Conventional Deep Reactive Ion Etching (DRIE) is a plasma etch process with alternating
half-cycles of 1) Si-etching with SF6 to form gaseous SiFx etch products, and 2) passivation with C4F8
that polymerizes as a protecting fluorocarbon deposit on the sidewalls and bottom of the etched
features. In this work we report on a novel alternative and disruptive technology concept of Spatiallydivided Deep Reactive Ion Etching, S-DRIE, where the process is converted from the time-divided into the spatially divided regime. The spatial division can be accomplished by inert gas bearing ‘curtains’ of heights down to 20 µm. These curtains confine the reactive gases to individual (often linear) injection slots constructed in a gas injector head. By horizontally moving the substrate back and forth under the head one can realize the alternate exposures to the overall cycle.
A second improvement in the spatially divided approach is the replacement of the CVD-based C4F8
passivation steps by ALD-based oxide (e.g. SiO2) deposition cycles. The method can have industrial
potential in cost-effective creation of advanced 3D interconnects (TSVs), MEMS manufacturing and
advanced patterning, e.g., in nanoscale transistor line edge roughness using Atomic Layer Etching.
|Name||IOP Conference Series: Material Science and Engineering|
|Conference||2012 More than Moore: Novel Materials Approaches for Functionalised Silicon Based Microelectronics Symposium|
|Period||14/05/12 → 18/05/12|
|Other||Symposium held at the E-MRS 2012 Spring Meeting|