Semiconductor device manufacturing method and method for reducing microroughness of semiconductor surface

Abstract

Surface treatment is performed with a liquid, while shielding a semiconductor surface from light. When the method is employed for surface treatment in wet processes such as cleaning, etching and development of the semiconductor surface, increase of surface microroughness can be reduced. Thus, electrical characteristics and yield of the semiconductor device are improved.

1 . A semiconductor device manufacturing method, comprising a surface treatment process in which a surface of a semiconductor material is exposed to a liquid, the surface treatment process being performed in a light shielding state so that the surface of the semiconductor material is not exposed to light. 
     
     
         2 . A method for reducing surface microroughness of a semiconductor surface, comprising a surface treatment process in which a surface of a semiconductor material is exposed to a liquid, the surface treatment process being performed in a treatment chamber shielded from light so that the surface of the semiconductor material is not exposed to light. 
     
     
         3 . A semiconductor device manufacturing method according to  claim 1 , wherein the surface treatment process includes at least one of cleaning, etching, and developing processes. 
     
     
         4 . A semiconductor device manufacturing method according to  claim 1 , wherein the surface treatment process includes a series of steps of cleaning and/or etching, rinsing, and drying, and the series of steps are consistently performed in a light shielding state. 
     
     
         5 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid used in the surface treatment process includes water. 
     
     
         6 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid has a dissolved oxygen concentration equal to or lower than 1 ppm. 
     
     
         7 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid is dissolved with one or both of hydrogen and nitrogen. 
     
     
         8 . A semiconductor device manufacturing method according to  claim 1 , wherein an oxygen gas concentration of an atmosphere of the surface treatment process is suppressed. 
     
     
         9 . A semiconductor device manufacturing method according to  claim 1 , wherein an oxygen gas concentration of an atmosphere of the surface treatment process is suppressed, and the atmosphere includes an inert gas as a main gas species. 
     
     
         10 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid used in the surface treatment process has a pH equal to or larger than 3. 
     
     
         11 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid used in the surface treatment process includes a hydrofluoric acid. 
     
     
         12 . A semiconductor device manufacturing method according to  claim 1 , wherein the liquid used in the surface treatment process includes at least one selected from alcohol, ketone, and a surface active agent. 
     
     
         13 . A semiconductor device manufacturing method according to  claim 1 , wherein a semiconductor surface formed by the surface treatment process has a center line average roughness (Ra) equal to or smaller than 0.1 nm. 
     
     
         14 . A semiconductor device manufacturing method according to  claim 1 , wherein the semiconductor material comprises silicon. 
     
     
         15 . A semiconductor device manufacturing method according to  claim 1 , wherein silicon exposed to the liquid has at least one plane orientation of a (100) plane, a plane offcut by 4° from the (100) plane, a (110) plane, and a (551) plane. 
     
     
         16 . A semiconductor device manufacturing method according to  claim 1 , wherein the light comprises visible light. 
     
     
         17 . A semiconductor device manufacturing method according to  claim 16 , wherein a light source for the light comprises a fluorescent lamp and/or an LED lamp.