Electron‐beam direct writing system EX‐8D employing character projection exposure method
Electron‐beam direct writing system EX‐8D employing character projection exposure method
复制标题
采用字符投影曝光法的电子束直写系统EX-8D
DOI：
10.1116/1.586984
复制
发表时间：
1993
影响因子：
1.4
通讯作者：
Hashimoto Susumu
中科院分区：
文献类型：
--
作者：
K. Hattori;R. Yoshikawa;H. Wada;Hideo Kusakabe;T. Yamaguchi;S. Magoshi;A. Miyagaki;S. Yamasaki;T. Takigawa;M. Kanoh;Shinsuke Nishimura;H. Housai;Hashimoto Susumu
本文介绍了一种用于0.15 μm级超大规模集成电路图形制作的电子束直写系统，该系统在传统的变形状电子束方法的基础上，采用了字符投影方法。该系统是我们的可变形状梁机的修改版本。电子光学系统采用三级八极偏转器，视场为2 mm，并安装了用于字符投影的孔板交换机构。物镜透镜系统的设计使得光束分辨率为0.04 μm。以0.15 μm设计规则写入1G动态随机存取存储器图案的优化研究表明，优选的字符大小和数量分别为2.5 μm和48。该系统的写入速度设计为110 s/片，利用存储单元和外围电路的字符。提出了一种先进的束流密度和字符尺寸、方向和位置的束流校准方法。这种方法有效地调整电流密度为每个字符是相同的晶圆上。通过分析得到的光束强度分布，精确地校正了光束位置。
An electron‐beam direct writing system which adopts character projection methods in addition to conventional variable‐shaped beam methods, has been constructed for 0.15 μm class ultra‐large scale integration pattern fabrication. This system is a modified version of our variable‐shaped beam machine. The electron optical system adopts a three stage octapole deflector for a 2 mm field and installs an aperture plate exchange mechanism for character projection. The objective lens system was designed so that the beam resolution is 0.04 μm. An optimization study to write a 1G‐dynamic random access memory pattern with 0.15 μm design rules showed that a preferable character size and number are 2.5 μm and 48, respectively. The writing speed of this system is designed to be 110 s a chip, using the characters for memory cells as well as peripheral circuits. An advanced beam calibration method has been developed for beam current density and for character size, direction, and position. This method effectively adjusts the current density for each character to be the same on wafers. The beam position is accurately corrected by analyzing the obtained beam intensity distribution.