Array of multi-bit ROM cells with each cell having bi-directional read and a method for making the array
    1.
    发明授权
    Array of multi-bit ROM cells with each cell having bi-directional read and a method for making the array 有权
    具有每个单元具有双向读取的多位ROM单元的阵列和用于制作阵列的方法

    公开(公告)号:US07012310B2

    公开(公告)日:2006-03-14

    申请号:US10642078

    申请日:2003-08-14

    申请人: Dana Lee Bomy Chen

    发明人: Dana Lee Bomy Chen

    摘要: A array of multi-bit Read Only Memory (ROM) cells is in a semiconductor substrate of a first conductivity type with a first concentration. Each ROM cell has a first and second regions of a second conductivity type spaced apart from one another in the substrate. A channel is between the first and second regions. The channel has three portions, a first portion, a second portion and a third portion. A gate is spaced apart and is insulated from at least the second portion of the channel. Each ROM cell has one of a plurality of N possible states, where N is greater than 2. The state of each ROM cell is determined by the existence or absence of extensions or halos that are formed in the first portion of the channel and adjacent to the first region and/or in the third portion of the channel adjacent to the second region. These extensions and halos are formed at the same time that extensions or halos are formed in MOS transistors in other parts of the integrated circuit device, thereby reducing cost. The array of ROM cells are arranged in a plurality of rows and columns, with ROM cells in the same row having their gates connected together. ROM cells in the same column have the first regions connected in a common first column, and second regions connected in common second column. Finally, ROM cells in adjacent columns to one side share a common first column, and cells in adjacent columns to another side share a common second column.

    摘要翻译: 多位只读存储器(ROM)单元的阵列位于具有第一浓度的第一导电类型的半导体衬底中。 每个ROM单元具有在基板中彼此间隔开的第二导电类型的第一和第二区域。 通道在第一和第二区域之间。 通道具有三个部分,第一部分,第二部分和第三部分。 门间隔开并与通道的至少第二部分绝缘。 每个ROM单元具有多个N个可能状态中的一个,其中N大于2.每个ROM单元的状态由存在或不存在在通道的第一部分中形成并与通道的第一部分相邻 第一区域和/或与第二区域相邻的通道的第三部分。 在集成电路器件的其他部分的MOS晶体管中形成扩展或光晕的同时形成这些扩展和光晕,从而降低成本。 ROM单元的阵列被布置成多个行和列,其中同一行中的ROM单元的门连接在一起。 同一列中的ROM单元具有连接在公共第一列中的第一区域和连接在公共第二列中的第二区域。 最后,一侧的相邻列中的ROM单元共享一个共同的第一列,另一侧的相邻列中的单元格共享第二列。