Tokyo Electron Limited

Other

Kouichiro Inazawa

Masahiro Yamada

Youbun Ito

Eiichi Nishimura

Vaidyanathan Balasubramaniam

Masaaki Hagiwara

Shin Okamoto

Kunihiko Hinata

Tomoki Suemasa

Abron S Toure

Tsuyoshi Ono

Hiromi Sakima

Makoto Sekine

Yukimasa Yoshida

Itsuko Sakai

Koichi Yatsuda

Kimihiro Higuchi

Takashi Akahori

Yoshiki Igarashi

Masaaki Hagihara

Yasunori Hatamura

Ralph Kim

Kouji Senoo

Tetsuya Nishiara

Maki Koizumi

Sachiko Furuya

Philip Sansone

A method for etching an organic anti-reflective coating (ARC) layer on a substrate in a plasma processing system comprising: introducing a process gas comprising nitrogen (N), hydrogen (H), and oxygen (O); forming a plasma from the process gas; and exposing the substrate to the plasma. The process gas can, for example, constitute an NH/O, N/H/O, N/H/CO, NH/CO, or NH/CO/Obased chemistry. Additionally, the process chemistry can further comprise the addition of helium. The present invention further presents a method for forming a bilayer mask for etching a thin film on a substrate, wherein the method comprises: forming the thin film on the substrate; forming an ARC layer on the thin film; forming a photoresist pattern on the ARC layer; and transferring the photoresist pattern to the ARC layer with an etch process using a process gas comprising nitrogen (N), hydrogen (H), and oxygen (O).

Method and apparatus for bilayer photoresist dry development

A method is provided for plasma ashing to remove photoresist remnants and etch residues that are formed during preceding plasma etching of dielectric layers. The ashing method uses a two-step plasma process involving an oxygen-containing gas, where low or zero bias is applied to the substrate in the first cleaning step to remove significant amount of photoresist remnants and etch residues from the substrate, in addition to etching and removing detrimental fluoro-carbon residues from the chamber surfaces. An increased bias is applied to the substrate in the second cleaning step to remove the remains of the photoresist and etch residues from the substrate. The two-step process reduces the memory effect commonly observed in conventional one-step ashing processes. A method of endpoint detection can be used to monitor the ashing process.

Method for removing photoresist and etch residues

A method is provided for plasma ashing to remove photoresist remnants and etch residues that are formed during preceding plasma etching of dielectric layers. The ashing method uses a two-step plasma process involving an hydrogen-containing gas, where low or zero bias is applied to the substrate in the first cleaning step to remove significant amount of photoresist remnants and etch residues from the substrate, in addition to etching and removing detrimental fluoro-carbon residues from the chamber surfaces. An increased bias is applied to the substrate in the second cleaning step to remove the remains of the photoresist and etch residues from the substrate. The two-step process reduces the memory effect commonly observed in conventional one-step ashing processes. A method of endpoint detection can be used to monitor the ashing process.

A lower electrode with the temperature at its mounting surface set at 40&deg; C. is provided inside a processing chamber of an etching apparatus . After a wafer W is placed on the lower electrode , a processing gas with its gas composition and gas flow rate expressed as C F : CH F : Ar&equals;7:4:500 (sccm) is induced into the processing chamber while sustaining the pressure of the atmosphere inside the processing chamber at 50 (mTorr). High-frequency power at 1500 (W) with the frequency at 13.56 (MHz) is applied to the lower electrode to generate plasma. With the plasma thus generated, a carbon film is formed at shoulder of an SiN film layer exposed inside a contact hole and, at the same time, accumulation of carbon at the bottom of the contact hole is prevented, to form a contact hole achieving a high aspect ratio while preventing damage to the SiN film layer.

Etching method

Method of manufacturing semiconductor device

In a processing chamber of an etching apparatus a lower electrode and an upper electrode grounded through a processing container are disposed oppositely to each other. A first high frequency power supply section composed of a first filter, a first matching device, and a first power source, and a second high frequency power supply section composed of a second filter, a second matching device, and a second power source are connected to the lower electrode. A superimposed power of two frequencies composed of a first high frequency power component of at least 10 MHz produced from the first power source and a second high frequency power component of at least 2 MHz produced from the second power source is applied to the lower electrode. Ions in the plasma do not accelerated by changes of electric field in the processing chamber, but are accelerated by a self-bias voltage and collide only against a wafer on the lower electrode.

Plasma processing method

A processing gas constituted of C F , O and Ar achieving a flow rate ratio of 1&lE;C F flow rate/O flow rate&lE;1.625 is supplied into a processing chamber of an etching apparatus and the atmosphere pressure is set within a range of 45 mTorr&tilde;50 mTorr. High-frequency power is applied to a lower electrode sustained within a temperature range of 20&deg; C.&tilde;40&deg; C. on which a wafer W is mounted to raise the processing gas to plasma, and using the plasma, a contact hole is formed at an SiO film on an SiNx film formed at the wafer W. The use of C F and O makes it possible to form a contact hole achieving near-perfect verticality at the SiO film and also improves the selection ratio of the SiO2 film relative to the SiNx film . C F , which becomes decomposed over a short period of time when released into the atmosphere, does not induce the greenhouse effect.

An etching gas is supplied into a process chamber and turned into plasma so as to etch a silicon nitride film arranged on a field silicon oxide film on a wafer (w). A mixture gas containing at least CH F gas and O gas is used as the etching gas. Parameters for planar uniformity, by which the etching apparatus is set in light of a set value of the planar uniformity, include the process pressure and the mixture ratio (CH F /O ) of the mixture gas. As the set value of the planar uniformity is more strict, either one of the process pressure and the mixture ratio is set higher.

Plasma etching method

A method and system for processing a substrate in the presence of high purity C F . When processing oxides and dielectrics in a gas plasma processing system, C F is used in combination with a carrier gas (e.g., Ar) and one or more of CO and O . When using a silicon nitride (Si N ) layer as an etch stop, effective etching is performed due to the selectivity of oxides versus silicon nitride. The method is used when etching down to self-aligning contacts and other layers. The method may be practiced with or without using an anti-reflective coating underneath the photoresist layer.

Etchant for use in a semiconductor processing method and system

A method and system for processing a substrate in the presence of high purity C.sub.5 F.sub.8. When processing oxides and dielectrics in a gas plasma processing system, C.sub.5 F.sub.8 is used in combination with a carrier gas (e.g., Ar) and one or more of CO and O.sub.2. When using a silicon nitride (Si.sub.x N.sub.y) layer as an etch stop, effective etching is performed due to the selectivity of oxides versus silicon nitride. The method is used when etching down to self-aligning contacts and other layers. The method may be practiced with or without using an anti-reflective coating underneath the photoresist layer.

Semiconductor processing method and system using C.sub.5 F.sub.8

In a plasma etching apparatus, a process gas is supplied into a process chamber and converted into plasma by means of RF discharge, and a semiconductor wafer placed on a lower electrode is etched by the plasma. An RF power supply mechanism is connected to the lower electrode for applying thereto a superposed RF power for forming an RF electric field in the process chamber. The RF power supply mechanism has first and second RF power supplies for respectively oscillating a low frequency RF component and a high frequency RF component having a higher frequency than the low frequency RF component. The high frequency RF component from the second frequency RF component supply has its wave form modulated by a modulator on the basis of the wave form of the low frequency RF component from the first frequency RF power supply. Thereafter, the modulated high frequency RF component and the low frequency RF component are superposed upon each other. The high frequency RF component has a larger amplitude at a negative side peak of the low frequency RF component than at a positive side peak of the low frequency RF component.

Plasma processing apparatus

An etching method comprising the steps of forming an etched layer on a wafer and covering the etched layer with an anti-reflection cover and then the anti-reflection cover with a photoresist film, pattern-exposing the photoresist film, developing the exposed photoresist film to form pattern openings in each of which the anti-reflection cover is exposed, and carrying the wafer into a chamber, exhausting the chamber to decompressed atmosphere, and introducing a mixed gas of C.sub.4 F.sub.8 gas and at least one of O.sub.2 and N.sub.2 gases into the process chamber to generate plasma of this mixed gas and act active species in this plasma on the wafer, whereby the anti-reflection cover which is exposed in each of the pattern openings is etched and the etched layer is then etched without etching the photoresist film formed on an inner surface each pattern opening.

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Tokyo, Japan

Kouichiro Inazawa