Separation of a silicon substrate into chips by liquid etching

In this paper we present a technological route for separating a silicon wafer into chips(crystals). The chip includes a MEMS membrane (Si/SiO
₂
/Si
₃
N
₄
) of various diameters (1.0 ÷ 2.4 mm) and has of square shape with a side of 6 mm. The relief of the structure was measured by a non-contact optical profilometer. The horizontal dimensions of the structure were determined by means of a microscope. The etching rate of silicon in plasma (SF
₆
/C
₄
F
₈
), a gas (F
₂
) and a liquid (12% KOH) was determined experimentally. The cassette (apparatus) for separation of wafers on chips was designed and manufactured. This new cassette makes it possible to increase the yield of silicon wafers by dividing them into chips without mechanical contact by replacing cutting tool on a liquid etchant. Also, process cutting by liquid etching reduces energy consumption. New cassette reduces probability of operator error and allows to form chips of various shape.