Writing control method and writing control system of semiconductor storage device, and portable electronic apparatus

• US 20050002263A1
• Filed: 05/19/2004
• Published: 01/06/2005
• Est. Priority Date: 05/20/2003
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Iwata, Hiroshi, Shibata, Akihide, Yaoi, Yoshifumi, Iwase, Yasuaki, Morikawa, Yoshinao, Nawaki, Masaru
• Granted Patent: US 7,050,337 B2
• Time in Patent Office: Days
• US Class Current: 365/230.30
• CPC Class Codes: G11C 16/24 Bit-line control circuits

Abstract

A writing control system providing high-speed writing to a nonvolatile semiconductor storage device, includes (a) a plurality of memory elements each having: a gate electrode provided on a semiconductor layer with an intervening gate insulating film; a channel region provided beneath the gate electrode; a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges, (b) a memory array including a page buffer circuit, and (c) CPU controlling writing to the memory array. The CPU loads a first plane of the page buffer circuit with a first byte of data and writes with the first byte of data stored in the first plane. Further, the CPU writes a second byte of data into the second plane and writes the second byte of data having been stored in the second plane while writing the first byte of data having been stored in the first plane into the memory array.

Claims

1. A writing control method of sequentially writing data into a semiconductor storage device,

the semiconductor storage device including a memory system having:

(a) a memory array having a plurality of memory elements each having;

a gate electrode provided on a semiconductor layer with an intervening gate insulating film;

a channel region provided beneath the gate electrode;

a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and

a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges;

(b) a page buffer circuit including a first plane and a second plane; and

(c) a memory control circuit controlling writing with respect to the memory array and being capable of accessing the page buffer circuit,

the writing control method comprising;

a first step of writing first data into the first plane;

a second step of controlling the memory control circuit to write the first data having been written into the first plane into the memory array;

a third step of writing second data into the second plane while the first data having been written into the first plane is written into the memory array; and

a fourth step of controlling the memory control circuit to write the second data having been written into the second plane into the memory array.

2. The writing control method as set forth in claim 1, further comprising:

a step of initially determining whether the first and second planes are available for user access.

3. The writing control method as set forth in claim 2, wherein:

the determination step reads a status register included in the memory array.

4. The writing control method as set forth in claim 1, wherein:

the third step is performed in a clock cycle immediately following the second step.

5. The writing control method as set forth in claim 1, wherein:

the first and second planes comprise static random access memory.

6. The writing control method as set forth in claim 1, wherein:

a memory functioning member in each memory element further includes a charge holding film extending substantially parallel to a side surface of the gate electrode.

7. The writing control method as set forth in claim 1, wherein:

the semiconductor layer in each memory element has a greater concentration region close to the diffusion region than close to a surface of the semiconductor layer beneath the gate electrode.

8. The writing control method as set forth in claim 1, wherein:

each memory element has an insulating film separating the channel region or the semiconductor layer from a film having a surface substantially parallel to a surface of the gate insulating film to hold electric charge; and

the insulating film is thinner than the gate insulating film and not thicker than 0.8 nm.

9. A writing control system where data are sequentially written into a semiconductor storage device,

the semiconductor storage device including a memory system having:

(a) a memory array having a plurality of memory elements each having;

a gate electrode provided on a semiconductor layer with an intervening gate insulating film;

a channel region provided beneath the gate electrode;

a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and

a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges;

(b) a page buffer including a first plane and a second plane; and

(c) a memory control circuit controlling writing with respect to the memory array and being capable of accessing the page buffer,

the writing control system comprising;

first plane writing means writing a first byte of data into the first plane;

first writing control means controlling the memory control circuit to write the first byte of data having been written into the first plane into the memory array;

second plane writing means writing a second byte of data into the second plane while the first byte of data having been written into the first plane is written into the memory array; and

second writing control means controlling the memory control circuit to write the second byte of data having been written into the second plane into the memory array.

10. The writing control system as set forth in claim 9, further comprising:

determination means initially determining whether the first and second planes are available for user access.

11. The writing control system as set forth in claim 10, wherein:

the determination means include means for reading a status register included in the memory array.

12. The writing control system as set forth in claim 9, wherein:

the second plane writing means writes the second plane in a clock cycle immediately following the control of the memory control circuit by the first writing control means.

13. The writing control system as set forth in claim 9, wherein:

a memory functioning member in each memory element further includes a charge holding film extending substantially parallel to a side surface of the gate electrode.

14. The writing control system as set forth in claim 9, wherein:

the semiconductor layer in each memory element has a greater concentration region close to the diffusion region than close to a surface of the semiconductor layer beneath the gate electrode.

15. The writing control system as set forth in claim 9, wherein:

each memory element has an insulating film separating the channel region or the semiconductor layer from a film having a surface substantially parallel to a surface of the gate insulating film to hold electric charge; and

the insulating film is thinner than the gate insulating film and not thicker than 0.8 nm.

16. A portable electronic apparatus, comprising the writing control system as set forth in claim 9.

17. A writing control system where data are written into a semiconductor storage device,

the semiconductor storage device including a memory system having:

(a) a memory array having a plurality of memory elements each having;

a gate electrode provided on a semiconductor layer with an intervening gate insulating film;

a channel region provided beneath the gate electrode;

a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and

a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges;

(b) a page buffer including a first plane and a second plane; and

(c) a memory control circuit controlling writing with respect to the memory array and being capable of accessing the page buffer,

the writing control system comprising;

first plane writing means writing a byte of data into the first plane by providing a set of first data signals to the memory system;

first writing control means controlling the memory control circuit to write the byte of data having been written into the first plane into the memory array by providing command signals to the memory system, the command signal representing writing from the page buffer to the memory array;

second plane writing means, while the memory control circuit performs writing to the memory array, writing a block of data into the second plane by providing data signals representing a block of data to the memory system; and

second writing control means controlling the memory control circuit to write the block of data having been written into the second plane into the memory array by providing command signals to the memory system, the command signal representing writing from the page buffer to the memory array.

18. The writing control system as set forth in claim 17, further comprising:

determination means initially determining whether the first and second planes are available for user access.

19. The writing control system as set forth in claim 18, wherein:

the determination means include means for reading a status register included in the memory array.

20. The writing control system as set forth in claim 17, wherein:

the first writing control means performs control of the memory control circuit in a clock cycle immediately following writing of the first plane by the first plane writing means.

21. The writing control system as set forth in claim 17, wherein:

the second plane writing means writes the second plane in a clock cycle immediately following control of the memory control circuit by the first writing control means.

22. The writing control system as set forth in claim 17, wherein:

the second writing control means performs control of the memory control circuit in a clock cycle immediately following writing of the second plane by the second plane writing means.

23. The writing control system as set forth in claim 17, wherein:

the first and second planes comprise static random access memory.

24. The writing control system as set forth in claim 17, wherein:

a memory functioning member in each memory element further includes a charge holding film extending substantially parallel to a side surface of the gate electrode.

25. The writing control system as set forth in claim 17, wherein:

the semiconductor layer in each memory element has a greater concentration region close to the diffusion region than close to a surface of the semiconductor layer beneath the gate electrode.

26. The writing control system as set forth in claim 17, wherein:

each memory element has an insulating film separating the channel region or the semiconductor layer from a film having a surface substantially parallel to a surface of the gate insulating film to hold electric charge; and

the insulating film is thinner than the gate insulating film and not thicker than 0.8 nm.

27. A portable electronic apparatus, comprising the writing control system as set forth in claim 17.

28. A writing control system where data are sequentially written into a semiconductor storage device,

the semiconductor storage device including a memory system having:

(a) a memory array having a plurality of memory elements each having;

a gate electrode provided on a semiconductor layer with an intervening gate insulating film;

a channel region provided beneath the gate electrode;

a diffusion region provided on both sides of the channel region, having an opposite polarity to the channel region; and

a memory functioning member, provided on both sides of the gate electrode, having a function of holding electric charges;

(b) a page buffer including a first plane and a second plane; and

(c) a memory control circuit controlling writing with respect to the memory array and being capable of accessing the page buffer,

the writing control system comprising;

first plane writing means writing a first block of data into the first plane by providing a set of first data signals representing the first block of data to the memory system;

first writing control means controlling the memory control circuit to write the first block of data having been written into the first plane into the memory array by providing command signals to the memory system, the command signal representing writing from the page buffer to the memory array;

second plane writing means, while the memory control circuit performs writing to the memory array, writing a second block of data into the second plane by sequentially providing data signals representing the second block of data to the memory system; and

second writing control means controlling the memory control circuit to write the second block of data having been written into the second plane into the memory array by providing command signals to the memory system, the command signal representing writing from the page buffer to the memory array.

29. The writing control system as set forth in claim 28, further comprising:

determination means initially determining whether the first and second planes are available for user access.

30. The writing control system as set forth in claim 29, wherein:

the determination means include means for reading a status register included in the memory array.

31. The writing control system as set forth in claim 28, wherein:

the first writing control means performs control of the memory control circuit in a clock cycle immediately following writing of the first plane by the first plane writing means.

32. The writing control system as set forth in claim 28, wherein:

the second plane writing means writes the second plane in a clock cycle immediately following control of the memory control circuit by the first writing control means.

33. The writing control system as set forth in claim 28, wherein:

the second writing control means performs control of the memory control circuit in a clock cycle immediately following writing of the second plane by the second plane writing means.

34. The writing control system as set forth in claim 28, wherein:

the first and second planes comprise static random access memory.

35. The writing control system as set forth in claim 28, wherein:

the first plane writing means first commands sequential writing of the page buffer by providing command signals to the memory array, the command signal representing sequential writing of the page buffer.

36. The writing control system as set forth in claim 35, wherein:

the first plane writing means specifies the number of bytes of data written into the page buffer.

37. The writing control system as set forth in claim 28, wherein:

the second plane writing means first commands sequential writing of the page buffer by providing command signals to the memory array, the command signal representing sequential writing of the page buffer.

38. The writing control system as set forth in claim 37, wherein:

the second plane writing means specifies the number of bytes of data written into the page buffer.

39. The writing control system as set forth in claim 28, wherein:

the first and second writing control means specify a start address in the memory array.

40. The writing control system as set forth in claim 28, wherein:

a memory functioning member in each memory element further includes a charge holding film extending substantially parallel to a side surface of the gate electrode.

41. The writing control system as set forth in claim 28, wherein:

the semiconductor layer in each memory element has a greater concentration region close to the diffusion region than close to a surface of the semiconductor layer beneath the gate electrode.

42. The writing control system as set forth in claim 28, wherein:

each memory element has an insulating film separating the channel region or the semiconductor layer from a film having a surface substantially parallel to a surface of the gate insulating film to hold electric charge; and

the insulating film is thinner than the gate insulating film and not thicker than 0.8 nm.

43. A portable electronic apparatus, comprising the writing control system as set forth in claim 28.