclusion in a polymer film

Abstract

In this work we present the results of a Hard X-ray Photoelectron Spectroscopy (HAXPES) study on the creation of metallic copper layers via metal-salt infiltration into a poly-2-vinylpyridine (P2VP) film. Metal salt inclusion is a wet chemistry process which allows for the fabrication of both metal and metal oxide films by means of infiltrating a receptive polymer thin film with metal salt precursors. A copper infiltrated P2VP film was subject to UV/Ozone treatment to form copper oxide and annealed in-vacuo to reduce the film to metallic copper. HAXPES and transmission electron microscope (TEM) measurements were used to study the polymer film before and after metal salt infiltration, along with analysis of the copper oxide created after UV/Ozone treatment. The results show successful infiltration of the metal salt into the polymer film, as well as complete conversion to copper oxide following UV/Ozone treatment and reduction to metallic copper with a subsequent in-situ anneal, which demonstrates the ability of the technique for the creation of several key integrated circuit features.

Aluminium oxide formation via atomic layer deposition using a polymer brush mediated selective infiltration approach

“…It is believed that the Al exists in a complex multi -oxidised state at this stage which includes Al -pyridinyl nitrogen bonding [38]. This type of metalpyridine bonding has been observed for the P2VP-OH brush films that have been infiltrated with Cu through a liquid phase infiltration process [13].…”

“…The O 1s spectra in Figure 2 (b) for the P2VP film is made up of two components -the predominant signal at 532.6 eV binding energy represents a combination of C-O bonds in the polymer chain and Si-O bonds (SiO 2 and Si sub oxides) in the layer below. The signal at 531.6 eV binding energy is associated with carbon oxygen bonds that have arisen due to atmospheric exposure [13,40,41]. After ALD deposition, the peak profile of the O 1s significantly broadens.…”

“…Because of the interest in PVP as a potential acceptor, recent work has shown progress in its use via rapid, high-quality grafting of the polymer as a brush layer, and its infiltration with Al through a liquid phase approach [11]. Our previous studies have concentrated on the surface characterisation of these P2VP-OH brushes [12], and the capacity that these films have in facilitating infiltration via a Cu salt (liquid phase) inclusion process [13].…”

A new method for assessing the recyclability of powders within Powder Bed Fusion process

“…Powder particles were deposited on an adhesive carbon pad mounted on a 1 cm 2 diameter steel circular stub. The acquired XPS peaks were curve-fitted to their relevant chemical species using CASAxps [21] and AAnalyser [22], using literature values and the NIST X-ray Photoelectron Spectroscopy Database [23].…”

Precise Definition of a “Monolayer Point” in Polymer Brush Films for Fabricating Highly Coherent TiO2 Thin Films by Vapor-Phase Infiltration

“…The brush was selectively grafted using end groups that bind to site-specific wafer regions. Further, we demonstrated a simple approach for rapid grafting (in seconds) of end functionalized reactive polymer brush films with complete coverage and subsequent conversion to various oxides (Al2O3 55 , Co3O4 56 , CuO 57,58 ) via liquid phase metal ion insertion. Surface deactivation was also achieved using a PS-OH brush that prevents the deposition of ions.…”