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* in DRAM memory circuits, capacitor trenches may be 10–20 µm deep,
* in MEMS, DRIE is used for anything from a few micrometers to 0.5 mm.
What distinguishes DRIE from RIE is etch depth: Practical etch depths for RIE (as used in [[integrated circuit|IC]] manufacturing)would be limited to around 10µm at a rate up to 1µm/min, while DRIE can etch
DRIE of glass requires high plasma power, which makes it difficult to find suitable mask materials for truly deep etching. Polysilicon and nickel are used for 10–50 µm etched depths. In DRIE of polymers, Bosch process with alternating steps of SF<sub>6</sub> etching and C<sub>4</sub>F<sub>8</sub> passivation take place. Metal masks can be used however are expensive to use in that several additional photo and deposition steps are always required. Metal masks are not necessary however on various substrates (Si [up to 800 µm], InP [up to 40 µm] or glass [up to 12 µm]) if using chemically amplified negative resists from providers such as Futurrex, Inc. or others.
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