News Column

Patent Issued for Substrate Holder Positioning Method and Substrate Processing System

July 2, 2014



By a News Reporter-Staff News Editor at Journal of Engineering -- According to news reporting originating from Alexandria, Virginia, by VerticalNews journalists, a patent by the inventors Douki, Yuichi (Koshi, JP); Hayashi, Tokutarou (Koshi, JP); Iida, Naruaki (Koshi, JP); Enokida, Suguru (Koshi, JP), filed on February 27, 2012, was published online on June 17, 2014.

The assignee for this patent, patent number 8755935, is Tokyo Electron Limited (Minato-Ku, JP).

Reporters obtained the following quote from the background information supplied by the inventors: "The present invention relates to a substrate holder positioning method, and a substrate processing system

"A substrate processing system is used for fabricating semiconductor devices including flat panel displays (FPDs). The substrate processing system has processing modules and a substrate carrying mechanism for carrying a substrate from and to the processing modules. The substrate carrying mechanism of the substrate processing system delivers substrates sequentially to the processing modules. The processing modules process the substrates by predetermined processes, respectively. It is possible that the entire surface of the substrate cannot be uniformly processed unless the substrate is positioned correctly at a predetermined position in each processing module. Although the substrate carrying mechanism is constructed so as to exhibit high carrying accuracy, a positioning operation is essential to accurately positioning the substrate.

"A substrate holder positioning method disclosed in, for example, Patent document 1 or 2 carries a positioning device provided with a detector, such as a camera or an image sensor, by the substrate holder, determines a distance of the substrate holder from a predetermined reference position on the basis of the position of the substrate holder determined by the detector, and then executes a correcting operation, namely, a teaching operation, for correcting the dislocation of the substrate holder from the reference position.

"Patent document 1: JP-A 2009-54665 Patent document 2: JP-A 2008-109027"

In addition to obtaining background information on this patent, VerticalNews editors also obtained the inventors' summary information for this patent: "When the positioning device is employed, it is possible that the positioning device causes a positioning error unless the positioning device is inspected and calibrated frequently. If the positioning device is not properly handled, correct positioning cannot be achieved in some cases. The positioning device is comparatively expensive and, in some cases, a plurality of positioning devices suitable to the respective shapes of the processing modules to which substrates are carried are needed. Those positioning devices increase the cost of the substrate holder considerably. Therefore, it is desired to position the substrate holder without using any positioning device.

"The present invention provides a substrate holder positioning device capable of positioning a substrate holder at a desired position without using any positioning device, and a substrate processing system.

"A substrate holder positioning method in a first mode of the present invention includes the steps of: measuring a first position of a substrate held by a substrate holder included in a substrate carrying mechanism; carrying the substrate held by the substrate holder to a substrate rotating unit for holding and rotating the substrate; turning the substrate held by the substrate rotating unit through a predetermined angle by the substrate rotating unit; transferring the substrate turned by the substrate rotating unit from the substrate rotating unit to the substrate holder; measuring a second position of the substrate transferred from the substrate rotating unit to the substrate holder; determining a position of a center of rotation of the substrate rotating unit on the basis of positions determined respectively of the first and the second position measuring; and positioning the substrate holder on the basis of the center of rotation.

"A substrate processing system including: a substrate carrying mechanism including a substrate holder for holding and carrying a substrate; position measuring devices combined with the substrate holder to measure the position of the substrate held by the substrate holder; a substrate rotating unit for holding and rotating the substrate, capable of receiving the substrate from and returning the substrate to the substrate holder; and a control unit for determining the position of the center of rotation of the substrate rotating unit on the basis of a first position of the substrate held by the substrate holder and a second position of the substrate held by the substrate holder after the substrate has been turned through a predetermined angle by the substrate rotating unit and has been received from the substrate rotating unit measured by the position measuring devices, and positioning the substrate holder on the basis of the position of the center of rotation of the substrate rotating unit.

"A substrate processing system in a third mode of the present invention includes: a substrate support unit onto which a substrate holder included in a substrate carrying mechanism delivers a substrate; and three or more substrate support members capable of coming into contact with the edge of the substrate held by the substrate holder to support the substrate and arranged such that the position of the substrate supported on the three or more substrate support members corresponds to a correct position of the substrate on the substrate support unit.

"A substrate holder positioning method of positioning a substrate holder included in a substrate carrying mechanism, to be executed by a substrate processing system including a substrate support unit onto which a substrate holder of the substrate carrying mechanism delivers a substrate, and three or more substrate support members capable of coming into contact with the edge of the substrate supported on the substrate support unit to support the substrate and arranged such that a position of the substrate supported on the three or more substrate support members coincides with a correct position of the substrate on the substrate support unit, including the steps of: carrying a substrate by the substrate holder and supporting the substrate on the three or more substrate support members; transferring the substrate supported on the three or more substrate support members from the three or more substrate support members to the substrate holder; measuring the position of the substrate held by the substrate holder; and positioning the substrate holder on the basis of the measured position of the substrate.

"A substrate holder positioning method of positioning a substrate holder included in a substrate carrying mechanism in a fifth mode of the present invention includes the steps of: holding a substrate by the substrate holder included in the substrate carrying mechanism; determining whether or not there is a substrate by a substrate detector mounted on the substrate holder by lowering the substrate holder holding a substrate from a position above a substrate support unit on which the substrate is to be placed toward the substrate support unit by a predetermined distance; repeating the step of determining whether or not there is a substrate when it is determined that there is a substrate; and deciding, when it is decided that there is no substrate in the step of determining whether or not there is a substrate, that the position of the substrate holder at a moment when it is decided that there is no substrate is a reference position of the substrate holder with respect to a vertical direction.

"A substrate holder positioning method in a sixth mode of the present invention includes the steps of: supporting a substrate by a central part of the back surface of the substrate by a back support unit; advancing a substrate holder included in a substrate carrying mechanism to a position under the substrate supported by the back support unit; determining whether or not there is a substrate by a substrate detecting unit mounted on the substrate holder by raising the substrate holder by a predetermined distance toward the substrate and; repeating the step of determining whether or not there is a substrate when it is decided that there is no substrate in the step of detecting whether or not there is a substrate; and deciding that the position of the holding unit at a moment when it is decided that there is a substrate in the step of determining whether or not there is a substrate is a reference position with respect to a vertical direction.

"The substrate holder positioning method and the substrate processing system can position the substrate holder without using any positioning device."

For more information, see this patent: Douki, Yuichi; Hayashi, Tokutarou; Iida, Naruaki; Enokida, Suguru. Substrate Holder Positioning Method and Substrate Processing System. U.S. Patent Number 8755935, filed February 27, 2012, and published online on June 17, 2014. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=8755935.PN.&OS=PN/8755935RS=PN/8755935

Keywords for this news article include: Tokyo Electron Limited.

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC


For more stories covering the world of technology, please see HispanicBusiness' Tech Channel



Source: Journal of Engineering