Emerging memories

Which material is widely used as the tunnel barrier in MRAM magnetic tunnel junctions (MTJs) and gives a large tunnel magnetoresistance ratio?

  1. AMagnesium oxide (MgO)
  2. BCopper
  3. CPolycrystalline silicon
Show answer and explanation

Answer: A. Magnesium oxide (MgO)

Using crystalline magnesium oxide (MgO) as the tunnel barrier causes electrons with a particular spin to tunnel selectively, giving a very large tunnel magnetoresistance ratio. This greatly increased the resistance difference between 0 and 1 and greatly improved the performance of MRAM and hard-disk read heads.

Practice this topic Back to topic

More Emerging memories questions

  1. In ReRAM, what is the initialization step called in which a relatively high voltage is first applied to form a conductive filament?
  2. Which is a characteristic of SOT-MRAM?
  3. Which is one reason MRAM is attracting attention as embedded non-volatile memory for microcontrollers and similar chips?
  4. In MRAM, what problem tends to arise if the storage element (MTJ) is made too small?
  5. Why have MTJs with magnetization perpendicular to the film plane (perpendicular MTJs) become mainstream in recent STT-MRAM?