CS201113B1 - Semiconductor device particularly the semiconductor diode with ammeliorated permeability characteristics - Google Patents

Abstract

The semiconductor diode, for use as a rectifier or radiation source, has its forward bias properties improved by having an n+p+n- or p+n+p- structure. The current flowing through the highly doped n+p+ or p+n+ junction when this junction is reverse biased is essentially a tunnel current. The differently doped layers are produced by ion implantation. This diode structure considerably reduces the forward bias voltage by improvising the special relationship between space charge regions and makes the diode particularly suitable for electronic wrist watches.

Description

Vyiález relates to semiconductor devices, in particular semiconductor diodes having improved OHA ^ ^r ^ fi ^ akterd cri ^ C ^ u ^{p p} ro ^ rspιutnocti RAIT I ^r o ^ L ^ fruit deflector means or the ^{P L} ov ^ ^ý .ovodLc transmitter - radiation and semiconductor indicator emitting radiation ·

It is known that in the PN junction there is a diffusion voltage due to the diffusion of holes from the - P to - N region and the electrons from the N to P region at equilibrium

where N koncentraci denotes the acceptor concentration in the P region, to the Boltzmann cointant, T T temperature, q the elementary charge, N β of the donor concentration on the N side, and n teoret theoretic ηοοη ^ ηο! of electrons and holes of pure ideal semiconductor without doping · This diffuse voltage Vp is polarized so that currents induced by it counteract the diffuse currents (plus on the N, m.mua and on the rounding P) When connecting an external U which is polarized opposite to the diffuse The voltage VD> is changed by the suppression of diffuse currents - it is the forward direction. In martial poling as with the diffuse voltage V-p, the external voltage for suppressing diffuse currents will increase - this is the reverse direction. In the simplest case, sufficient to describe the invention, it is possible to express the current-tapping characteristic of diffuse currents.

201 113

201 113 equation

wherein J denotes current density _fl naeyoení which HAVIS only on the properties of the semiconductor rather than on the connected voltage. The greater the width between the rolling band and the conducting band of the semiconductor, the smaller the values j _fl and ^ · The small theoretical concentration of electrons and holes of pure ideal semiconductor without doping n ^ means a large diffusion voltage. Only at higher flux voltages with a large width between the valence band and the conductive band reach the same current density values J, as in semiconductors in the smaller width between the valence band and the conductive band. The so-called threshold voltage, ie. the required voltage across the semiconductor diode at the PN junction in the forward direction for current densities of greater than -3-2 or equal to 5 x 10A cm is thus determined essentially by the type of semiconductor material used.

It is known that semiconductor rectifiers whose action is to create a PN junction or radiation emitting diodes need a voltage to operate, which is determined by the type of semiconductor material and can practically be little influenced by the choice of doping concentration N _A and Np,

For semiconductor rectifiers in which the rectifying effect is not caused by the PN junction but by the Schottky junction, it is known to achieve improved throughput characteristics, i.e., an increase in the throughput current at low throughput voltages by the advantageous choice of material combinations, e.g.

A disadvantage of the known semiconductor devices with PN junction, especially diodes, is that they have relatively high forward-voltage voltages and a large voltage drop required for forward-mode operation. Reducing such energy losses means extending the application possibilities for radiation emitting diodes in those devices whose energy needs must be met by the battery, such as watches, handheld computers, etc., while increasing their efficiency.

The purpose of the invention is to provide a semiconductor device with a substantially lower voltage and energy loss, in particular for use as radiation emitting indicators in wristwatches which must be operated with monocouples.

It is an object of the present invention to improve the permeability characteristics of a semiconductor arrangement, in particular of a light emitting semiconductor diode and a semiconductor rectifier, by corresponding spatial arrangement of the spatial charge bands at the PN junction,

This problem is solved by a semiconductor arrangement in which, due to the spatial arrangement of the spatial charge bands at the PN junction, the original diffusion voltage Vp does not counteract the external voltage applied to the semiconductor device in the forward direction, but

201 113 of the semiconductor device itself compensates for the original long-voltage voltage V _D · This achieves a steeper increase in the throughput current at the throughput voltage than in a simple transition ·

According to the invention, this suitable spatial arrangement of the spatial zones. ^cartridges, for ^instance ec ^h ODU ^p N ^d os ^oh no structures II ⁺ P ⁺ N no ^b of stírukturami P ^{+ h +} P · High to * Tovan ^E Go - N + P ⁺ _9, in addition ^P and ^{DE p4J} with ^p s zatlení tfohto ' structures in ^p ro ^p oral ^- direction (when stru ^ urach l ^ P ⁴ is ^p lus to H ^4, a minus ^Nj when structures ^{р +} К * К is ^ nus ^P4 _t plus is. ^p) operates the shutter ^of inxém direction. Diftoní high voltage ^to tovanýc ^{h BC} echo ^dU is directed in the structures ^P Roti dfúznímu voltage of the prostate; orov ^of follow-ch ^{p4 ft} ^ N ^ The situations ^4p transitions.

^p ccording to the invention are high ⁱⁿ Tovan ^s přeciio ^ n ^{+ p +, p} OPŘ ^Ip and ^{dt р + н +} vytvoiřeny such that during operation of these transitions in the reverse direction, i.e. in the operation of the entire structure К ^{+ р +} П 9 ^p O ^P :: pa ^dt P ⁴ ^ ⁴ ? ^p in the oral direction _{T of} the barrier rou ^{p d} tovanych transitions high ^to substantially tunnel current. Highly subsidized transitions thus act as tunnel diode transitions. ^É voltage barrier structure is determined by ^{a straight} ec ^{h dy P4} H ^or ^ and ^ N ^4p, navazujícdmi on highly doped transitions. Propuutnooti improved characteristics are achieved by a tunnel current high -dotovaných obbasti transitions in the middle, for example, ^{p +} region of the structure ^- N ^{+ P +} tf not the area ^{b 4} struktíuy N ^{'p +} n ^{+ p,} form additional mjoritní carrier. In the known pn junctions without highly doped additional bandwidth, for example at the crossings P ⁴ N N No ^b of ^{4p, -} the flow is set ^to the AC crowd ^Z e ^ f ^{di of the} Zn in ^the tension .se ^ s ^ d ^ spatial displacement distribution of electrons and holes by the current flow is reduced by the voltage connected outside, ^p s zanemání other example ^of ium losses. For drudur according vyndezu the current load structure in the forward direction formed in the central area of the additional carrier rábojú same ^type JA ^to the ^SRT OC ^and n ^{Im t} o is Kiryu in odasti ^p4 stiudury N ^4p4 ® and elektaony 'in onasti N ⁴ structure ^p4 ^ ^4p . ^{- T} m is changed ^ i ^ E ^: s ^ d toytek NIH ^overloading on the whole structure and -The Rech ^{1 P} ^ o ^d u K ^{p4 -} REW · N ^{+ P.} However, this phenomenon can změěd.tj MLA grant ions diffuse marry off first small-to-voltage structure, that then, when a constant outer napěěí, additional current, which means an additional increase in the hole with the ob and P ⁴ and N ^p4p4 druktury in eledronů obl.aati N ⁴ structures ^{p4p4p, aW} . Finally set crowd ^P s which is the voltage ^{drop of the} íový ^of TE ^to the structure to the surrendered only Ješ napěíovým UB ^ ^y ^ tkem on high-linking ^{REC h} ODU t ≤ ^4, res ^p. and on the remaining zone of the charge islands in the impact ^p and ^b respectively. N, how ¹ losses ¹ on track supports. Considering the mutual polarization of these stresses, N ⁴ P ⁴ N, res ^p is obtained for the entire structure. ^{p4 4p} N, ^P s zaHžení proutóem smaller threshold 'voltage than ^p ro ^p Rech jetoráuctó ^{soil p4} N, respectively. _ ^p4p .

It is expedient to produce the semiconductor device according to the invention by ion-doping. It is particularly advantageous thus to create a highly doped layer zlepšuuící otaMrartearLdiku propiusnodi, i.e. with ^p řechodu ^p ^ T E ^{D BC} odastí ^p4 layer ^of up eoho ^{M4P d} u e p ^{of d-OBn} Asti N ⁴ P vrdvu ^fourth . This method allows creating ^at ZKE spatial dimensions for potíebró -tunelo

201 ИЗ effect of high-doped transitions · Linting also allows to make the additional high-doped layer as thin as possible, which is important, for example, for radiation emitting diodes to prevent additional loss of radiation generated at P * M or · H ⁺ P tier ·

The advantages of the semiconductor device according to the invention are that the forward voltage is reduced and the energy losses that occur in the operation of semiconductor diodes, such as semiconductor rectifiers and semiconductor emitters, are reduced.

At the same time, the stability of these components is increased, since their heat load is also reduced as a result of reduced energy losses. · Due to low forward voltage, the field of application of these semiconductor devices will increase, for example semiconductor emitters become more suitable for wristwatches.

The invention will be explained in more detail below with reference to the accompanying drawings, in which FIG. 1 shows the semiconductor device according to the invention, FIG. 2 shows the spatial distribution of the doping concentration in the semiconductor device and FIG. equipment·

For example, the structure K ^ P ^ K has been chosen. · The coordinate j (Fig. 1) denotes the distance perpendicular to the surface of the semiconductor body to the volume of the body · The surface lies at x 0 · Production of the K ⁺ P * K structures by distributing the doping concentration according to FIG. 2, ion doping of the receptors is effected, whereby the concentration of the receptors дd is generated up to a depth x ₂ in a semiconductor body with a doping concentration of Npg. а Кд as well as the spatial extension of the transition

K ⁺ P * is selected so that when the U voltage is applied to the K ⁺ PtCI structure in the forward direction (positive pole to K ⁴ , negative pole to K), this transition K * P ⁺ acts as a tunnel diode and the current induced by this voltage Thus, in this K ⁺ P ⁺ transition, essentially the tunnel current 1 ^ · The concentration а Кд as well as the spatial extension of the K ⁺ P ⁺ transition is chosen in a known manner as for tunnel diodes ·

Fig. 3, which schematically depicts the spatial progression of the strips, ie the energy of the electrons E as a function of the depth x, shows the function of the structure K ^ P ^ K in the forward direction polarization ·

The whole structure of N ⁺ P ⁺ N has a resulting diffuse voltage equal to the difference of the diffuse voltage Vp of the P ⁺ K transition and the diffuse voltage of the N ⁺ P1 transition Because the n + p '*' transition acts as a tunnel diode, already a large reverse current of the N ⁺ P ⁺ transition, which is essentially a tunnel current I _and j · Additional konoentraoe holes. resulting from this current in the P ^{+ region} , by its action of the space charge, it compensates for the partially diffuse voltage V ^. whereby the already explained phenomenon can be used in an amplifying way · Total current transmitted through the structure κ + ρ ^ ΙΤ

201,113 is equal to I * _T · P ⁺ V obharti and in the N continues as a diffusion current of holes and electrons at the most frequent types of semiconductors, especially však'jako electron diffusion current 1 ^ (S ^de rami recombination in ^{the p +} encircled in Fig 3 · The cognitive effect of the concentrations of holes formed by I _and j. In the region of ^{p +} to the diffusion voltage VD, the voltage at ^the transition of E * P ⁺ and ^{p +} H leads to an inexpensive expansion of the region in the region ^of the transition voltage E * P ⁺ and ^{p +} H. N, ^{P +} and H ⁺ is so large that it is possible to produce a ^{p p} ASEM rostorov it ntooje Přech ^é ^ u n ^{+ p +} and ^{p +} N ^ Dalja requirements emerge. - from speciátaí ^ cases poiuiií) with diodes vykajících radiation mtuí be for instance χ, namely the extension zone of the Ti n ⁺ what nejmee ^, and ^would remove pMdavně losses Emsey raging in ^- Dusla ^dk u ^b sorption and size of the zone of ^{P +,} i.e. x ₂ - x ^, mission to be - so ^- large,. and ^could not as ^p rovést; jÚpXiaějáí recombination e ^ KTron Draw it dif ^p rou ^d ua ^ mM uvd.tř obi ^ at ^ X ^{p +} ·

Claims (2)

1 · a semiconductor device, particularly polovodičová- diode with improved CTA ^ rakterlstikcu proputno ^ i ^P ro poráití as ^ lovod ^ AC regulate ^No. Neto semi-above ^VF í ^lac Zaret, vyzm-bore formed in, ^that E mu stiiukturu respektdLve ^{p +} N ^{+ p,} with differently doped layers, wherein at cdpocídajííí.kcntcetra ¢ and doping - a highly doped geomeerickych dimensions ^eg from ec ^{h u -} n ^{+ p + p4} respektdlve H ^{4, the} flow during operation of - přechodů.při reverse tunnel current load · A semiconductor device according to claim 1, characterized in that at least one of the differently doped layers is made by ion doping ·