Unlock instant, AI-driven research and patent intelligence for your innovation.

Dyamic RAM

A technology of capacitors and substrates, applied in the field of DRAM, can solve the problems of out-diffusion and large out-diffusion

Inactive Publication Date: 2004-07-21
INFINEON TECHNOLOGIES NORTH AMERICA CORPORATION
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Unfortunately, this thermal cycling can result in a larger than desired amount of outdiffusion due to the higher temperature and longer thermal cycle time
Therefore, excessive outdiffusion can result
This excessive outdiffusion, together with possible mask misalignment in gate formation, can lead to insufficient gate channel length for efficient operation of the transistor

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Dyamic RAM
  • Dyamic RAM
  • Dyamic RAM

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0020] now refer to Figures 1A to 1L , described for forming figure 2 The method of dynamic random access memory cell 3 shown in . The cell 3 comprises a field effect transistor 4 , a source / drain region 5 of which is conductively connected to a storage capacitor 6 via a buried strap, or connection region 7 . As will be described, the region within the semiconductor substrate in which the buried strap 7 is located is formed after formation of the STI without using lithography and the strict alignment requirements associated with this lithography.

[0021] In more detail, refer to Figure 1A , providing a semiconductor substrate or body 10 in which deep trenches 12, here P-type doped silicon, have been formed. Formed near the lower portion of the trench 12 using conventional processes is N + Doped region 19. Formed in the deep trench 12 using conventional processes are first and second doped polysilicon materials 14, 16 which together provide for the capacitor 6 ( figu...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A method of forming a dynamic random access memory cell in a semiconductor substrate. The cell has a transistor in an active area of the semiconductor substrate electrically coupled to a storage capacitor through a buried strap or coupling region. The method includes forming an electrode for the capacitor in a lower portion of a trench in the semiconductor substrate. The method is used in a variety of applications including formation of the buried strap used to electrically connect the capacitor and the transistor and formation of a vertical gate channel for the transistor of the cell.

Description

technical field [0001] The present invention relates generally to dynamic random access memories (DRAMs) and, more particularly, to DRAMs having buried capacitors as their storage elements. Background technique [0002] As is known in the art, it is often desirable to form regions of semiconductor devices below the surface of (ie, buried under) the surface of a semiconductor substrate (ie, body). More specifically, it is often necessary to form a first region within a semiconductor substrate and below the surface of such a substrate in alignment with a second region also disposed below the surface of the substrate. Generally, photolithography is used to form the first region. However, in order to form this 1st region, the mask used in the lithography process must be properly aligned with the buried and thus superficially invisible 2nd region. Imprecise and improper mask alignment can lead to defects. [0003] For example, in a DRAM cell with a buried trench capacitor conn...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01L21/302G11C11/413H01L21/3065H01L21/8242H01L27/108
CPCH01L27/10876H01L27/10861H01L29/1037H10B12/038H10B12/053G11C11/413
Inventor U·格吕宁
Owner INFINEON TECHNOLOGIES NORTH AMERICA CORPORATION