| 摘要 |
<p>PURPOSE:To reduce the overetching and to improve the machining accuracy by using an etching liquid with the number of moles corresponding to the number of moles of a silicon substrate to be eliminated by etching liquid. CONSTITUTION:When anistropic etching of a silicon substrate 1 is performed, a silicon volume Vsi of an etching part 3 to be removed is obtained by Vsi= a X b/2X c. The mole number nsi of the silicon to be eliminated is obtained by nsi=(Vsi X rhosi) X Msi according to the silicon volume Vsi. Therefore, nsi= netch= 1:2= (2X VsiXrhosi/Msi (moles) results. However, netch indicates the number of moles of etching liquid, nsi indicates the number of moles of silicon to be removed, rhosi indicates silicon density, and Msi indicates the amount of atom of silicon. Namely, since silicon and etching liquid react in the ratio of 1:2, use of the etching liquid with the double number of moles that of the moles number nsi of silicon to be removed accurately causes an elimination part 20 along the 111 mode to be etched accurately.</p> |
