Plasma etching method

Patent metadata

Field	Value
Publication number	US-9978566-B2
Application number	US-201615288205-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 9, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

Disclosed is a plasma etching method which is performed using a plasma processing apparatus that is a capacitively coupled plasma processing apparatus, and includes: a processing container; a gas supply unit that supply an etching processing gas into the processing container; a placing table including a lower electrode; an upper electrode provided above the placing table; and a plurality of electromagnets including a plurality of coils, or a plurality of electromagnets each including a coil, on the upper electrode. The plasma etching method includes generating plasma of the processing gas to perform a plasma etching on a single film of a workpiece placed on the placing table; and controlling a current supplied to the plurality of electromagnet to change a distribution of an etching rate of the single film in the diametric direction with respect to the central axis during the generating of the plasma of the processing gas.

First claim

What is claimed is:

1. A plasma etching method which is performed using a plasma processing apparatus that is a capacitively coupled plasma processing apparatus, the plasma processing apparatus comprising:
a processing container;
a gas supply unit configured to supply an etching processing gas into the processing container;
a placing table including a lower electrode provided in the processing container;
an upper electrode provided above the placing table; and
a plurality of electromagnets including a plurality of coils provided coaxially around a central axis passing through a center of the placing table in a vertical direction, on the upper electrode,
the method further comprising:
generating plasma of the processing gas to perform a plasma etching on a single film of a workpiece placed on the placing table; and
repeatedly controlling a current supplied to each of the plurality of electromagnets to change a distribution of an etching rate of the single film in the diametric direction with respect to the central axis during the generating of the plasma of the processing gas.

2. The plasma etching method of claim 1 , wherein the controlling of the current supplied to each of the plurality of electromagnets comprises: a first step of setting the current supplied to the plurality of electromagnets to etch the single film with a distribution of a first etching rate as the distribution of the etching rate, and a second step of setting the current supplied to the plurality of electromagnets to etch the single film with a distribution of a second etching rate different from the first distribution of the first etching rate, as the distribution of the etching rate, and wherein the first step and the second step are alternately performed.

3. The plasma etching method of claim 1 , wherein the controlling of the current supplied to each of the plurality of electromagnets includes a plurality of steps of setting the current supplied to the plurality of electromagnets to sequentially etch the single film with a plurality of different etching rates in the diametric direction.

4. A plasma etching method, comprising:
generating plasma of the processing gas to perform a plasma etching on a single film of a workpiece placed on the placing table; and
controlling a current supplied to each of a plurality of electromagnet to change a distribution of an etching rate of the single film in a diametric direction with respect to a central axis during the generating of the plasma of the processing gas,
wherein the controlling of the current supplied to the plurality of electromagnet includes a plurality of steps of setting the current supplied to the plurality of electromagnets to sequentially etch the single film with a plurality of different etching rates in the diametric direction; and
wherein the plurality of steps of setting the current supplied to the plurality of electromagnets are repeated.

5. The plasma etching method of claim 4 , wherein the plurality of electromagnets each includes a coil extending about a circumferential direction around the central axis, and the coils of the electromagnets are at different radial distances from the central axis.

6. The plasma etching method of claim 1 , wherein the plurality of electromagnets each includes a coil extending about a circumferential direction around the central axis, and the coils of the electromagnets are at different radial distances from the central axis.

Assignees

• Tokyo Electron Ltd

Inventors

• Yokota Akihiro
• Himori Shinji
• Ohshita Tatsuro
• Kusano Shu
• Ito Etsuji
• Nagaseki Kazuya

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H01L21/67069

  Electricity · mapped topic

• H01J37/32091

  the radio frequency energy being capacitively coupled to the plasma · CPC title

• H01J37/32669 Primary

  Particular magnets or magnet arrangements for controlling the discharge · CPC title