Thin‐Film PECVD (Ulvac)

Summary

Plasma enhanced chemical vapor deposition (PECVD) process has very important role for thin‐film transistor‐liquid crystal display (TFT‐LCD) fabrication, enabling the deposition of the semiconductor channel layer and of the gate insulator in TFT array. This chapter discusses the plasma behavior in PECVD, the architecture of PECVD equipment, and thin‐film deposition mechanism. Different types of plasma modes are presently available for PECVD, however, the capacitively coupled plasma (CCP) type is dominantly used because it offers a simpler structure and has good scalability to larger substrate sizes. For PECVD, chamber cleaning is very important because particles can be produced from deposits on the chamber walls. Thin‐film passivation is very important for organic light emiting device (OLED) device manufacturing. The fluorine passivated indium gallium zinc oxide (IGZO) TFT has extended operation temperature, and is also advantageous in achieving high performance and high reliability oxide TFTs.