微波ECR等离子体刻蚀系统

Microwave Electron Cyclotron Resonance Plasma Etching System

研制成功了一台微波电子回旋共振等离子体刻蚀系统。该系统采用微波通过同轴开口电介质空腔产生表面波 ,由Nd Fe B永磁磁钢形成高强磁场 ,通过共振磁场区域内的电子回旋共振效应产生大面积、均匀、高密度等离子体。利用该系统实现了SiO2 、SiN、SiC、Si等材料的微细图形刻蚀 ,刻蚀速度分别为 2 0 0nm/min ,5 0 0nm/min ,4 0 0nm/min ,70 0nm/min ,加工硅圆片Φ2 0 0mm ,线条宽度 <0 3μm ,选择性 (SiO2 、Si) >2 0 ,剖面控制 >83° ,均匀性 95 % ,等离子体密度 2 0× 10 11cm-3 。电离度大(>10 % ) ,工作气压低 (1Pa～ 10 -3 Pa) ,均匀性好 ,工艺设备简单 ,参数易于控制等优点。

A microwave ECR (Electron Cyclotron Resonance) placma etching system was successfully developed.This system generates surface wave by means of the transmission of microwave in the open coaxial dielectric chamber and high magnitude magnetic field by Nd Fe B permanent magnets.Large area plasma with high density and good uniformity is generated by the electron cyclotron resonance effect in the magnetic field.With this system,etching ptofiles of SiO 2,SiN,SiC and Si were obtained at the rate of 200 nm/min,500 nm/min,400 nm/min,700 nm/min respectively.Some experimental parameters are as follows;the Si wafer is 200 mm in diameter;the line width is no more than 0 3 μm;selectivity betwwen SiO 2 and Si is no less than 20;aspect ratio is no less than 83 degrees;the uniformity is as high as 95%;the density of plasma is 2 0×10 11 cm -3 .