Layers of BC x N y were produced in a chemical vapour deposition (CVD) process using trimethylamine borane with He, N 2 , and NH 3 , respectively, as precursor. These layers deposited on Si (100) wafers were characterized chemically by X-ray photoelectron spectroscopy (XPS) and synchrotron radiation-based total reflection X-ray fluorescence analysis combined with near-edge X-ray absorption fine structure spectroscopy (TXRF-NEXAFS). As a result, the composition of the material produced without NH 3 is a B-C bonds containing compound with an atomic relation 1 : 1. Adding NH 3 with a partial pressure of up to about 1.3 Pa the product could be identified as B 2 C 2 N. Increasing the partial pressure of NH 3 to 1.7 and 2.1 Pa the product was enriched in nitrogen yielding a compound characterized as h-BCN. In all cases an impurity of oxygen was observed.

Improvement in the performance of functional nanoscaled devices involves novel materials, more complex structures, and advanced technological processes. The transitions to heavier elements and to thicker layers restrict access to the chemical and physical characterization of the internal material interfaces. Conventional nondestructive characterization techniques such as X-ray photoelectron spectroscopy suffer from sensitivity and quantification restrictions whereas destructive techniques such as ion mass spectrometry may modify the chemical properties of internal interfaces. Thus, novel methods providing sufficient sensitivity, reliable quantification, and high information depths to reveal interfacial parameters are needed for R&D challenges on the nanoscale. Measurement strategies adapted to nanoscaled samples enable the combination of Near-Edge X-ray Absorption Fine Structure and Grazing Incidence X-ray Fluorescence to allow for chemical nanometrology of internal material interfaces. Their validation has been performed at nanolayered model structures consisting of a silicon substrate, a physically vapor deposited Ni metal layer, and, on top, a chemically vapor deposited B(x)C(y)N(z) light element layer.

Triethylamine borane (TEAB) and He, N(2) or NH(3) were applied as additional reaction gases in the production of BC(x)N(y) layers by low-pressure chemical vapor deposition (LPCVD). These layers were deposited on Si(100) wafers and characterized chemically by X-ray photoelectron spectroscopy (XPS) and synchrotron radiation-based total-reflection X-ray fluorescence analysis combined with near-edge X-ray absorption fine-structure spectroscopy (TXRF-NEXAFS). The composition of the material produced without NH(3) was found to be dominated by B-C bonds with the stoichiometric formula B(2)C(3)N. B-N bonds with the formula B(2)CN(3) were preferred when NH(3) was added. A first attempt was made to compare the results obtained by applying trimethylamine borane and TEAB as single-source precursors.

Films of BC(x)N(y) were produced in a plasma-enhanced chemical vapor deposition process using trimethylborazine as precursor and with H2, He, N2, and NH3, respectively, as auxiliary gas. These films deposited on Si(100) wafers or fused quartz glass substrates were characterized chemically by X-ray photoelectron spectroscopy and by synchrotron radiation-based total-reflection X-ray fluorescence combined with near-edge X-ray absorption fine structure. Independent of the auxiliary gas, the B-N bonds are dominating. Furthermore, B-C and N-C bonds were identified. Oxygen, present in the bulk (in contrast to the surface layer of some nanometers, where molecular oxygen and/or water are absorbed) as an impurity, is bonded to boron or to carbon, respectively. The relation of boron and nitrogen changes with the character of the auxiliary gas: cB/cN approximately = 4:3 (for H2 and He) and cB/cN approximately = 1 (for N2 or NH3). Furthermore, physical properties such as the refractive index and the optical band-gap energy were determined.

No abstract