Title Page
요약
Abstract
Contents
1. INTRODUCTION 11
2. THEORETICAL BACKGROUND 13
2.1. Definition and classification of etching 13
2.1.1. Wet etching 14
2.1.2. Dry etching 15
2.1.3. Atomic layer etching 19
2.2. Dry etcher 21
2.2.1. Basic structure of dry etching equipment 21
2.2.2. Types and Methods of Dry Etching 22
3. EXPERIMENTAL 27
4. RESULTS AND DISCUSSION 31
5. CONCLUSIONS 45
6. REFERENCES 47
Figure 1. Schematic view of etch profile (a) isotropic etching (b) anisotropic etching 15
Figure 2. Dry etching mechanism 17
Figure 3. Schematic diagram of an ALE process 20
Figure 4. Classification of dry etching according to plasma type 22
Figure 5. Schematic diagram of plasma etching system 23
Figure 6. Schematic diagram of reactive ion etching system. 24
Figure 7. Schematic diagram of inductively coupled plasma etching system. 26
Figure 8. Sequence of Cu thin films etching 27
Figure 9. Schematic of ICP-RIE 28
Figure 10. Schematic diagram of atomic layer etching 30
Figure 11. SEM images of the Cu surfaces masked with SiO₂ exposed to acetylacetone for (a) 15 s and (b) 30 s, the acetylacetone/O₂ gas mixture with a... 32
Figure 12. At% of C,O, and Cu measured by EDS for the Cu layers exposed to the acetylacetone and acetylacetone/O₂ gas mixture, as a function of exposed... 33
Figure 13. XPS narrow scans of (a) Cu 2p, (b) O 1s, and (c) C 1s for the pristine Cu film and the Cu layers exposed to acetylacetone and acetylacetone/O₂ gas mixtures 35
Figure 14. FESEM images of the SiO₂-masked Cu layers physically sputtered by Ar ions at different dc-bias voltages of (a) 100, (b) 150, (c) 200, and (d) 300 V... 38
Figure 15. Etch depths of the cyclic-etched Cu layers obtained by varying the sputtering times at different dc-bias voltages ranging from 100 to 300 V. Etch... 40
Figure 16. FESEM images of the Cu layers etched by the atomic layer etching process. Step1: Exposed process of acetylacetone (40 sccm), Step2:... 42
Figure 17. Etch rate per cycle of the Cu layers and SiO₂ masks, and the etch selectivity as a function of the sputtering time of the Ar ions at the dc... 44