Surface Detection System For Ultrathin Flexible Integrated Circuit Substrate Of High Density

Flexible Integrated Circuit Substrate(FICS),a branch of Flexible Printed Circuit Board,especially refers to the encapsulated Flexible Printed Circuit Board which can be used to encapsulate the semiconductor chips and components directly on the surface.Due to its flexibility,thin thickness and small in volume,FICS is often applied for connecting chips and electronic components.With the improvement of semiconductor chip manufacturing technology,and the development of electronic products towards the direction of lightweight and portable,FICS also has been developing in the direction of ultra-thin and high density.FICS must be checked weather its surface is acceptable before it's shipped out of the factory.At present,the surface inspection is mainly carried out by automation visual inspection equipment to conduct rough inspection,while the high-density part needs to be examined by the employee under the microscope,which is time consuming and high in labor cost.Therefore,rapid and high precision by means of visual inspection of the detection of FICS is the inevitable trend of industrial development.For this,this article had designed a set of surface detection system for ultra-thin and high density FICS,which optimized the human-computer interaction interface and system operation mode and had performed the research and the algorithms of the image mosaicking and gold surface positioning functions.The main aspects of this article are as follows:(1)In order to meet the requirements of surface detection of FICS before delivery,a set of surface inspection system for ultra-thin and high-density FICS was designed and the hardware model was selected.(2)Combined with the operation of the technical personnel in the process of actual production needs,a simple and easy-to-use software system frame with excellent performance was designed,and the human-computer interface and database operating system were optimized.(3)To optimize the execution efficiency of the system,a fast image capture method was proposed.And according to the characteristics of each task of the system,we designed the multi-thread parallel processing work style and way of synchronization between threads.(4)By analyzing the needs the demand of the system on the function of image mosaicking,comparing the image registration methods based on the feature of key points,the feature of gray of scale information and the feature of transform domain,a multi-resolution image registration method of time-frequency convergence was presented.Through contrast experiment,we found that the method we presented could achieve more rapid and accurate image mosaicking.(5)In view of that feature of the ultra-thin and high-density FICS,a gold surface positioning method based on YUV color space was proposed.Then we transferred its image positioning result to the moving platform coordinate system,which provides convenience for the subsequent high-precision defect detection and realizes the rough inspection and the highprecision inspection of the ultra-thin and high-density FICS.This article provides a reference for the design,method and technology of equipment and system for the surface detection of ultra-thin and high-density FICS.