Research On The Control System For Excimer Laser Micro Fabrication

MEMS characterized by microform dimension and micromanipulation scope, along with the development of micro technology, becomes a high & new-technology for exploring and rebuilding the world from microstructure. The novel micro fabrication technology of excimer laser LIGA, gives more promise for Micro technology in the 21st century. Especially, in the fabrication process of novel biochip, direct writing technology of excimer laser shows a great superiority, compared with the cutting technology of general CNC machining tool. By using the general jigs for the general tools, it is difficult to get terrifically slow feeding speed, stable machining quality and smart micro profile.The overall frame of the control system on micro fabrication process of excimer laser was analyzed and instituted based on its unique characteristics. Topics on computer interface control technologies are discussed in detail, together with hardware design on control circuit, interpolation algorithm, and control software. All of our efforts are concentrated in one purpose-to establish a CNC system suitable for excimer laser micro fabrication.Based on computer local bus tech., the control circuit, the core of which is Intel 8254 IC was designed. It succeeded in driving xyz spindles, rotatable table and shield plate. As an innovation, the precise control of exeimer laser external trigging was achieved, including external trigging pulse and frequency, which makes possible the linked motion of xyz worktable, laser external trigging, and rotatable table.After analyzing interpolation algorithms used for machining process in detail, the special point-by-point algorithm for micro fabrication process was developed based on excimer laser processing theory. Meantime, the interpolation algorithms of line and arc in 4 quadrants were realized, and the problem of auto crossing quadrants was resolved successfully.The visual interface for control system was achieved, based on WINDOWS and Visual C++6.0, and a G command set for MEMS was designed further; Meanwhile, reading function from CAD data file and auto-machining was achieved successfully.