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The study is concerned with the luminescence properties of ensembles of semiconductor structures containing organic phthalocyanine molecules with erbium ions as complexing agents. The photoluminescence spectra of the structures of the type of erbium monophthalocyanine, bisphthalocyanine, and triphthalocyanine are recorded. The photoluminescence peaks are detected at the wavelengths 888, 760, and 708 nm (and photon energies 1.4, 1.6, and 1.75 eV) corresponding to electronic transitions within the organic complexes. It is found that, when a metal complexing agent is introduced into the molecular structure of the ligand, the 708 nm luminescence peak becomes unobservable. It is shown that, in the bisphthalocyanine samples, the photoluminescence signal corresponding to transitions from the 4F 9/2 level of erbium ions is enhanced.

The transmittance spectra of erbium phthalocyanine complexes in the mid- and near-infrared wavelength regions are studied. A detailed identification of the transmittance lines is presented for three types of phthalocyanine complexes. Data on the absorption of electromagnetic radiation at the wavelengths around 1.5 μm due to the 4 I 13/2 → 4 I 15/2 intracenter transitions between the levels of the erbium ions incorporated into the samples are obtained. It is found that some of the mid-infrared absorption lines shift when the number of organic ligands is increased by a factor of 2 or 3. It is shown that the absorption coefficient at the wavelengths around 1.5 μm is equal to 27.5, 32.5, and 74 cm−1 for erbium monophthalocyanine, bisphthalocyanine, and triphthalocyanine, respectively.

Semiconductor structures of the type of butyl-substituted erbium monophthalocyanine and triphthalocyanine are studied by Raman spectroscopy. It is shown that, when the sandwich-like structure of the molecule incorporating two complexing atoms between the ligands is considered instead of the planar molecular structure with one ligand and one metal atom, a series of lines appears in the Raman spectrum. In this series, the wave numbers of the lines represent an arithmetic progression with the arithmetical ratio ∼80 cm−1. It is suggested that this feature is due to the larger number of organic molecules per metal atom in the triphthalocyanine complex, and the four Raman peaks at the frequencies 122, 208, 280, and 362 cm−1 are the manifestation of slight out-of-plane vibrations of the phthalocyanine ligands.