DE2159182A1 - Vibrating element - Google Patents

Description

MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. Osaka, Japan

The invention relates to a semiconductor vibrating element with the structure pnpn or npnp.

With the conventional vibrating elements, vibrations are generally triggered when there is a negative resistance appears, but is. their stability is low and their vibration characteristics cannot be influenced from the outside.

The invention is intended to eliminate these deficiencies and a vibrating element is to be created whose vibrational state is stable and can be influenced from the outside "

The invention has the task of creating a vibrating element

fen, consisting of (a) a semiconductor body with at least one Surface area, (b) a first and a second area whose Conductivity type is opposite to that of the semiconductor body, these areas being formed in the surface area, (c) a third area formed in the second area, the

Leadership type

209835/064 1

Conductivity type is opposite to that of the second area, (d) to the semiconductor body or to the first and to the third area connected electrodes and (e) gate voltage means for Applying a positive bias voltage to the electrode of the semiconductor body and to the electrode of the first region with respect to the the third area for the production of vibrational phenomena between the electrodes of the first and third area.

The vibrating element according to the invention will now be described with reference to the accompanying drawings. Show in it:

Figo 1 is a schematic cross-sectional view of an embodiment of the invention Schwingelementsf

JIg. 2 shows a current-voltage characteristic curve of the element of ilg. 1; and

ilg. 3 shows the oscillation range of the in Jig. I shown item.

In lig. 1 is an embodiment of the vibrating element shown, in which an n-type semiconductor body 1 is provided, the also has two p-regions 2 and 3, which are in the semiconductor body 1, an η region 4> that in the p region 3 is formed, electrodes 5, 6 and 7> those with the n-area 4, the p-region 2 or are connected to the semiconductor body 1, and an insulating layer 8.

The semiconductor body can consist of one of the usual Materials such as Si, · Ge, GaAs or GaP are made. To the For the purpose of the description, it is assumed that the semiconductor body 1 is silicon, for example. Also can the conductivity types are in each case opposite to that in this embodiment, without this affecting the principle of the invention.

The p-regions 2 and 3 become in the n-type silicon body 1 formed by a common diffusion process. The n-region in the p-region 3 is then generated in a similar manner. In the The insulating layer θ is usually silicon oxide. The electrodes 5 »6 and 7 are with the η-areas and with the p-area of the cell in ohmic contact. To generate vibrations

209835/0641

generation according to the invention, it is necessary that the p-regions 2 and 3 as well as the n-area 4 in the one surface area of the Semiconductor body 1 are formed.

The current-voltage characteristic between the electrodes 5 and 6 is that shown in FIG. 2, with the forward direction then is set when the electrode 6 is positive. In the gate direction a negative resistance is obtained and a high breakdown voltage can be obtained in the reverse direction.

With regard to the negative resistance, it should be noted that the voltage V ₊ depends on the distance L between the p-regions 2 and 3 and on the concentration of impurities in the p-regions. With small values for L, Y ^ assumes small values, and this is also the case when the contaminant concentrations in the n and ^

p-ranges are high.

If a forward bias voltage is now applied between the electrodes 5 and 6, while ^{a positive bias voltage is applied to the electrode 7 i n} with respect to the electrode 5, then V ₊ , assumes high values and at the same time oscillation phenomena can be observed, as shown in FIG. 3 are shown. The oscillation frequency can change with L and values in the range from a few hundred kilohertz to a few tens of megahertz can be observed.

If the bias voltage applied to the electrode 7 is increased, then V ₊ also increases further and the oscillation range is reduced and finally disappears. The oscillation phenomena Video- ä therefore be influenced by the bias of the electrode. 7

An arrangement embodying the invention is now intended be concretized.

In an n-silicon single crystal, the in Fig. 1 shown p-regions boron diffused. Then becomes the. Formation of an η-area phosphorus diffuses in. To the concerned Areas are provided with aluminum electrodes, which represent the electrodes 5, 6 and 7 shown in the drawing. If you lay now biases in such a way that the electrode 6 is positive with respect to the electrode 5 and that the electrode 7 is positive with respect to the

electrode

209 835/0641

Electrode 5 is positive, vibration phenomena such as the shown in Fig. 3 on.

In this case, the distance L was 7 µm and
Oscillation frequency was 1 MHz. It was observed that the
Vibrations stop when the gate voltage for the electrode 7
Assumes a value of 14 V.

As is apparent from the above description, the invention provides a vibrating member which is more stable in one state Vibrations can be operated and that is controllable at the same time. The device according to the invention can therefore, for example for switching purposes, for generating vibrations, for modulation or for Similar purposes can be used and is technically very versatile.

Claim

20 9 83 5/06 41

Claims (1)

Pat ie η t an s τ> r u ο H Schwingeleaent, characterized by [a] a semiconductor body (1) with at least one surface area, [b] a first and second area (2, 5) formed in the surface area of opposite conductivity β ty ρ as the semiconductor body (1) » l_c] a third area formed in the second area (3) (4) Clay of the opposite conductivity type to the second region (3) »[d] ait the semiconductor body (1) relate to the electrodes (5, 6,7) connected to the first and third regions (2, 4) and [e] biasing means for applying a po ei ti ve η bias voltage to the electrodes (7j 6) of the semiconductor body β (1) and the first Area (2) with respect to that of the third area (4) for causing vibration phenomena between the electrodes (6 | 5) of the first and third regions (2, 4). Blank page