| 摘要 |
<p>PURPOSE:To prevent the generation of cracks and chipping by a method wherein, after etching in a specified direction of a gallium arsenide semiconductor substrate having a (100) face as the surface is performed by using a mask having a stripe type pattern and etching liquid composed of sulfuric acid-hydrogen peroxide-water, the substrate is divided into a plurality of chips. CONSTITUTION:The following GaAs compound semiconductor wafer ia used; the wafer surface is (100), the thickness is 500mum, the egde-end-portion is cut in the length of 16mm, the (011) face is exposed as a reference surface, and the diameter is 4 inches. By using said wafer, an IC pattern of 4mm square chip size is formed. Next, by photolithography art, windows shaped by perpendicularly intersecting parallel lines of 50mum in width are opened in a resist film. The directions of the parallel lines are <001> and <0(-1)0>. <001> is inclined at 45 deg. to <011> which is the direction of the reference surface (011). <0(-1)0) is the direction inclined at 135 deg. to <011>. The wafer is etched by using etching liquid whose composition is H2SO4:H2O2:H2O=1:8:1. Thereby, the same-sized chips wherein the etching surface is perpendicular to the wafer surface can be obtained without cracks and chippings.</p> |
