| 摘要 |
PURPOSE:To improve heat radiation property, and to avoid the thermal fatigue of an adhesive material by a method wherein laminated sections are removed before DI chips are cut from a DI substrate, a supporting region is left only as a polycrystalline semicoductor layer and a plane surface is obtained, and the plane surface is bonded with a support base. CONSTITUTION:Isolation grooves 2 are formed to the upper surface of an n type single crystal silicon wafer 1, a silicon oxide film 3 is shaped onto the upper surface of the grooves, and the supporting region 4 is formed onto the film 3. The supporting region 4 is formed by the section 4a only of a thick polycrystalline silicon layer and the alternately laminated section 4d of thin polycrystalline silicon layers 4b and silicon oxide films 4c. A plurality of n type single crystal silicon island regions 1a are formed through removal by polishing from the lower surface of the wafer 1. An impurity is diffused to each region 1a according to a predetermined pattern, and circuit elements are shaped. The supporting region 4 is removed from the uppermost surface 4e side, and only the polycrystalline silicon layer 4a is left. One parts of the last protective films at each region 1a side are removed through etching, wiring is exposed, and the DI substrate 5 is cut to obtain the DI chips. |
