Abstract:
An embodiment of the present invention includes a non-volatile storage unit comprising a first and second N-diffusion well separated by a distance of P-substrate. A first isolation layer is formed upon the first and second N-diffusion wells and the P-substrate. A nano-pillar charge trap layer is formed upon the first isolation layer and includes conductive nano-pillars interspersed between non-conducting regions. The storage unit further includes a second isolation layer formed upon the nano-pillar charge trap layer; and at least one word line formed upon the second isolation layer and above a region of nano-pillar charge trap layer. The nano-pillar charge trap layer is operative to trap charge upon application of a threshold voltage. Subsequently, the charge trap layer may be read to determine any charge stored in the non-volatile storage unit, where presence or absence of stored charge in the charge trap layer corresponds to a bit value.
Abstract:
A memory array is organized into rows and columns of resistive elements and is disclosed to include a resistive element to be read or to be written thereto. Further, a first access transistor is coupled to the resistive element and to a first source line and a second access transistor is coupled to the resistive element and to a second source line, the resistive element being coupled at one end to the first and second access transistors and at an opposite end to a bit line. The memory array further has other resistive elements that are each coupled to the bit line. The resistive element is written to while one or more of the other resistive elements are being read.
Abstract:
Fabrication methods for MRAM are described wherein any re-deposited metal on the sidewalls of the memory element pillars is cleaned before the interconnection process is begun. In embodiments the pillars are first fabricated, then a dielectric material is deposited on the pillars over the re-deposited metal on the sidewalls. The dielectric material substantially covers any exposed metal and therefore reduces sources of re-deposition during subsequent etching. Etching is then performed to remove the dielectric material from the top electrode and the sidewalls of the pillars down to at least the bottom edge of the barrier. The result is that the previously re-deposited metal that could result in an electrical short on the sidewalls of the barrier is removed. Various embodiments of the invention include ways of enhancing or optimizing the process. The bitline interconnection process proceeds after the sidewalls have been etched clean as described.
Abstract:
A method of method of writing to a magnetic memory cell includes selecting a magnetic memory cell of a magnetic memory array to be written to, the magnetic memory cell including a pair of MTJs, and setting a bit line (BL) coupled to the magnetic memory cell to a state that causes current to flow through the pair of MTJs in a manner that causes the direction of current flow through one of the MTJs of the pair of MTJs to be in a direction opposite to that of the other MTJ of the pair of MTJs.
Abstract:
A method of manufacturing a magnetic memory element includes the steps of forming a permanent magnetic layer on top a bottom electrode, forming a pinning layer on top the permanent magnetic layer, forming a magnetic tunnel junction (MTJ) including a barrier layer on top of the pinning layer, forming a top electrode on top of the MTJ, forming a hard mask on top of the top electrode, and using the hard mask to perform a series of etching processes to reduce the width of the MTJ and the top electrode to substantially a desired width, where one of these etching processes is stopped when a predetermined material in the pinning layer is detected thereby avoiding deposition of metal onto the barrier layer of the etching process thereby preventing shorting.
Abstract:
A magnetic random access memory (MRAM) cell includes an embedded MRAM and an access transistor. The embedded MRAM is formed on a number of metal-interposed-in-interlayer dielectric (ILD) layers, which each include metal dispersed therethrough and are formed on top of the access transistor. An magneto tunnel junction (MTJ) is formed on top of a metal formed in the ILD layers that is in close proximity to a bit line. An MTJ mask is used to pattern the MTJ and is etched to expose the MTJ. Ultimately, metal is formed on top of the bit line and extended to contact the MTJ.
Abstract:
Methods of fabricating MTJ arrays using two orthogonal line patterning steps are described. Embodiments are described that use a self-aligned double patterning method for one or both orthogonal line patterning steps to achieve dense arrays of MTJs with feature dimensions one half of the minimum photo lithography feature size (F). In one set of embodiments, the materials and thicknesses of the stack of layers that provide the masking function are selected so that after the initial set of mask pads have been patterned, a sequence of etching steps progressively transfers the mask pad shape through the multiple mask layer and down through all of the MTJ cell layers to the form the complete MTJ pillars. In another set of embodiments, the MTJ/BE stack is patterned into parallel lines before the top electrode layer is deposited.
Abstract:
A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
Abstract:
A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.
Abstract:
A non-volatile magnetic memory element includes a number of layers one of which is a free layer which is graded. The graded free layer may include various elements with each element having a different anisotropy or it may include nonmagnetic compounds and magnetic regions with the non-magnetic compounds forming graded contents forming a unique shape such as cone shaped, diamond shaped or other shapes and whose thickness is based on the reactivity of the magnetic compound.