Method of surface treatment for manufacturing semiconductor device

• US 7,179,746 B2
• Filed: 12/02/2003
• Issued: 02/20/2007
• Est. Priority Date: 12/02/2002
• Status: Expired due to Fees

• Current Assignee: Foundation for Advancement of International Science
• Original Assignee: Foundation for Advancement of International Science
• Inventors: Ohmi, Tadahiro, Sugawa, Shigetoshi, Teramoto, Akinobu, Akahori, Hiroshi, Nii, Keiichi
• Primary Examiner(s): PERT, EVAN T
• Application Number:
  US10/725,063
• Publication Number:
  US 20040108575A1
• Time in Patent Office: 1,176 Days
• Field of Search: 438/143, 438/719, 438/714, 438/197, 438/198, 438/697, 438/770, 257/627, 257/628
• US Class Current: 438/697
• CPC Class Codes: H01L 21/0214 the material being a silicon oxynitride, e.g. SiON or SiON:H
• CPC Class Codes: H01L 21/02142 the material containing silicon and at least one metal element, e.g. metal silicate based insulators or metal silicon oxynitrides
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02175 characterised by the metal H01L21/02197 takes precedence
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02301 in-situ cleaning
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: H01L 21/31654 of semiconductor materials, e.g. the body itself
• CPC Class Codes: H01L 21/318 composed of nitrides
• CPC Class Codes: H01L 21/3185 of siliconnitrides
• CPC Class Codes: H01L 29/6659 with both lightly doped source and drain extensions and source and drain self-aligned to the sides of the gate, e.g. lightly doped drain [LDD] MOSFET, double diffused drain [DDD] MOSFET

Abstract

In a semiconductor device formed on a silicon surface which has a substantial (110) crystal plane orientation, the silicon surface is flattened so that an arithmetical mean deviation of surface Ra is not greater than 0.15 nm, preferably, 0.09 nm, which enables to manufacture an n-MOS transistor of a high mobility. Such a flattened silicon surface is obtained by repeating a deposition process of a self-sacrifice oxide film in an oxygen radical atmosphere and a removing process of the self-sacrifice oxide film, by cleaning the silicon surface in deaerated H₂O or a low OH density atmosphere, or by strongly terminating the silicon surface by hydrogen or heavy hydrogen. The deposition process of the self-sacrifice oxide film may be carried out by isotropic oxidation.

Claims

1. A method of manufacturing a semiconductor device, comprising the steps of:

preparing a silicon semiconductor surface which has a predetermined crystal plane orientation;

cleaning the silicon surface with an RCA SC-1 cleaning liquid with a reduced OH concentration; and

forming an oxide film on the cleaned surface by oxidizing the cleaned silicon surface in an atmosphere containing oxygen radicals.

2. A method of manufacturing a semiconductor device, comprising the steps of:

preparing a silicon semiconductor surface which has a (110) plane as a predetermined crystal plane orientation; and

rinsing the silicon surface by the use of H₂O added with deuterium and by applying high frequency vibration to said H₂O to terminate silicon at the silicon surface by deuterium.

3. A method as claimed in claim 2, wherein said high frequency is not less than 500 kHz and the concentration of said deuterium in said H₂O is 0.1 ppm to 1.6 ppm.

4. A method as claimed in claim 2, wherein the rinsing step is carried out in an atmosphere of nitrogen, hydrogen, deuterium or mixture of hydrogen and deuterium.

5. A method as claimed in claim 2, wherein the rinsing step is carried out with the silicon surface being kept isolated from the air.

6. A method of manufacturing a semiconductor device, comprising the steps of:

preparing a silicon semiconductor surface which has a predetermined crystal plane orientation; and

cleaning the silicon surface,

wherein the cleaning step comprises;

a first step of rinsing the silicon surface by using pure water including ozone;

a second step of cleaning the silicon surface by the use of a cleaning solution which includes HF, H₂O with dissolved oxygen of less than 100 ppb, and surface-active agent, providing a vibration of a frequency not lower than 500 kHz;

a third step of rinsing the silicon surface by the use of H₂O including ozone;

a fourth step of cleaning the silicon surface by the use of a cleaning solution including HF and H₂O with dissolved oxygen reduced so as to remove an oxide film; and

a fifth step of rinsing the silicon surface by the use of hydrogen or heavy hydrogen-added H₂O.

7. A method as claimed in claim 6, wherein the fifth step is carried out with vibrations of a frequency not lower than 500 kHz, so as to terminate the silicon surface by hydrogen or heavy hydrogen, respectively.

8. A method of manufacturing a semiconductor device, comprising the steps of:

preparing a silicon semiconductor surface which has a predetermined crystal plane orientation; and

cleaning the silicon surface,

wherein the cleaning step comprises;

processing the silicon surface by the use of a cleaning solution containing HF and H₂O with dissolved oxygen of less than 100 ppb.

9. A method as claimed in claim 8, wherein the cleaning step comprises the steps of:

preparing a cleaning solution which includes HF, H₂O with dissolved oxygen of less than 100 ppb and hydrogen of 0.1 ppm to 1.6 ppm; and

providing the cleaning solution with a vibration of a frequency not lower than, 500 kHz.

10. A method as claimed in claim 8, wherein the cleaning step is carried out without exposing the silicon surface to an air.