AVS 53rd International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS2-TuP

Paper PS2-TuP5
Etching of Ultra-low-k BEOL Material with High Density Plasma

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Etching and Process Integration Poster Session
Presenter: T. Nishizuka, Tokyo Electron, LTD., Japan
Authors: T. Nishizuka, Tokyo Electron, LTD., Japan
T. Nozawa, Tokyo Electron, LTD., Japan
Correspondent: Click to Email
As the design rule of device is evolved, k value of BEOL dielectric material is required to be lower, and its mechanical strength and plasma resistance become also lower. For the current generation whose k is 2.7~3.0, plasma condition of dielectric etching can be still similar to SiO2 etching condition with low plasma density and high ion energy. For the future generation whose k is less than 2.5, however, different plasma condition with high density and low energy is supposed to be applicable since the material become like organic and porous. In this study, we examined RLSA (Radial Line Slot Antenna) microwave plasma to low-k etching, and found extremely low ion energy (RF bias Vpp<250v) resulted in smooth resist mask surface and via sidewall keeping enough etch rate. Furthermore it appeared that the selection of bias power frequency was effective to RIE lag control.