The general dicing process cuts a semiconductor wafer to lengthwise and crosswise direction by using a rotating circular diamond blade. However, inferior goods may be made under the influence of several parameters in dicing process such as blade, wafer, cutting water and cutting conditions. Moreover we can not apply this dicing method to a GaN wafer, because the GaN wafer is harder than other wafers such as SiO$_2$, GaAs, GaAsP, and AlGaAs. In order to overcome this problem, development of a new dicing process and determination of dicing parameters are necessary. This paper describes determination of several parameters - scribing depth, scribing force, scriber inclined angle, scribing speed, and factor for scriber replacement - for a new dicing machine using a scriber.