## 1 Introduction  
Technology products have almost become indispensable in the modern world, as the mobile phone was upgraded to the multi-touch smart phone, the digital photo frame evolved into the tablet PC, the notebook computer evolved into the detachable touch-screen notebook computer, and wearable devices developed into the smart watch. All these consumer electronics products represent extensive applications of touch panels [1]. Panels are divided into touch panels and color filter panels, and many panel processes are identical. The constituent structure is divided into array, cell, and module manufacturing stages. The array process contains thin film, lithography, and etching processes [2]. This study discusses the photolithography process of the array stage. The one glass solution (OGS) of touch panel technology means that the old combination of multiple functional glasses changes into the solution using one single glass touch panel. The difference from the general touch panel is that the OGS structure is combined with the functions of touch control and LENS/Cover Glass. Therefore, the OGS touch panel is more esthetic and stronger than a simple touch panel, and the combination of LENS/Cover Glass can be reduced, such that overall glass thickness decreases a substantial amount. The OGS structure has an artistic black matrix (BM) for display frame printing, shading the backlight, and upgrading the overall texture. The BM produces a BM pattern in the color filter panel process to separate the transmission of color resist. The BM is produced through coating and a negative photoresist. The BM is formed by a photoresist in the OGS panel and is used as a black frame of the OGS touch panel, but it is completed before the capacitive circuit process of the touch panel. The LENS/Cover Glass is then replaced when the BM is done. However, the LENS/Cover Glass uses ink universally, and the general BM for OGS is a negative photoresist, so the production is different from LENS/Cover Glass. After coating, exposure, and development in the BM process, after-develop inspection (ADI) is implemented to check if the appearance is abnormal. The width, opening, and line spacing data after BM photoresist development are measured using optical microscopy (OM), and it is determined whether or not the measured data are within the product specification. In order to use touch control products more conveniently, a general objective is to develop lighter and smaller touch panels. Touch panels using OGS are an important development. The major difference between the OGS touch panel and traditional touch panels is that the artistic appearance and protective function of Cover Glass are integrated into the touch panel, so that the OGS touch panel process can be combined with an artistic appearance. The BM photoresist process influencing the appearance of the OGS touch panel often results in customer complaints about the appearance abnormalities, or in influences on the function. The BM in an OGS touch panel is used as a black frame. The photoresist is divided into positive and negative. The BM photoresist is negative. It is quite difficult to rework the negative photoresist process. If the product exceeds the specification, the product is rejected, and the production expense is wasted. There is still room for improving the BM photoresist process capability \(C_{pk}\) (Appendix A). The photolithography process is an important step, which must be improved to enhance \(C_{pk}\) [3], in order to decrease customer complaint frequency and increase stability. This study proposes an experimental design method for improving the touch panel industry according to lithographic photoresist operating conditions. Related parameters include temperature, exposure, concentration, vacuum pressure, light rays, and humidity. The purpose is to find and master the optimum parameters, establish stable photoresist operating conditions, and enhance the process capability.