| 摘要 |
1,252,814. Bulk effect semi-conductor circuits. INTERNATIONAL BUSINESS MACHINES CORP. 8 April, 1969 [15 July, 1968], No. 17996/69. Heading H3T. [Also in Division G4] In apparatus including a body 10 of bulk effect material having a velocity field characteristic V(E) with sufficient negative differential mobility to satisfy the condition: where # is the average conductivity of the material, a voltage source B applies a D.C. electric field E b to the body which is less than the threshold field necessary to nucleate a high field domain in the body and a source of R.F. signals applies an R.F. field E R.F. to the body, the R.F. field having an angular frequency # such that # G <#<## where ## is the carrier relaxation frequency and # G is a frequency which permits significant electric field rearrangement to take place in the body during that portion of an R.F. cycle where the total field exceeds the threshold value. As shown radio frequency energy from a magnetron or klystron 74 is applied to a waveguide 72 to energize bulk effect devices 10. A standing wave is produced in the guide due to the short circuited end 73. The devices 10, of which any number can be used, each operate in two stable negative resistance conditions (24, 26, Fig. 4, not shown) so as to operate as a data storage memory. Read out is obtained by applying a signal on word line which by means of a PIN diode switch 76 lowers the RF field in the waveguide. If one or other of the devices 10 is in the "1" state (at 26) a voltage drop is sensed on sense line 77; if in the "0" state (at 24) a voltage increase occurs at sense line 77. Writing is achieved by applying a negative or positive bit to bit line 77 to write in "0" or "1" (at 24, 26) respectively. In a modification the waveguide 72 is terminated in an R.F. load (78, Fig. 8, not shown) so that travelling waves are set up in the waveguide. By feeding an R.F. field to the device a double peaked positive and negative current waveform is produced (Fig. 6, not shown). The device then has an average conductivity defined as the average value of this current over one R.F. cycle divided by the bias voltage E b . The device 10 may be of GaAs. The Specification refers to Patents 1,111,187 and 1,070,261. |
