Semiconductor wafer surface treatment method

Claim 2

A semiconductor wafer surface treatment method for forming gettering damages on the surface of the semiconductor wafer, characterized in that an ultrasonic wave is propagated to the surface of said semiconductor wafer (15) via a treatment solution (11) to form mecha­nical damages only on one surface of said semiconductor wafer (15), while, at the same time, cleaning the surface of said semiconductor wafer (15).

Claim 3

A semiconductor wafer surface treatment method according to claim 1, characterized in that the output power of the ultrasonic waves is selected to be within the range of 50 W to 500 W, and the frequency of the ultrasonic waves is selected to be within the range of 10 KHz to 100 KHz.

Claim 4

A semiconductor wafer surface treatment method according to claim 1, characterized in that said treatment solution is selected from a group consisting of ultra-pure water (11) and pure water.

Claim 5

A semiconductor wafer surface treatment method according to claim 1, characterized in that said one of the surfaces of said wafer is a back-side surface opposite to a main surface in which semiconductor ele­ments are to be formed in the later steps.

Claim 6

A semiconductor wafer surface treatment method according to claim 1, characterized in that said mecha­nical damage formation and cleaning step is effected by placing said semiconductor wafer (15) with one surface thereof set in contact with pure water filling a treatment bath (10) and propagating ultrasonic wave generated from ultrasonic wave generating means (12 and 13) disposed on the bottom of said treatment bath (10) into the pure water.

Claim 7

A semiconductor wafer surface treatment method for forming gettering damages on the surface of said semiconductor wafer, characterized in that an ultrasonic wave is propagated to the surface of said semiconductor wafer (25, 36) via a treatment solution (27, 29) to form mechanical damages on only one surface of said semicon­ductor wafer (25, 36) and at the same time clean both surfaces of said semiconductor wafer (25, 36).

Claim 8

A semiconductor wafer surface treatment method for forming gettering damages on the surface of said semiconductor wafer, characterized in that an ultrasonic wave is propagated to the surface of said semiconductor wafer (25, 36) via a treatment solution (27, 29) to form mechanical damages on only one surface of said semicon­ductor wafer (25, 36) and at the same time clean both surfaces of said semiconductor wafer (25, 36).

Claim 9

A semiconductor wafer surface treatment method according to claim 6, characterized in that the output power of the ultrasonic waves is selected to be within the range of 50 W to 500 W, and the frequency of the ultrasonic waves is selected to be within the range of 20 KHz to 100 KHz.

Claim 10

A semiconductor wafer surface treatment method according to claim 6, characterized in that said treatment solution is selected from a group consisting of ultra-pure water (27, 29) and pure water.

Claim 11

A semiconductor wafer surface treatment method according to claim 6, characterized in that said one of the surfaces of said semiconductor wafer is a back-side surface opposite to a main surface in which semiconduc­tor elements are to be formed in the later steps.

Claim 12

A semiconductor wafer surface treatment method according to claim 6, characterized in that said mecha­nical damage formation and cleaning step is effected by submerging semiconductor wafers (25) in to a treatment bath (20) filled with pure water, generating ultrasonic waves from ultrasonic wave generating means (12 and 13) disposed to face the surface of said semiconductor wafers (25) in said treatment bath (20), and propagating the ultrasonic waves into the pure water.

Claim 13

A semiconductor wafer surface treatment method according to claim 10, characterized in that said ultrasonic wave generating means (22 and 23) is disposed on the bottom portion of said treatment bath (20), and a main surface of each of said semiconductor wafers (25) opposite to said one surface in which said mechanical damages are formed, is cleaned by ultrasonic wave reflected from the surface of the pure water.

Claim 14

A semiconductor wafer surface treatment method according to claim 10, characterized in that said ultrasonic wave generating means (22 and 23) is disposed on a first side wall portion of said treatment bath (20), and a main surface of each of said semiconductor wafers (25) opposite to said one surface in which said mechanical damages are formed, is cleaned by ultrasonic waves reflected from a second side wall portion of said treatment bath (20) which is opposite to the first side wall portion.

Claim 15

A semiconductor wafer surface treatment method according to claim 6, characterized in that said mecha­nical damage formation and cleaning step is effected by placing said semiconductor wafer (36) with one surface thereof set in contact with pure water filling a treat­ment bath (30), propagating ultrasonic waves generated from ultrasonic wave generating means (33 and 34) disposed on the bottom of said treatment bath (30) into the pure water to form mechanical damages on one surface of said semiconductor wafer (36) and, at the same time to clean said one surface of said semiconductor wafer (36), and spraying cleaning solution onto the other surface of said semiconductor wafer (36) from a nozzle (38, 41) disposed above said other surface of said semiconductor wafer (36) to clean said other surface of said semiconductor wafer (36).

Claim 16

A semiconductor wafer surface treatment method according to claim 13, characterized in that the treat­ment is effected under a condition such that said semiconductor wafer (36) is rotated.

Claim 17

A semiconductor wafer surface treatment method according to claim 13, characterized in that said nozzle (38, 41) is moved to clean said other surface of said semiconductor wafer (36).