US 7,126,697 B2Granted

Method and apparatus for determining endpoint of semiconductor element fabricating process

AssigneeHitachi, Ltd.

InventorsTatehito Usui, Takashi Fujii, Motohiko Yoshigai, Tetsunori Kaji, Hideyuki Yamamoto

Life of this patent

Estimating the term…

Loading patent…

Abstract

Standard patterns of differential values of interference light that correspond to a predetermined step height of the first material being processed and standard patterns of differential values of interference light that correspond to a predetermined remaining mask layer thickness of the material are set. These standard patterns use wavelengths as parameters. Then, the intensities of interference light of multiple wavelengths are measured for a second material that has the same structure as the first material. Actual patterns with wavelength as parameter are determined from differential values of the measured interference light intensities. Based on the standard patterns and the actual patterns of the differential values, the step height and the remaining mask layer thickness of the second material are determined.

Claims8

Dependent claims

A method of processing a semiconductor wafer comprising:

a step of setting a standard pattern consisting of a time differential value of an interference light for each of multiple wavelengths from a first film to be processed overlying a second film that corresponds to a predetermined film process quantity of the first film;
a step of etching a same structure on the semiconductor wafer as the first film overlying the second film, measuring an intensity of an interference light for each of the multiple wavelengths from the first film and determining an actual pattern consisting of a time differential value of the measured interference light intensity for each of the multiple wavelengths;
a step of determining a remaining thickness of the first film based on the standard pattern consisting of time differential values and the actual pattern consisting of time differential values;
and
a step of etching the first film remaining after a determination of the thickness of the first film reaching a predetermined value with a changed etching condition during a predetermined time period.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/340,559Filed 27 Jan 2006 · continuation
Priority: 6 Sep 2001
Published: US 2006/0132798 A122 Jun 2006
Granted: 24 Oct 2006
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

H01J 37/32963
Monitoring and controlling tubes by information coming from the object and/or discharge: end-point detection
G01B 11/0675
Of coating: using interferometry
H10P 74/238
Characterised by multiple measurements, corrections, marking or sorting processes: comprising acting in response to an ongoing measurement without…
H01J
Electric discharge tubes or discharge lamps

Family

Application09/946,504Parent of this continuation · filed 6 Sep 2001
Application10/978,412Parent of this continuation · filed 2 Nov 2004
US 2006/0132798 A1Pre-grant publication · published 22 Jun 2006
US 7,009,715 B2Parent of this continuation
US 6,903,826 B2Parent of this continuation
US 2003/0043383 A1Published application
US 2005/0062982 A1Published application
US 7,126,697 B2This patent

From the US filing history. Foreign family members aren’t listed.