	US 7,349,088 B2
	Process monitoring system, process monitoring method, and method for manufacturing semiconductor device
Takayuki Sakai, Tokyo (Japan); Masanobu Kibe, Kanagawa (Japan); and Tokuhisa Ohiwa, Kanagawa (Japan)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan)
Filed on Jul. 31, 2007, as Appl. No. 11/882,275.
Application 11/882275 is a continuation of application No. 10/969860, filed on Oct. 22, 2004.
Claims priority of application No. P2003-362134 (JP), filed on Oct. 22, 2003.
Prior Publication US 2007/0273880 A1, Nov. 29, 2007
Int. Cl. G01J 4/00 (2006.01)

U.S. Cl. 356—364 [356/369]

4 Claims

1. A process monitoring method comprising:

inserting an object to be processed into a process chamber, the process chamber having a monitor window containing a birefringent material;

irradiating a light to the object through the monitor window;

polarizing the light;

adjusting a relationship between a polarization plane of the light and a direction of an optic axis of the monitor window;

detecting the light reflected from the object; and

obtaining information about a thickness direction of the object, based on the detected light.