Solar cells (SC) CdS-CdTe were fabricated by successive deposition of CdS and CdTe layers onto a glass substrate with the area 4 cm<SUP>2</SUP> covered by ITO layer using hot wall transport. CdS layers had the thickness 0.8 - 2.0 micrometers , the resistivity (2.0 - 2.8)*10<SUP>4</SUP>(Omega) *cm and transparency of 65 - 70%. CdTe layers were As doped during growth process and had the resistivity (3 - 7)*10<SUP>5</SUP>(Omega) *cm. At the illumination of CdS-CdTe heterojunctions with an integral light with the intensity of 80 mW/cm<SUP>2</SUP> (AM1.5) the short circuit current is I<SUB>SC</SUB> equals 0.4 - 0.6 mA/cm<SUP>2</SUP> and open circuit voltage is U<SUB>OC</SUB> equals 0.4 V. For to enhance photoelectrical parameters the heterostructures were immersed in CdCl<SUB>2</SUB>:CH<SUB>3</SUB>OH, and then were heat treated in the air. The examination of treatment time and temperature had shown that the optimum temperature is 400 degree(s)C and time interval 40 - 45 min. The illumination of treated structures in the same conditions as non treated had shown that short circuit current reaches I<SUB>SC</SUB> equals 16.8 mA/cm<SUP>2</SUP> and open circuit voltage U<SUB>OC</SUB> equals 0.54 V. The photosensitivity region is also broadening. Homogeneous photosensitivity in the region from 0.5 micrometers to 0.9 micrometers is observed.