US 12,247,927 B2
Method of evaluating semiconductor wafer
Motoi Kurokami, Osaka (JP); and Keiichiro Mori, Saga (JP)
Assigned to SUMCO CORPORATION, Tokyo (JP)
Appl. No. 17/926,514
Filed by SUMCO CORPORATION, Tokyo (JP)
PCT Filed Mar. 3, 2021, PCT No. PCT/JP2021/008135
§ 371(c)(1), (2) Date Nov. 18, 2022,
PCT Pub. No. WO2021/250949, PCT Pub. Date Dec. 16, 2021.
Claims priority of application No. 2020-099230 (JP), filed on Jun. 8, 2020.
Prior Publication US 2023/0194438 A1, Jun. 22, 2023
Int. Cl. G01N 21/95 (2006.01); G01N 21/88 (2006.01); G01N 21/956 (2006.01)
CPC G01N 21/9501 (2013.01) [G01N 21/8806 (2013.01); G01N 21/95607 (2013.01); G01N 2021/8848 (2013.01); G01N 2021/95615 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A method of evaluating a semiconductor wafer by a laser surface inspection device,
wherein the semiconductor wafer comprises a coating layer on a semiconductor substrate,
the laser surface inspection device comprises:
a first incident system,
a second incident system making a light incident upon a surface to be irradiated at an incidence angle higher than an incidence angle of a light to be made incident upon the surface to be irradiated by the first incident system,
a first light receiving system,
a second light receiving system, and
a third light receiving system,
the three kinds of light receiving systems are different in one or more selected from the group consisting of a light-receiving angle at which a light radiated from the surface to be irradiated is received and polarization selectivity, respectively,
the method comprises:
performing evaluation of the semiconductor wafer by detecting a defect kind selected from the group consisting of a deposit and a non-deposited convex defect present on a surface of the coating layer as a light point defect based on a plurality of measurement results including three kinds of low incidence angle measurement results obtained by, on the surface of the coating layer, reception of a radiated light radiated by reflection or scattering of a light incident from the first incident system at the surface by the three kinds of light receiving systems, and at least one high incidence angle measurement result obtained by reception of a radiated light radiated by reflection or scattering of a light incident from the second incident system at the surface by at least one of the three kinds of light receiving systems, and
distinguishing whether the defect kind detected as the light point defect is a deposit or a non-deposited convex defect based on a distinguishing criterion selected from the group consisting of,
presence or absence of detection and a detection size in measurement result 1 obtained by the combination of the first incident system and the first light receiving system,
presence or absence of detection and a detection size in measurement result 2 obtained by the combination of the first incident system and the second light receiving system,
presence or absence of detection and a detection size in measurement result 3 obtained by the combination of the first incident system and the third light receiving system, and
presence or absence of detection and a detection size in measurement result 4 obtained by the combination of the second incident system and the second light receiving system or the third light receiving system,
wherein
the first light receiving system receives an omnidirectional light,
the second light receiving system selectively receives a polarized light at an azimuth angle θ1°,
the third light receiving system selectively receives a polarized light at an azimuth angle θ2° different from the azimuth angle θ1°, where 0°≤θ1°≤90° and 90°≤θ2°≤180°,
a light-receiving angle of the first light receiving system is a higher angle than a light-receiving angle of the second light receiving system and a light-receiving angle of the third light receiving system, and
wherein the distinguishing is performed according to the distinguishing criteria shown in Table 1 below, in Table 1, X, Y, and Z are each independently more than 0;
TABLE 1
 
 
 Defect
Distinguishing criteria kind
 
(1) Exceeding the detection upper limit size in at least one of Deposit
measurement result 1, measurement result 2, and measurement result 3.
 
(2) Other than the light point defect distinguished in terms of defect Deposit
kind in the (1), detected in the measurement result 2, and not detected
 
in the measurement result 3.
 
(3) Other than the light point defect distinguished in terms of defect Non-deposited
kind in the (1) or the (2), detected in the measurement result 3, and not convex
detected in the measurement result 2. defect
(4) Other than the light point defect distinguished in terms of defect Deposit
kind in any of the (1) to (3), detected in the measurement result 2, and
 
not detected in the measurement result 1
 
(5) Other than the light point defect distinguished in terms of defect Non-deposited
kind in any of the (1) to (4), the detection size in the measurement convex defect
result 4 and the detection size in the measurement result 2 being both
 
more than 0, and the detection size ratio satisfying any of
 
(detection size in measurement result 2)/(detection size in
 
measurement result 4) > X, and
 
(detection size in measurement result 2)/(measured size in
 
measurement result 4) < Y.
 
(6) Other than the light point defect distinguished in terms of defect Deposit
kind in any of the (1) to (4), the detection size in the measurement
 
result 4 and the detection size in the measurement result 2 both being
 
more than 0, and the detection size ratio satisfying
 
Y < (detection size in measurement result 2)/(detection size in
 
measurement result 4) < X.
 
(7) Other than the light point defect distinguished in terms of defect Non-deposited
kind in any of the (1) to (6), the detection size in the measurement convex defect
result 2 and the detection size in the measurement result 3 both being
 
more than 0, and the size ratio of detection size in measurement result
 
2 and detection size in measurement result 3 satisfying
 
(detection size in measurement result 2)/(detection size in
 
measurement result 3) > Z.
 
(8) Other than the light point defects distinguished in terms of defect Deposit
kind in the (1) to (7).