Patent · US Expired

Semiconductor device and manufacturing method thereof

US6281558A · kind A · utility

22Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 30, 1998
Grant dateAug 28, 2001
Priority date
Expiry dateJul 30, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/0144

Abstract

A high-voltage element (H)to which a high gate voltage is applied, and a low-voltage element (L) to which a low gate voltage is applied, are formed in a semiconductor substrate (1). Bird's beaks (8, 18) are formed in gate insulating films (7, 17) by thermal oxidation. Since a gate electrode (9) of the element (H) has a shorter gate length than a gate electrode (19) of the element (L), the ratio of the bird's beak in the gate insulating films (7, 17) is small in the element (L) and large in the element (H). Therefore, the element (H) has a high breakdown voltage and less aged deterioration, leading to long lifetime. The element (L) has a high current driving capability to produce high-speed operation. Thus, long lifetime, high operation speed and easy manufacturing steps are realized at the same time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.