Dry-etching method
AssigneeTokyo Electron Limited
InventorsEtsuo Iijima, Meiki Koh
Life of this patent
Estimating the term…
Abstract
A dry-etching method using an apparatus where a wafer is placed on either of a pair of opposed electrodes provided in an etching chamber, and high-frequency power is supplied to both the opposed electrodes to effect a plasma etching. The plasma etching uses a gas containing at least Cl2 and HBr. Trenches 104a, 104b are formed, as shown in FIG. 1B, in a silicon wafer 101 shown in FIG. 1A through a mask layer such as a nitride silicon layer 103. While adjusting the high-frequency power supplied to the opposed electrode where the wafer is placed, the shape of the sidewalls 105a, 105b of the trenches 104a, 104b is controlled. Thus, the trenches can have desired shapes even if the widths of the trenches are different.
Claims17
A dry etching method for forming trenches of desired profiles in single crystalline silicon through a mask layer, the method comprising the steps of:
- employing an etching apparatus in which a substrate is loaded on either one of a pair of electrodes disposed in an etching chamber and facing each other and high frequency powers are supplied to both of the electrodes to thereby execute plasma etching;
- introducing an etching gas into the etching chamber;
- and
- controlling sidewall profiles of the trenches by adjusting a high frequency power applied to the electrode on which the substrate is mounted.
A dry etching method for forming a trench on a silicon substrate by plasma processing silicon of the silicon substrate by way of introducing a process gas into an airtight processing chamber, the method comprising:
- a first process for conducting a plasma processing by introducing a mixture gas at least containing HBr and N2 as the process gas;
- a second process for conducting a plasma processing to form the trench in the silicon of the silicon substrate;
- and
- a third process for conducting a plasma processing by introducing a mixture gas containing at least HBr and C12 as the process gas.
A dry etching method for forming a trench on a silicon substrate by plasma processing silicon of the silicon substrate by way of introducing a process gas into an airtight processing chamber, the method comprising:
- a process performing an etching to round a boundary between an etching mask and the silicon on a sidewall of the trench before conducting a process for forming the trench in the silicon of the silicon substrate;
- and
- process performing an etching to round a bottom portion of the trench after the completion of the process for forming the trench in the silicon of the silicon substrate.
Dependencies are inferred from the claim text.