ISSN 1063-7850, Technical Physics Letters, 2012, Vol. 38, No. 6, pp. 572–575. © Pleiades Publishing, Ltd., 2012. Original Russian Text © D.N. Bratashov, S.A. Klimova, A.A. Serdobintsev, I.V. Malyar, S.V. Stetsyura, 2012, published in Pis’ma v Zhurnal Tekhnicheskoi Fiziki, 2012, Vol. 38, No. 12, pp. 45–52. 572 There is a topical technological problem of con- trolling the local properties of semiconductor films, on which it is necessary to create submicron regions with preset physicochemical properties of the surface layer. This task is important, in particular, for the creation of biochips with various functional groups grafted in cer- tain regions of the sensitive surface [1, 2]. One possible way to solve this problem is via the controlled creation of an appropriate topological and potential relief on a semiconductor surface by means of local laser anneal- ing. The mechanisms and consequences of high- intensity laser beam action on semiconductors have been studied for a long time [3], and it has been estab- lished that the results of this treatment can strongly vary, depending on the character of semiconductors and parameters of laser irradiation. The present Letter reports on the possibility of cre- ating local surface regions with preset properties on a micron-precise scale by means of rapid phase transi- tions induced via laser beam in photosensitive semi- conductor films of CdS x Se 1– x solid solutions with thicknesses up to about 1 μm. The sample films were prepared by thermal deposi- tion in vacuum using a charge containing 45 wt % CdS, 55 wt % CdSe, and a doping additive of 0.1 wt % CuCl 2 . The substrates were made of polished glass with a surface roughness not exceeding 12 nm. As is known, CdS and CdSe components form a continuous series of solid solutions, which makes it possible to obtain fine-grained films with homogeneous grain size distri- bution and uniform composition. In addition, the presence of CdSe decreases the melting and sublima- tion temperatures of the mixture as compared to those of pure CdS. The experiments were performed in an Ntegra Spectra scanning-probe microscope (NT-MDT, Zelenograd). The surface relief was studied by atomic force microscopy (AFM) in a tapping mode using an NSG01 (NT-MDT) silicon cantilever. The samples were processed using a solid-state laser operating at 473 nm with a maximum power of 35 mW in the objec- tive focus plane. At a laser beam spot diameter of 0.7 μm in the focus of a 100x/0.90 M plan FLN objec- tive of an Olympus LX-71 microscope, the maximum radiation power density in the incident beam was about 140 mW/μm 2 in a continuous irradiation regime. The radiation power in the course of investiga- tions could be varied in a range of 35 μW–345 mW (accurate to within 10%) using a controlled neutral optical filter. Simultaneously with the laser annealing process, it was possible to measure the photolumines- cence (PL) spectra of samples, which allowed changes in their properties to be monitored in situ. The PL spectra were measured by a Solar-TII spectrometer incorporated in the Ntegra Spectra instrument. For the given laser, the PL spectra were recorded in a 480– 1050 nm wavelength range. Figure 1 shows variations of the PL spectrum of a sample film in the course of laser annealing. The spec- tra were measured in the following sequence. First, the PL spectrum was measured at a minimum laser power (curve 1); then, the measurements were performed for the increasing laser power (curves 2–5). Upon reach- ing the maximum power level (Fig. 1, curve 5), at which the position of the PL intensity maximum exhibited a jumplike change, the laser power was grad- ually decreased to minimum and the corresponding spectra (curves 6–8) were recorded. Each PL spec- trum was measured for 36 ms. As can be seen from Fig. 1, the PL peak is initially observed at 612 nm, which corresponds to interband transitions in a cubic modification of unannealed CdS 0.57 Se 0.43 solid solution and agrees with the initial charge composition (see table) [4, 5]. As the laser radi- Creating Micron Regions with Modified Luminescent Properties and Topology on CdS x Se 1– x Films by Laser Annealing D. N. Bratashov, S. A. Klimova, A. A. Serdobintsev, I. V. Malyar, and S. V. Stetsyura* Saratov State University, Saratov, 410012 Russia *e-mail: stetsyurasv@mail.ru Received February 20, 2012 Abstract—Laser annealing of thin polycrystalline films of CdS x Se 1– x solid solutions has a threshold charac- ter, modifies the local topological relief, and produces a jumplike change in the luminescent properties of the material in the processed region. The possibility of creating local regions with sharply modified physical prop- erties on a micron-precise scale makes the proposed technique a promising tool for the production of semi- conductor sensor chips. DOI: 10.1134/S106378501206020X