公开(公告)号：JPH0669463A

公开(公告)日：1994-03-11

申请号：JP18449093

申请日：1993-06-28

Applicant: ST MICROELECTRONICS SRL

Inventor： GHIO EMILIO GIAMBATTISTA ,  MERONI GIUSEPPE ,  RE DANILO ,  BALDI LIVIO

IPC: G11C17/12 ,  H01L21/8238 ,  H01L21/8246 ,  H01L27/092 ,  H01L27/112

Abstract: PURPOSE: To obtain a ROM matrix whose cell has the junction of diffused parts with concentration gradients by a method wherein ions sufficient to reverse the conductivity-type of a part of a drain region are implanted and diffused and the drain region is decoupled from a channel region. CONSTITUTION: A gate oxide layer 2, a single cell gate electrode 3 and drain regions 4 and 5 are formed in a semiconductor substrate region 1 having the p-type conductivity. A part of the drain area of a programming cell to which a current is not applied is restricted by a photoresist mask M1. Phosphorus ions are diffused through the aperture of the photoresist mask M1 and boron ions are implanted. The conductivity type of a region 6 between programming channel and drain regions is reversed. Then a photoresist mask M2 is formed, drain area of the memory cell is masked and arsenic ions are implanted through the aperture.

公开(公告)号：DE69225700D1

公开(公告)日：1998-07-02

申请号：DE69225700

申请日：1992-10-01

Applicant: ST MICROELECTRONICS SRL

Inventor： GHIO EMILIO GIAMBATTISTA ,  MERONI GIUSEPPE ,  RE DANILO ,  BALDI LIVIO

IPC: H01L21/8246 ,  H01L27/112

公开(公告)号：DE69225700T2

公开(公告)日：1998-09-24

申请号：DE69225700

申请日：1992-10-01

Applicant: ST MICROELECTRONICS SRL

Inventor： GHIO EMILIO GIAMBATTISTA ,  MERONI GIUSEPPE ,  RE DANILO ,  BALDI LIVIO

IPC: H01L21/8246 ,  H01L27/112