... Equipment . ... At present our UHV equipment consists of two UHV STMs. The first one is a room-temperature STM GPI-300 (atomic resolution on metals) connected with a UHV technological chamber. The chamber is equipped with a sample heater, deposition equipment, tip-clean equipment and a low-temperature 4-probe conduction measurement unit. ... The temperature interval is 5-300 K, the vacuum in the STM chamber is usually better than 10 -10 Torr (typical value 3x10 -11 Torr). ...