Quy trình quang khắc để tạo tranzitor. Gồm các nội dung: 1. Giới thiệu: Là phương pháp để tạo ra các chi tiết có độ chính xác cao, bằng cách chiếu một chùm tia điện tử lên lớp EResist nhạy với chùm tia đó. Đặc biệt là không cần dùng mask và thực hiện được với nhiều vật liệu. Tuy nhiên, phương pháp này khá phức tạp, chậm và tốn kém. 2. Ý tưởng của phương pháp 3. Phủ lớp Eresist 4. Tạo hình bằng chùm tia điện tử 5. Tráng rửa 6. Phún xạ 7. Hòa tan
E-Beam Lithography Group P h u n g Va n T h o n g N g u y e n Va n Tr o n g Tr u o n g L e Va n Content Introduction Basic Idea of E-Beam Lithography E-Resist Spincoating E-Beam Drawing Developing Sputtering Lift-Off Introduction Specialized technology for creating extremely fine patterns Basic: It uses a Beam of Electrons across a surface covered with a eResist film sensitive Atributes: Used with very high resolution patterns No mask necessary like photolithography Can work with variety of materials But it’s complicated, slow and costs many millions of dollars Basic Idea of E-Beam Lithography basic steps: E-Resist Spincoating E-Beam Drawing Developing Sputtering Lift-Off E-Resist Spincoating Resist can be chemically changed under exposure of the E-Beam 2 types: Possitive, Negative One of first materials: Polymetyl Methacrilate(PMMA) E-Resist was spun on the substrate and °C baked at 170-270 E-Beam Drawing E-Beam is formed by a Electron Gun after passing through Acceleration and a lot of and Lens Dose Equation: D= (I*t)/A JSM-840A Cross-section of column Click to edit Master text styles Second level Third level Fourth level Fifth level Scattering when E-Beam penetrate the resist=> Electrons spread away and expose unexpected areas Forward Scattring (): When electrons enter Resist, they scatter in small angle, cause broaden initial Beam Diameter d Effective diameter(nm) Rt 1.5 d f = 0.9( ) Vb f Where Rt Resist thickness(nm) Vb Acceleration voltage(KV) Back Scattering (): As electrons pass through resist and enter substrate, many will undergo large angle scattering events These Electrons may return back in to the resist, causing additional exposure This is called Proximity Effect Developing Dissolve all of exposed resist in a specific sovent, such as 1:3 mixture of MIBK (methyl isobuthyl ketone) and Isopropanol (C3H8O) Sputtering Sputter the desired thickness of metal on the wafer Lift-Off Soak the wafer in pirolidone or acetone to dissolve the remaining Resist Final result: Etching Technology Thankyou