This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: N.CHEUNG,Sp 2008 EEC243: ADVANCED IC PROCESSING AND LAYOUT Homework Assignment # 9 (Due April 30 , Wed ) Reading Assignment : PDG Chapter 10 PDG Chap 11 [You can skip sections beyond 11.4) Lecture Notes Problem 1 Plasma Processing with RF bias (a) Consider a parallel-plate sputtering chamber. One electrode has an electrically insulating sputtering target with a thickness of 2.5mm which has a target capacitance of ~ 1pF/cm2. If the ion current density is 1 mA/cm2 with a DC applied bias of -1000V, calculate the time required to charge the target capacitance. [ Hint: C = Q/V] (b) The calculated time in part (a) represents a characteristic time for which the target thickness takes up most of the applied bias potential drop [i.e., little voltage drop across the plasma sheath]. This voltage dividing problem can be overcome by we using an RF bias higher than a certain frequency because the ion surface charges can be neutralized by electrons during the negative cycles. Estimate the minimum applied surface charges can be neutralized by electrons during the negative cycles....
View Full Document
This note was uploaded on 11/02/2010 for the course EECS 243 taught by Professor Ee243 during the Spring '03 term at University of California, Berkeley.
- Spring '03