Abstract: Each memory cell of an electrically-programmable semiconductor memory has a field-effect transistor with a charge-storage region. Efficient and fast injection of hot carriers into the charge-storage region is achieved by vertical punch-through of a depletion layer to a buried injector region, by application of programming voltages to a control gate and to the surface of the punch-through region. Non-injected carriers are removed via at least the transistor drain during the programming. A well-defined punch-through region can be obtained with a higher-doped boundary region at at least one side of the punch-through region to restrict the lateral spread of the depletion layer(s) and prevent parasitic connections. This permits closer spacing of the injector region to other regions of the memory cell, e.g. source and drain regions, and the injector region may adjoin an inset insulating field pattern.

Abstract: An integrated circuit includes a memory having cells arranged in rows and columns, each cell having transistor being connected between two bit lines and having a current channel, a control gate and a charge-storage region therebetween, neighboring cells in a same row having a bit line contact in common, and control gates of transistors in a row being connected to a same word line, wherein each transistor has in a substrate of a first conductivity type a source region, a drain region and an injector region of a second conductivity type and mutually separated from each other, the injector regions of the transistors in a first row being controllable via the bit line contacts of the transistors in a second row adjacent to said first row. Preferably, at least one source region, at least one drain region and at least one injector region that are connected to a same bit line contact form a coherent region, e.g. a well, in the substrate. Preferably, the first and second row have the word line in common.