1st Edition

Photosensitive Polyimides Fundamentals and Applications

By Takashi Yamashita Copyright 1995

    This is the first book to provide an in-depth presentation of photosensitive polyimides for electronic and photonic applications. The authors are leading specialists in this field from Japan, Europe and the U.S.
    From the Preface
    Aromatic polyimides were developed originally as thermostable flexible polymer films for space applications. Now polyimides have found widespread use in the manufacture of electronic devices and have been employed in increasingly diverse areas of electronics and information technology. In addition to their excellent thermal stability and high processability, a wide range of chemical and physical properties provided by molecular engineering makes polyimides highly versatile in the electronics and information industries.
    Lithography of polyimides is an inevitable process in using polyimides for microelectronic fields, and hence increasing research has been devoted to developing photosensitive polyimides, which make it unnecessary to use photoresists for patterning polyimides and diminishing markedly the number of steps in fabrication of various electronic devices.
    In addition, the development of technology of photosensitive polyimides is expected to play a great role in manufacturing photonic devices in the near future, when the design and control of hyper fine structures . . . including higher thermal stability and better processability would be essential.

    Preface

    Introduction to Photopolymers and Microelectronics

    Introduction
    Photosensitive Polymers
    Polymers for Microelectronics
    References


    Applications of Polyimides in Electronics

    Introduction
    Commercially Available Photosensitive Polyimides
    Performance of Commercial Photosensitive Polyimides Applications
    Outlook
    References


    Thermal and Mechanical Properties of Polyimides and Control of High-Order Structures

    Introduction
    Thermal and Mechanical Properties of Aromatic Polyimides
    Control of High-Order Structures of Aromatic Polyimides
    References


    Electronic Configuration of Polyimides and Their Photophysical Processes

    Introduction
    Color of Polyimide Films
    Emission of Polyimide Films
    Photophysical Processes in Polyimide Model Compounds
    Photochemistry of Polyimide Model Compounds
    Other Related Emission Behavior of Imide Compounds and Their Analogue Photoconductivity of Polyimide Films
    References


    Design of Photosensitive Polyimide Precursor Systems

    Introduction
    Structure and Reaction of Photosensitive Polyimide Precursors
    Properties of Polyimides Formed from Photosensitive Polyimide Precursors
    Conclusion
    References


    Intrinsically Photosensitive Polyimides

    Introduction
    Structure and Reaction of Intrinsically Photosensitive Polyimides
    Photoreactivity
    Mechanism and Molecular Design for Improvement of Photosensitive Polyimides References


    Photosensitive Polyimides Based on Chemical Amplification Mechanism

    Introduction
    Amplification Process for Photosensitive Materials
    Chemical Amplification
    Synthesis of Polyimides Characteristics of Protected Polyimides 6F-t-BOC and 6F-THP Lithographic Performance of Protected Polyimides
    Acidolytic Deprotection Rate in Film Matrices
    Photochemical Reaction of PAG in Solid Films
    Properties of 6F-t-BOC and 6F-THP
    References


    Electron Beam Lithography of Polyimides

    Introduction
    Characteristics of Radiation Effects of Polyimides
    Molecular Design of Electron-Beam Sensitive Polyimides
    Mechanism of Electron-Beam Irradiation of Polyimides
    References


    Processing of Polyimides and Related Topics

    Introduction
    Representative Electronic Applications Deposition Methods
    Patterning of Conventional Polyimides Processing of Photosensitive Polyimides
    Processes for High-Density Multilevel Metallization
    References


    Applications of Polyimides to Photonic Devices

    Introduction
    Nonlinear Optical Phenomena
    Organic versus Inorganic Nonlinear Optical Materials
    EO Effect in Polymers and Use for Devices
    Requirements for Polymers in Photonics Polyimide-Based EO Devices
    NLO Chromophore Requirements for Use in EO Polymer Devices
    Photosensitive Polyimides in Photonics Higher Levels of Integration: Advantages of Polymers
    Summary
    References



    39 Tables, 208 Figures
    Numerous tables and graphs provide extensive quantitative data on polyimides for electronic applications. The many schematics and micrographs illustrate materials, processes and devices. Here is a small sampling.
    Tables: Patterning and thermal properties of commercially available photosensitive polyimides
    Mechanical and electrical properties of commercially available photosensitive polyimides
    Chemical structures of commercially available polyimide films
    Required properties of photosensitive poyimides
    Applications of polyimide for electronic devices
    Materials requirements for EO polymer devices

    Micrographs: Memory devices on a silicon wafer, the cell arrays are protected by thick polyimide patterns
    Layout of a liquid crystal display with polyimide alignment layers
    SEM picture of line and space pattern formed with 6F-THP

    Schematics: Chemical principle and processing steps for direct production of PI-patterns
    Polyimide patterning processes
    High temperature post-exposure process using photosensitive polyimide precursors
    Comparison of polyimide patterning processes between polyimides with and without photosensitivity
    Process flow for planarization with lift-off technique
    Examples of applications for polymers in photonic systems

    Biography

    Yamashita, Takashi