A device and method for forming a vertical channel device is disclosed. The method includes: forming a vertical semiconductor pillar on a substrate, the vertical semiconductor pillar including a first pillar section, a second pillar section and a third pillar section, wherein the second pillar section is arranged between the first pillar section and the third pillar section and wherein the second pillar section is formed of a material being different from a material forming an upper portion of the first pillar section and different from a material forming a lower portion of the third pillar section; forming a spacer layer on a peripheral surface of the upper portion of the first pillar section and on a peripheral surface of the lower portion of the third pillar section; and forming a gate stack embedding the second pillar section and said upper portion of the first pillar section and said lower portion of the third pillar section, wherein the spacer layer forms a spacer between the gate stack and said upper portion of the first pillar section and between the gate stack and said lower portion of the third pillar section.