Habib N Najm

US Patent:

55089348, Apr 16, 1996

Filed:

May 4, 1994

Appl. No.:

8/237971

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib N. Najm - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01S 506

US Classification:

364468

Abstract:

A computer controlled system for real-time control of semiconductor wafer fabrication process uses a multi-point, real-time, non-invasive, in-situ pyrometry-based temperature sensor with emissivity compensation to produce semiconductor wafer reflectance, transmittance, and radiant heat energy measurements. The temperature values that the sensor determines are true temperatures for various points on the wafer. The process control computer stores surface roughness values for the semiconductor wafer being examined. The surface roughness values are produced by surface roughness sensor that makes non-invasive and in-situ measurements. The surface roughness sensor performs roughness measurements of the semiconductor wafer based on coherent reflectance and scatter reflectance of the wafer. Based on surface roughness measurements, the process control computer can use the real-time, in-situ measurements of the multi-point pyrometry-based sensor to obtain real-time measurements of time wafer temperature distribution. By associating a multi-zone lamp module having a real-time controller with the present invention a feedback circuit is provided for real-time precision semiconductor wafer process control.

US Patent:

53054172, Apr 19, 1994

Filed:

Mar 26, 1993

Appl. No.:

8/037771

Inventors:

Habib N. Najm - Dallas TX
Mehrdad M. Moslehi - Dallas TX
Somnath Banerjee - Dallas TX
Lino A. Velo - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01J 506

US Classification:

392418

Abstract:

In a RTP reactor where wafer temperature is measured by a pyrometer assembly (32), a pyrometer assembly (50) is further provided to measure the temperature of the quartz window (30) that is situated between the wafer pyrometer assembly (32) and the wafer (16) that is being processed. During the calibration procedure (100, 120) where a thermocouple wafer is used, the measurements from the wafer pyrometer assembly (32) and the window pyrometer assembly (50) are calibrated, and pyrometer measurements and thermocouple measurements are collected and compiled into calibration tables. During actual RTP reactor operation, the data from the calibration tables and current wafer and window pyrometer measurements are used to compute corrected wafer temperature(s). The corrected wafer temperature(s) is/are then used to control the intensities of the heating lamps according to the wafer processing heating schedule.

US Patent:

51564610, Oct 20, 1992

Filed:

May 17, 1991

Appl. No.:

7/702646

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib N. Najm - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01J 510

US Classification:

374121

Abstract:

A multi-point non-invasive, real-time pyrometry-based temperature sensor (200) for simultaneously sensing semiconductor wafer (22) temperature and compensating for wafer emissivity effects. The pyrometer (200) measures the radiant energy that a heated semiconductor wafer (22) emits and coherent beams of light (224) that the semiconductor wafer (22) reflects. As a result, the sensor (200) generates accurate, high-resolution multi-point measurements of semiconductor wafer (22) temperature during a device fabrication process. The pyrometer (200) includes an infrared laser source (202) that directs coherent light beam (203) into beam splitter (204). From the beam splitter (204), the coherent light beam (203) is split into numerous incident coherent beams (210). Beams (210) travel via optical fiber bundles (218) to the surface of semiconductor wafer (22) within the fabrication reactor (80). Each optical fiber bundle (218) collects reflected coherent light beam and radiant energy from wafer (22).

US Patent:

53176561, May 31, 1994

Filed:

Feb 11, 1993

Appl. No.:

8/017359

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib N. Najm - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G02B 602

US Classification:

385 12

Abstract:

A fiber-optic network for communicating non-invasive, real-time, in-situ semiconductor wafer radiance and emissivity measurements. The fiber-optic network includes a plurality of optical fibers, a plurality of fiber-optic bundles, and a chopper multiplexer. The fiber-optic bundle provides for the simultaneous transmission and receipt of coherent infrared light energy and radiant heat energy from a semiconductor wafer within a fabrication reactor. The fiber-optic bundles are designed to be sufficiently small to fit within hollow light pipe in a lamp module that directs optical heating energy to the wafer. This substantially eliminates measurement error that the lamp module generates in known measurement devices. Use of optical fibers for transmitting and receiving laser energy and wafer radiance permits precision placement of the fiber-optic bundles to measure multiple temperatures on the semiconductor wafer surface.

US Patent:

54353793, Jul 25, 1995

Filed:

Aug 14, 1992

Appl. No.:

7/930074

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib N. Najm - Dallas TX
Ajit P. Paranjpe - Dallas TX
Cecil J. Davis - Greenville TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

F28D 1500

US Classification:

165 804

Abstract:

A chilling system (12) has a container (20) filled with a coolant (22). A pipe (16) traverses within the container (20) and the coolant (22) to a housing (18). Fluid flows within the pipe (16) and becomes chilled through the pipe (16) upon entering the container (20) and the coolant (22). The chilled fluid enters the housing (18) chilling the housing (18) through the pipe (16). In turn, semiconductor substrate (19) in contact with the housing (18) also is chilled.

US Patent:

52552861, Oct 19, 1993

Filed:

Jul 10, 1992

Appl. No.:

7/911609

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib N. Najm - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01J 510

US Classification:

374121

Abstract:

A multi-point non-invasive, real-time pyrometry-based temperature sensor (200) for simultaneously sensing semiconductor wafer (22) temperature and compensating for wafer emissivity effects. The pyrometer (200) measures the radiant energy that a heated semiconductor wafer (22) emits and coherent beams of light (224) that the semiconductor wafer (22) reflects. As a result, the sensor (200) generates accurate, high-resolution multi-point measurements of semiconductor wafer (22) temperature during a device fabrication process. The pyrometer (200) includes an infrared laser source (202) that directs coherent light beam (203) into beam splitter (204). From the beam splitter (204), the coherent light beam (203) is split into numerous incident coherent beams (210). Beams (210) travel via optical fiber bundles (218) to the surface of semiconductor wafer (22) within the fabrication reactor (80). Each optical fiber bundle (218) collects reflected coherent light beam and radiant energy from wafer (22).

US Patent:

53455347, Sep 6, 1994

Filed:

Mar 29, 1993

Appl. No.:

8/039720

Inventors:

Habib N. Najm - Dallas TX
Steve S. Huang - Richardson TX
Cecil J. Davis - Greenville TX
Robert T. Matthews - Plano TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H01L 2120

US Classification:

392422

Abstract:

A thin reflective cylindrical baffle [20] in a radiant lamp heater is provided in the space below a plurality of heating bulbs [2,4,6] (arranged in a center position and around a middle and outer ring) and above a quartz window [12]. The baffle diameter is such that it fits within the annular space between the middle [4] and outer [6]ring of bulbs. The baffle which blocks a predetermined amount of light generated by the lamp bulbs [20] allows improved controllability of wafer temperature profile--for a wafer heated by a radiant lamp heater.

US Patent:

53261704, Jul 5, 1994

Filed:

Sep 1, 1993

Appl. No.:

8/115920

Inventors:

Mehrdad M. Moslehi - Dallas TX
Habib Najm - Dallas TX
Lino A. Velo - Dallas TX

Assignee:

Texas Instruments, Incorporated - Dallas TX

International Classification:

G01K 1500
G01J 554

US Classification:

374 2

Abstract:

A method for calibrating at least one temperature sensor. A wafer (30) having calibration structures of a material having a melting point in the range of 150. degree. to 1150. degree. C. is provided. The temperature sensor is operable to detect a temperature dependent characteristic of the wafer and output a signal corresponding to the temperature depending characteristic. The power input is selectively varied and the wafer temperature is ramped for a calibration run. A wafer characteristic, such as wafer reflectance, radiance, or emissivity, is monitored. A first step change in the wafer characteristic corresponding to a wafer temperature equal to the melting point of the calibration structures is detected and a set of calibration parameters for each temperature sensor being calibrated is calculated.