公开(公告)号：AU2002341544A1

公开(公告)日：2003-01-29

申请号：AU2002341544

申请日：2002-07-12

Applicant: RUDOLPH TECHNOLOGIES INC

Inventor： STONER ROBERT J ,  MORATH CHRISTOPHER

IPC: G01B11/06 ,  G01B11/28 ,  G01B9/02

Abstract: An apparatus for improving the signal to noise ratio of measurements of the thickness of layers in a thin film stack uses a photoacoustic measurement system that includes a time differentiation system for inducing a delay in pump beam pulses. The time differentiation system uses, among other things, a birefringent element and other elements to control the polarization of pump beam pulses. Use of the apparatus involves applying a time varying voltage to an electro-optic modulator driver and setting a time differentiation step; or, in another embodiment, applying a time varying voltage to an electro-optic modulator to induce a fixed time delay delta-t between a vertically polarized pulse and a horizontally polarized pulse. The high frequency operation of the system provides for improved determinations of film thickness.

公开(公告)号：WO03006918A3

公开(公告)日：2003-10-02

申请号：PCT/US0222222

申请日：2002-07-12

Applicant: RUDOLPH TECHNOLOGIES INC

Inventor： MORATH CHRISTOPHER ,  STONER ROBERT J

IPC: G01B11/06 ,  G01B11/28 ,  G01B9/02

CPC classification number: G01B11/0666 ,  G01B11/28 ,  G01N21/1702 ,  G01N2021/1706

Abstract: An apparatus for improving the signal to noise ratio of measurement of the thickness of layers in a thin film stack uses a photoa coustic measurement system (75) that includes a time differentiation system (130) for inducing a delay in pump beam pulses (125A). The time differentiation system (130) uses, among other things, a birefringent element and other elements to control the polarization of pump beam pulses (125A). Use of the apparatus involves applying a time varying voltage to an electro-optic modulator driver and setting a time differentiation step; or, in another embodiment, applying a time varying voltage to an electro-optic modulator to induce a fixed time delay delta-t between a vertically polarized pulse and a horizontally polarized pulse. The high frequency operation of the system provides for improved determinations of film thickness.

Abstract translation: 一种用于提高薄膜堆叠中的层厚测量的信噪比的装置使用包括用于引起泵浦光束脉冲（125A）中的延迟的时间微分系统（130）的照相沉积测量系统（75） 。 时间微分系统（130）尤其使用双折射元件和其​​它元件来控制泵浦光束脉冲（125A）的极化。 使用该装置包括对电光调制器驱动器施加时变电压并设定时间分化步骤; 或者在另一个实施例中，向电光调制器施加时变电压以引起垂直极化脉冲和水平极化脉冲之间的固定时间延迟Δ-t。 该系统的高频操作提供了改进的膜厚度测定。

公开(公告)号：EP1417450A4

公开(公告)日：2009-06-10

申请号：EP02775693

申请日：2002-07-12

Applicant: RUDOLPH TECHNOLOGIES INC

Inventor： MORATH CHRISTOPHER ,  STONER ROBERT J

IPC: G01B11/06 ,  G01B11/28

CPC classification number: G01B11/0666 ,  G01B11/28 ,  G01N21/1702 ,  G01N2021/1706

Abstract: An apparatus for improving the signal to noise ratio of measurements of the thickness of layers in a thin film stack uses a photoacoustic measurement system that includes a time differentiation system for inducing a delay in pump beam pulses. The time differentiation system uses, among other things, a birefringent element and other elements to control the polarization of pump beam pulses. Use of the apparatus involves applying a time varying voltage to an electro-optic modulator driver and setting a time differentiation step; or, in another embodiment, applying a time varying voltage to an electro-optic modulator to induce a fixed time delay delta-t between a vertically polarized pulse and a horizontally polarized pulse. The high frequency operation of the system provides for improved determinations of film thickness.

公开(公告)号：EP1381825A4

公开(公告)日：2009-05-06

申请号：EP02721330

申请日：2002-03-08

Applicant: RUDOLPH TECHNOLOGIES INC

Inventor： MORATH CHRISTOPHER ,  VERTIKOV ANDREY

IPC: G01B11/06

CPC classification number: G01N29/2418 ,  G01B11/0666

Abstract: Disclosed are methods and apparatus for reducing thermal loading of a film (220) disposed while measuring the thickness of the film in an area about a measurement site. The method includes steps of bringing an optical assembly of the measurement system (75) into focus, aligning a beam spot with the measurement site, turning on one of a dither EOM (205) of a dither AOM of a piezo-electric dither assembly to sweep the beam spot in an area about the measurement site, thereby reducing the thermal loading within the measurement site, making a measurement data to determine an average film thickness in the measurement area.