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When the frequency, pulse width, the beam profile, and energy density of the laser were controlled, then irradiated onto the silicon wafer with a beam of 15μm diameter or less, we observed that convex dot with a height of 100-300 nano-meters was formed.[1] The laser energy density through which the convex dot was formed was below 3.8J/cm2. In the semiconductor excitation laser, the pulse width was 40nsec-150nsec; the wavelength was 532 nm.[2]We developed equipment by using convex dots that was able to form 2D minute code of 16×16 dots in 100μm ×100μm area in each IC chip on the silicon wafer without particle generation . １．INTRODUCTIONSilicon Wafers were widely used as the original material for semiconductor device production. The ruggedness was made on the surface of the silicon wafer in the semiconductor device formation. The print and etching technology has been repeatedly executed in this process. Generally, the area surrounding the dot is shaved off with etching. Then the dents are made for the convex dot on the surface of the Wafer, and the remaining part becomes a convex dot. This highly accurate process is used for device production [3],[4], [5]. This thesis introduces the technology and equipment that can elevate a microdot for surface shape transformation usage and to mark the ID in any position of the wafer surface with the laser. In general, the laser has been used for the ID formation on the Silicon Wafer and IC chips. The laser removes the surface silicon by ablation and forms a concave hole. The ID gives meaning to the array in the concave hole. Making the semiconductor chip minute has advanced rapidly in recent years and the design rule of wiring has changed from 90nm to 45nm. In addition, the design rule for practical use has become 25nm. It is necessary to avoid metallic pollution or unnecessary particle generation during processing. Any fault in the wiring will become an acute problem in the yield and the function of the LSI chip. Therefore, a variety of pollution evasion measures are adopted in the semiconductor manufacturing process. There is no worry of unnecessary particle generation. The reading performance is improved minutely, and a good method is expected for newly proposed ID technology where the height of a convex dot will have a minimum unit of about 6µm diameter with height of about 300nm[6], [7]. The confirmation for practical use is more progressed now. These convex dots are applied to the wafer ID and IC chip ID. Both of ID writable area of the wafer bevel and IC chip are below 100μm square meter. The micro fabrication technology of the laser can be used together. I will introduce the writing equipment for the wafer the IC chip in this thesis. Moreover, it is discovered to have become a consecutive convex dot if two or more laser beams overlap simultaneously. If 3x3(nine dots) total laser beam is irradiated simultaneously, it becomes a convex dot where uniting a convex dot with the contact point of another convex dot, produces a big project area. Thus, a convex dot can be touched...