Ferroelectric register, and method for manufacturing capacitor of the same
View Patent ↗The present invention discloses a ferroelectric register and a method for manufacturing a capacitor of the same. The ferroelectric register is configured to reduce probability of data storage failure due to a weak state capacitor, by connecting a plurality of capacitors in parallel in a ferroelectric capacitor unit for storing data, instead of using a single capacitor, thereby improving storage reliability and stability. In addition, the ferroelectric register obtains a data sensing margin by pumping a cell plate signal into not a power voltage level but a pumping voltage level.
1. A method for manufacturing a ferroelectric capacitor of a ferroelectric register which includes a pull-up switch for outputting a power voltage when a pull-up enable signal is activated; a pull-up driving unit for receiving the power voltage from the pull-up switch, and for pulling up a voltage of a data storage node to the power voltage; a write enable control unit for transmitting a differential data to the data storage node according to a write control signal; the ferroelectric capacitor connected between the data storage node and a plate line and storing the differential data when a cell plate signal from the plate line is activated; a pull-down switch for transmitting a ground voltage to the data storage node when a pull-down enable signal is activated; and a pull-down driving unit for receiving the ground voltage from the pull-down switch and for pulling down the voltage of the data storage node to the ground voltage, comprising:
a first process for forming at least two bottom electrode layers commonly connected to the data storage node;
a second process for forming a ferroelectric layer on the at least two bottom electrode layers; and
a third process for forming a top metal layer receiving the cell plate signal on the ferroelectric layer.
2. The method of claim 1 , wherein the two bottom electrode layers correspond to the ferroelectric capacitor and another ferroelectric capacitor which are connected in parallel.
3. The method of claim 2 , wherein the ferroelectric capacitor and the another ferroelectric capacitor form a ferroelectric capacitor unit within the ferroelectric register.
4. The method of claim 3 , wherein, within the ferroelectric capacitor unit, the ferroelectric capacitor and the another ferroelectric capacitor are connected in parallel between the data storage and the ground voltage.