CN1523642A - Method for reducing electronic excitation energy loss during actions between various particle beams and objects by forming dynamic quasi-neutral particle beam mode - Google Patents

Abstract

A method for reducing electronic excitation energy loss by forming dynamic quasi-neutral particle beams is that when a particle beam is applied to a selected action zone of an object, an auxiliary radiation beam is added to the said action zone, nearly parallel to the particle beam. Since the said radiation beam accelerates conduction electrons or generates new conduction electrons moving on nearly the same direction, the charged particle beam becomes dynamic quasi-neutral particle beam greatly reducing electronic excitation energy loss between the particle beam and object action.

Description

Form dynamic quasi-neutral bundle mode and reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent

Technical field

The present invention is a kind of method that dynamic quasi-neutral bundle mode reduces the electron excitation energy loss that forms, when the material that is applied to all types of target thing when charged particle beam need reach many processing, production and analysis purpose, reduce the electron excitation energy loss of the particle beams in the zone of action on the object.

Background technology

Charged particle beam is used on the various materials to reach the purpose of many processing and analysis always.For example, with ion implanter may impurity is injected the regular works of every day in the manufactory that the semiconductor-based end is a manufacturing very lagre scale integrated circuit (VLSIC) on the Silicon Wafer.The particle that newly is applied as penetrability (for example: proton) be used to produce the local defect that penetrates Silicon Wafer, with the framework that blocks as separation mixed signal (digital signal and simulation letter), and the inductance of realizing the high Q value of tool (quality factor (quality factors)) on single-chip (sees also US Patent6,046,109 to Liao, Chungpin et al. (2000)).

Recently in the research, the particle beams even be regarded as fine engraving tool is as silicon nitride (Si ₃N ₄) material on dig out the hole of nanoscale (or molecular size), be beneficial to various in the future electronics, chemistry and biological relevant application aims.In addition, also be that an important ion beam is used with particle beams bombardment nuclear species with preparation radio chemistry product and the medical thing of nuclear, they generally are used for detecting and treatment.

Yet above-mentioned various application all are subjected to common restriction physically, and promptly owing to the reciprocation of the particle beams and material, under given condition, the range of the particle beams in object is almost fixed, and in fact can be calculated quite accurately.Therefore if will deeper penetrate object (or in the medical thing of nuclear is produced, producing more nuclear reaction), the required cost of paying is the energy that increases charged particle beam, that is increases the equipment investment of particle accelerator or ion implanter may.With regard to practical engineering application, highly charged particle energy means low current and low processing procedure production capacity, for example is the complementary matal-oxide semiconductor of control (Complementary Metal-Oxide Semiconductor; CMOS) bolt of assembly connection effect need be made fall back well and buried layer, just need to use energy and extremely count MeV up to 400KeV, but electric current only has the energetic ion cloth of 0.005mA to 0.05mA to plant machine.More all the more so for the nuclear medicine thing production of high energy particle bundle (15 to 30MeV cyclotrons) for needs.

Yet, above-mentioned phenomenon be because now accelerator and cloth plant machine all waste too many energy excite or free object in lattice electron, but not be used for desirable nuclear scattering (processing) or nuclear reaction (production).For example, when the charged particle that is higher than several MeV energy by the neutral atom group time, its more than half energy is with the Coulomb force reciprocation between the electronics of loss in charged particle and atom.Even the average loss of energy of this charged particle is no more than several eV in the contact each time, but add these frequent electron excitations of stack up and cause topmost energy loss in this charged particle per unit path with free, opposite, though is greatly with the kinetic energy of being lost during atomic nucleus contact far beyond the former at each charged particle, but probability takes place and but belongs to extreme rareness in it, its effect probability roughly is directly proportional with the ratio of atomic nucleus to the sectional area of atom, that is, 10 ^-24Cm ²/ 10 ^-16Cm ²=10 ^-8So,, nucleus collision there is no considerable contribution on the energy loss of the particle beams in object.Therefore, when particle passes a certain object, as silicon, the energy of one vast scale all is consumed in exciting with free of lattice electron, but not is used for nuclear scattering.

Summary of the invention

So, main purpose of the present invention is to utilize one to add the auxiliary radiation bundle, this auxiliary radiation bundle is close to and is parallel to the particle beams, conduction electron makes charged particle beam become the dynamic quasi-neutral particle beams in the auxiliary radiation Shu Jifa object because this adds, thereby significantly reduce the electron excitation energy loss that the particle beams and object are done the time spent, plant the energy range of machine in various applications in order to expansion accelerator and cloth, and do not need they itself are made an amendment, and allow traditional accelerator and cloth plant function by this on various interesting materials, to reach degree of depth doping impurity, degree of depth sputter is analyzed, the high efficiency defective produces, and deep ion bundle engraving, a large amount of and economic purposes such as nuclear medicine thing production.In addition, add man-hour carrying out the IC semi-conductor industry particle beams, can significantly reduce the particle beams in object the nuclear reaction degradation effects that may cause.

The present invention is applied on the semiconductor applications, an effective method can be provided, reach the purpose that between the analog to digital on the same semiconductor chip, simulation-simulation or digital-digital integrated circuit (IC), forms effective electrical isolated district, and be applied to system single chip (system-on-a-chip according to this; SOC) processing procedure; And more economical method can be provided, the quality factor of the high IC inductance of (semiconductor substrates) last generation at the semiconductor-based end and the purpose of transmission line (transmission-lines) are achieved.

The present invention is applied to radioisotope (radioisotopes), the medical thing production field of nuclear, then can make people finish the manufacturing of various radioactivity nuclear species, compound, medicine with accelerator low-yield, high electric current.

Description of drawings

Fig. 1 is the schematic diagram that sets up of the present invention.

Fig. 2 is the energy loss figure of arsenic, phosphorus, boron in the known silicon base.

Fig. 3 is the electronstoppingpower curve of known particle in electron gas.

Fig. 4 is the electronstoppingpower curve of particle of the present invention in electron gas.

Fig. 5 is that proton beam of the present invention penetrates range figure in silicon.

Fig. 6 is that known high energy electron beam is injected energy and change in depth relation in the silicon.

Fig. 7 is the known distribution on angle of scattering through the X-of Kang Pudun scattering ray or gamma-radiation.

Fig. 8 is energy-depth map of injecting silicon with boron of the present invention.

Detailed Description Of The Invention

In electricity slurry or plasma physics and nuclear fusion field, the known fact is: when charged particle passes an electron gas or electricity slurry (seeing Fig. 1), those have electronics far below the speed of the particle beams 20 few absolutely with particle generation reciprocation; Those electronics with speed suitable with the particle beams 20 then can be made reciprocation and electronic shield is become quasi-neutrality with set mode and particle. This fact has been used as the mode that nuclear merges the heating of electricity slurry, such as: current drives and neutral beam are injected etc.

Stop in the formula at known effective particle, for example by Lindhard, Brandt, the model that Kitagawa and Ziegler etc. does (seeing Ziegler J.et al., 1985), object 10 are the electricity slurries that are regarded as having the joint conduction feature. Accurate especially in the particle beams 20 energy ranges of 10MeV/amu at 200KeV/amu by the above-mentioned Lindhard theoretical formula of deriving, above-mentioned amu represents atomic mass unit (atomic mass unit; Amu), atomic mass roughly is equal to the atomic weight (for example, the amu of proton is about 1) of particle.

See also shown in Figure 1, it is the schematic diagram that sets up of the present invention, as shown in the figure: undesired electronic stopping energy loss when acting on the zone of action 11 of object 10 by the compacting particle beams 20, method of the present invention be utilize add and with the zone of action 11 of auxiliary radiation bundle 30 on object 10 of the particle beams 20 almost parallels, come the conduction electron in the acceleration zone 11, or be used for producing new high speed conduction electron and cover original conduction electron.

About the importance of the relative velocity of conduction electron in the charged particle beam 20 and the zone of action 11 and quantitative explanation will propose behind stopping power (stopping power) formula below inquiring into.

For above-mentioned purpose, its quantitative image can by following stopping power (dE/dx) expression obtains:

$-\left(\frac{\mathrm{dE}}{\mathrm{dx}}\right)=n[S_n\left(E\right)+S_e\left(E\right)]---(J/m)$

Wherein E is the kinetic energy of particle, and n is the atomicity density of object 10, S _nAnd S _eRespectively be nuclear and the electron scattering energy loss in the unit travel distance.Method of the present invention is significantly to reduce electron scattering energy loss (S in the formula (1) with the effective electriferous state that reduces the incident charged particle _e).For example, when the energy of particle is when so-called " Bethe-Bloch district " (making an appointment with the high-energy of several MeV), be applied to aforesaid circuit on silicon when isolated, its corresponding known inelastic scattering electronstoppingpower formula is for (to see also: MeyerhofW.E., Elements of Nuclear Physics, p.77, McGraw-Hill Book Co., 1967 but use metric unit):

${(-\frac{\mathrm{dE}}{\mathrm{dx}})}_e\&ap;\frac{e^4{z}^2\mathrm{<figure-callout\; id="4"\; label="nZ"\; filenames="A0310483200241.png"\; state="\{\{state\}\}">nZ</figure-callout>}}{4\mathrm{\&pi;}{\mathrm{\&epsiv;}}_0^2{m}_0{v}^2}\&CenterDot;\ln \frac{2m_0{v}^2}{I_{\mathrm{ave}}}---(J/m)$

Wherein, the electric charge of ze=high energy charged particle

m ₀=electron mass

The speed of v=high energy particle

Number of electrons density in the nZ=target

I _AveThe electronics of atom on average excites and ionization energy in=the target

The z that supposes (2) formula the right can reduce with a multiplier f (f is less than 1), that is because the incoming particle electron screening that auxiliary radiation bundle (30) causes, then the electronic stopping energy loss of relevant penetrating particle will with f square ratio reduce.Please note, the high-speed situation that we are interested at this, that is 2z/137 β＜1 (during β=v/c), classic physical image, comprise its impact parameter (impact parameter) and with the classical mechanics mode lead used various arguments during formula (2), all no longer valid.Have the derivation of using quantum mechanics, set fluctuation class and explanation only and be only correct (seeing also: Evans R.D., TheAtomic Nucleus, p.584-586, McGraw-Hill, 1955).

Verified by known document, in meeting most all electronic stoppings cross section (cross sections) derivation of equation of experimental data, common important consideration parameter is that electronics and the relative velocity between the electronics in the object zone of action 11 on the incident charged particle (sees also: Ziegler J.et al., The Stopping and Range of Ions in Solids, Chap.3 and Appendix I, Pergamon Press, (1985)).We find, when the average speed of electronics on the incident charged particle is lower than the speed of conduction electron in the solid, can approx the electronics on the aforementioned particles are considered as being stripped from fully.Conduction electron in these zones of action (11) is assumed to be free electron gas (electricity slurry), its Fermi's speed Be that the number of electrons density N of object 10 decides during by low temperature, wherein be respectively Planck's constant divided by 2 π and static electron mass with m.For quantized electron gas, Fermi's speed is the speed of the electronics that occupies high energy rank, the just speed of conduction electron.The effective charge ratio that experiment has confirmed incoming particle for (see also: Ziegler J.et al., ibid):

$q=1-\exp (-\frac{0.92v_r}{v_0{z_1}^{2/3}})$

Wherein: z ₁Atomic number for incoming particle.

$v_r\&equiv;<|\stackrel{\&RightArrow;}{v}-{\stackrel{\&RightArrow;}{v}}_e|>$ Be incoming particle (speed

) and conduction electron (speed ) between relative velocity.

v ₀For ripple ear speed (Bohr velocity), be about 2.2 * 10 ⁸Cm/s, (or represent be about 25keV/mu with energy).

Clearly, work as v _r＞＞v ₀The time, q=1; And work as v _r＞＞v ₀The time, q will significantly diminish, and just make projectile be quasi-neutrality.Traditionally, have only when particle's velocity approaches Fermi's speed of electronics in the target, i.e. 1＜(v _e/ v _F)＜5 o'clock, the minimizing situation of electronic stopping just may take place.See also particle shown in Figure 3 electronstoppingpower curve in electron gas, show when its particle rapidity equals Fermi's speed of electron gas among the figure, breakover point will appear in the electronstoppingpower curve of particle, promptly as the arrow indication locate (see also: Ziegler J.et al., The Stopping and Range of Ions in Solids, p.71, Pergamon Press, (1985)).In fact, although be the other end in power spectrum, this is also just why as particle energy (for example, 10-800keV, that is be that present VLSI impurity cloth is planted the scope that processing procedure is used) very little the time, the electronstoppingpower formula becomes following form and (sees also: Wolf S.and Tauber N., Silicon Processing, Vol.1, p.288, LatticePress, 1986):

${(-\frac{\mathrm{dE}}{\mathrm{dx}})}_e={\mathrm{KE}}^{0.5}---(J/m)$

Reason.What wherein, proportionality constant K was only slight changes (see shown in Figure 2, the energy loss figure of arsenic in the known silicon base (As), phosphorus (P), boron (B)) with the atomic number of projectile particle and object (10) and mass number.In other words, in low-yield scope, the electron screening effect is very remarkable, so that projectile is quasi-neutrality, and then causes the above-mentioned result who concerns projectile and object 10 kinds that almost do not have.

And at a high-octane end, see also shown in Figure 3, the electronstoppingpower curve of particle in electron gas, electronstoppingpower is to the relation curve of number of electrons density in the object 10 among this figure, in fact also clearly described this point (seeing also: Ziegler J.et al., Chap.3 (1985)).That is the electron screening of high energy particle has caused the breakover point (being that electronic stopping reduces) of electronstoppingpower similarly, just, because v _F∝ N ^1/3, needed particle rapidity is more than desirable height, and, even if particle rapidity can raise so far, because conduction electron is to carry out random motion in the object 10, so that after the direction through average all electronics, v _rStill greater than projectile particle rapidity v rather than near-zero (seeing also: Ziegler J.et al., the notional result among the ibid), make q → 0 phenomenon only can in low-yield scope, realize after all traditionally.

So in order no longer to be subject to the number of electrons density in the solid, just break away from Fermi's speed in fact, speed and direction that the present invention is to use the electron beam that adds or auxiliary radiation to control conduction electron, even do not stint with cover original object 10 conduction electrons, make that the speed of new conduction electron is that we are desired, wherein this electron beam that adds or its direction of auxiliary radiation are close to the direction that is parallel to incoming particle bundle 20.V so then _r=| v-v _e| will be less than v and v ₀, cause q less than 1, or approach zero.Hereat, the present invention in fact expanded to the neutralization of projectile particle charging (such as formula (3) description) the scope of the paramount particle energy of validity.Because present v _eMaximum be not Fermi's speed but the speed that decides by the condition of adding (auxiliary radiation bundle (30)).In fact, even replace original conduction electron fully by the rapid movement electronics that adds and also can reach above-mentioned purpose.Its result is learnt that by formula (2) in broader energy range, the electronic stopping energy loss that the particle beams 20 is suffered can significantly reduce in object 10.See also shown in Figure 4, be the electronstoppingpower curve of particle of the present invention in electron gas, the figure shows through after the Theoretical Calculation, expection electronstoppingpower curve break can drift be added the conduction electron speed that condition is controlled to being equal to, and no longer relevant with electron density (or Fermi's speed).In other words, the electronstoppingpower curve is no longer transferred in unpractical high target electron density place or is walked flat (being shown in shown in Figure 4), but at our the desired low target electron density place that sees.

The used auxiliary radiation bundle 30 that adds can be taked as high energy electron, X-ray (X-ray) or gamma-radiation (form such as γ-ray) among the present invention.In addition, though use cover curtain protection object 10, making object 10 not be subjected to above-mentioned auxiliary radiation damage is an effective practice, yet along with needed result, can select to use the cover curtain or not use the cover curtain.Advantage of the present invention be utilize easily obtain, cheap and radiation source easily assembling comes expansion technique complexity, price are expensive again more existing accelerator and cloth is planted machine range of application.For example, utilization does not consume electric power by the gamma-radiation that radioactive decay disengaged.These saved particle energys can guide incoming particle, enter the darker target degree of depth, or generation more defects, also can expect to make people be used more low-energy incoming particle, and and then can significantly reduce many benefits of radiation decay change effect because of such energy-efficient.For example, we know that the proton beam that needs the 4MeV energy approximately just can make a proton and a silicon atom stone grafting touch and produce nuclear reaction, so for being lower than the proton of this energy, it may cause nuclear reaction hardly in silicon target.

In low-energy scope, atomic nucleus stops effect rather considerable, and to heavier particle, and its electronic stopping (being described by formula (4)) begin to become crosspoint of stoping greater than nuclear is position in higher-energy.For example, to boron ( ¹¹B), the electronic stopping energy loss is its main energy loss mechanism, in silicon by higher-energy down to～10keV all is always; And to phosphorus ( ³¹P) and arsenic ( ⁷⁵As), it is main energy loss mechanism that nuclear stops, and will respectively just become main energy loss mechanism (seeing figure two) to 130keV and 700keV electronic stopping in silicon (Si) always.Method of the present invention can cause further incoming particle electric charge quasi-neutralityization (quasi-neutralization).Therefore, for example, the boron cloth of tool 100-200keV is planted machine can reach increase easily after the utilization method of the present invention range that penetrates.Cloth as for phosphorus and arsenic is planted, and such getting well is in when energy is higher than about 1MeV also can be expected.

Relevant most preferred embodiment of the present invention now is described as follows with regard to conjunction with figs.:

Embodiment one, the proton beam that uses electron beam to assist are applied to the degree of depth of silicon (Si) or germanium silicide (SiGe) is penetrated.

This embodiment is that utilization adds auxiliary radiation bundle 30 enhancing proton beams on the semiconductor-based end, as silicon (Si), germanium silicide (SiGe) or nearest carbon germanium silicide (SiGeC), to reach the high-quality IC inductance and the practical purpose of the electrical obstruct between hybrid circuit.Because when impedance (substrate resistivity) value of substrate increases (to about 10 preceding being caused significantly by the proton beam bombardment of IC encapsulation ⁵-10 ⁶Ω-cm) afterwards, it no longer is one provides the path that disturbs signal.And according to the processing procedure of the inventive method, it caused moment leakage current and the attenuating of A.C. losses (AC losses) quality factor q that also improves the IC inductance greatly (see also: Liao et al.ibid).Wherein, the auxiliary radiation bundle 30 that adds is forms of mining height energy electron beam.

For the silicon IC chip of the preceding thickness wear down of encapsulation to about 330 μ m, calculating according to SRIM software, want the proton beam of about 6.5MeV just can penetrate such thickness, 6.5MeV proton beam penetrates the energy-change in depth curve (reducing factor f with respect to different projectile electric charges) of the thick silicon of 330 μ m, can obtain by realistic Numerical Integral Formulas (2), and be presented in shown in Figure 5, be that proton beam of the present invention penetrates range figure in silicon, come as can be seen from Figure, in the silicon target material in the range of 330 μ m, proton beam has only used about 0.5MeV to stop in desirable nuclear, and the 6MeV that has wasted other is on electronic stopping, this shows with traditional naked proton beam bombardment (f=1) and compare that (as: so f=0.8 is f even only a little proton charge covers ²=0.64) the projectile energy-efficient that, it caused is also considerable.

In this example, must the have an appointment kinetic energy of 0.5MeV of required auxiliary high-energy electron beam, just can penetrate the above-mentioned silicon that we are interested in, see also shown in Figure 6, known high energy electron beam is injected the energy in the silicon and the variation relation of the degree of depth, these electron beams are used to light the free cascade (ionization cascade) of electronics in the target, and this effect can be covered and be replaced the conduction electron of both having deposited in fact, to reach the purpose of the electric charge that covers the incident proton beam.Because when low temperature, conduction electron number of densities N may hang down only about 10 ⁵Cm ^-3(approaching proton beam density), and the speed of the speed of a 0.5MeV electronics average proton in this example, thus the electric current of required auxiliary electron bundle be chosen as less than or equate with the proton beam electric current, help the proton beam quasi-neutralityization.

Getable best situation is in this example from the above, needed proton beam energy only just can reach desired purpose for 0.5MeV (but not 6.5MeV), this means that the significantly letter of the particle beams 20 energy economizes the unlatching of the chance of using with the big electric current of the various particles beams (20), aspect auxiliary radiation, the electron beam of required energy range is relatively inexpensive and is easy to obtain.

If target maintained in certain temperature range to be needed, then the about 0.5MV of the beam power that is applied * 50 μ A=25W do not constitute difficulty to the cooling technology of both having deposited.Perhaps, based on special needs, also can arrange through the IC chip or the wafer of suitably shielding with rotation sweep mode batch processed.

Embodiment two, (proton beam that X/ γ-ray) is auxiliary is applied to the degree of depth of silicon (Si) or germanium silicide (SiGe) is penetrated to use the X/ gamma-radiation.

In this embodiment, used auxiliary radiation is to be X-ray (X-ray) or the gamma-radiation (form of γ-ray).Identical with the first embodiment method, this example is that utilization adds auxiliary radiation bundle (30) enhancing proton beam on the same semiconductor-based end, as silicon (Si), germanium silicide (SiGe) or nearest carbon germanium silicide (SiGeC), to reach the practical purpose of the obstruct between high-quality IC inductance and hybrid circuit.

Known relevant X-ray and the attenuation coefficient (attenuationcoefficients) of gamma-radiation in silicon wafer are as shown in the table:

Energy	Wavelength	Attenuation coefficient (cm -1)	Attenuation length	Photoelectron maximum scattering angle *
					1keV	12.4	3743.8	2.7μm	180°
10keV	1.24	78.5	127.4μm	180°
					100keV	0.12	0.40	2.5cm	160°
500keV	0.024	0.25	4.0cm	90°
					1.25MeV	0.001	0.13	7.6cm	50°

^*Incident direction with respect to the X/ gamma-radiation

By last table, observe from the angle of energy, there is no tangible boundary between X-ray and gamma-radiation.

Generally speaking, the X-ray is roughly across the energy range of 1-50keV, γ-ray then includes the above power spectrum of 50keV, and the X-ray is to produce (as with high-energy electron bombardment tungsten target) in artificial mode, and gamma-radiation is then roughly from the radioactive decay of inconstant element.

In order to reach our purpose, for example select the X-ray (or gamma-radiation) of 30keV energy, can penetrate our applied silicon thickness, main related physical reaction mechanism is photoelectric effect and Kang Pudun scattering between the X-of this energy range ray (or gamma-radiation) and lattice electron.

In the photoelectric absorption process, X-ray (or gamma-radiation) photon of incident and the atom effect of absorbing material, and complete obiteration own, what replace it is by high-energy light electronics that bond course penetrates in the atom.Above-mentioned reciprocation is the bound electron that acts in the atom of object 10, but not betide free electron, and photon for the enough energy of tool, most possible photoelectron source is by the inner electron of very powerful constraint, as the K electron in the silicon atom, when these rooms at internal layer are inserted by outer-shell electron again, just can penetrate new photon, cause photoelectronic cascade and produce (cascade generation).

The interaction process of Kang Pudun scattering, betide between X-ray (or gamma-radiation) photon and the free electron in the target of incident, promptly when by the binding energy of photon to the power transfer of object 10 electronics much larger than relevant object 10 electronics, it is quite important that this process becomes.The photon of incident refraction takes place and with former incident direction shape at an angle, and photon sends the some of its energy to electronics at this moment, this electronics promptly is called recoil electron (recoil electron) subsequently.Because various scattering angles are all possible, the big I of the energy that is transmitted is by the zero more than half energy to incident X-ray photon, and the recoil electron that produces, if energy is enough big, can follows and cause electron excitation follow-up in object 10 and free again.

The part of relevant Kang Pudun scattering (Compton scattering), X-ray (or γ-ray) the average absorption cross section in target is:

$\mathrm{\&sigma;}_a^e\&ap;\frac{8\mathrm{\&pi;}}{3}{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="A0310483200261.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2(a-4.2a^2+14.7a^3+\&CenterDot;\&CenterDot;\&CenterDot;){\mathrm{<figure-callout\; id="2"\; label="cm"\; filenames="A0310483200241.png"\; state="\{\{state\}\}">cm</figure-callout>}}^2/\mathrm{electron},$ When $a=\frac{{\mathrm{hv}}_0}{m_0{c}^2}<<1---\left(5\right)$

Wherein: r ₀It is classic electron radius

Hv ₀It is incident photon energy

m ₀It is static electron mass

C is the light velocity, so m ₀c ²≈ 0.5MeV

All scattering and absorption coefficient then are:

$\mathrm{\&sigma;}_e=\mathrm{\&sigma;}_a^e+\mathrm{\&sigma;}_s^e\&ap;\frac{8\mathrm{\&pi;}}{3}{\mathrm{<figure-callout\; id="0"\; label="r"\; filenames="A0310483200261.png"\; state="\{\{state\}\}">r</figure-callout>}}_0^2(1-2a+5.2a^2-13.3a^3+\&CenterDot;\&CenterDot;\&CenterDot;){\mathrm{<figure-callout\; id="2"\; label="cm"\; filenames="A0310483200241.png"\; state="\{\{state\}\}">cm</figure-callout>}}^2/\mathrm{electron},$

When $a=\frac{{\mathrm{hv}}_0}{m_0{c}^2}<<1---\left(6\right)$ The average energy of Kang Pudun recoil electron is:

T _Ave=hv ₀-hv ', or $\frac{T_{\mathrm{ave}}}{{\mathrm{hv}}_0}=1-\frac{{\mathrm{hv}}^{\&prime;}}{{\mathrm{hv}}_0}=1-\frac{\mathrm{\&sigma;}_s^e}{\mathrm{\&sigma;}_e}=\frac{\mathrm{\&sigma;}_a^e}{\mathrm{\&sigma;}_e}\&ap;\frac{a-4.2a^2}{1-2a}\&ap;a---\left(7\right)$

If in following formula with 30keV substitution hv ₀, we promptly get T _Ave≈ 2keV approaches the binding energy of K electron in the silicon.

Therefore, on the path of X-ray (or gamma-radiation), average recoil electron has enough kinetic energy and causes follow-up lattice electron free, and and then facilitates generation to be roughly parallel to the purpose of the high speed conduction electron of proton beam.It is to be described by the Klein-Nishida formula that relevant X-ray (or gamma-radiation) scattering angle distributes, see also shown in Figure 7, distribution on angle of scattering (sees also: Meyerhof W.E. through the X-of Kang Pudun scattering ray or gamma-radiation, Elements of Nuclear Physics, p.96, McGraw-Hill, 1967), for the X-ray (or gamma-radiation) of 30keV, the backscattering of photon (backscattering) is rather remarkable as can be known.Yet, in a lot of occasions that we use because needed X-ray (or gamma-radiation) when tanning by the sun compole short, be unlikely the open defect that causes desire not to see to target and the IC assembly on it.

Estimate the total energy absorption of photoelectric effect and Compton-effect for summary, then cause half of about 2keV/ (600eV/electron) with the inner electron that each ionizing event was produced, that is, an about forward scatter electronics calculates, and the speed of these electronics and proton be almost parallel quite and with it.Know further that more needed conduction electron number of densities is about 10 under the low temperature of using at present ⁵～10 ⁶Cm ^-3Then beating at diameter is that needed X-ray (or gamma-radiation) power is about 3W to 30W on 2 centimeters objects 10, such energy load does not constitute difficulty to the cooling technology of both having deposited, perhaps, if really not so in some specific situation, then X-ray (or gamma-radiation) can the mode with pulsed operate in about 1～3 second of proton irradiation.In addition, in the rotation sweep mode, batch processing also is feasible mode through the IC chip or the wafer of suitably shielding.

Embodiment three, utilize the X-ray auxiliary, the deep boron cloth that is applied on Si and the SiGe is planted.

This embodiment is applied to do the useful case that deep boron cloth is planted on Si and SiGe, its practice is with numerical method the formula (4) that includes different neutral charge multiplication factors " f " to be made integration, the result then is shown in Fig. 8 (see also shown in Figure 8, be energy-depth map of injecting silicon with boron of the present invention).Obvious, boron electric charge screening effect in various degree (different f values), economization electronic stopping energy loss that can be in various degree.For example, when f=0.5, the auxiliary 100keV boron ion beam of X-ray can reach the range of the pure boron ion beam of traditional 200keV, and compared to 0.34 μ m range of traditional boron ion beam of identical energy, (promptly stop the decision energy loss by nuclear fully best, f=0) in silicon, can the have an appointment range of 3.4 μ m of situation, new boron ion beam of the present invention.

Embodiment four, utilize gamma-radiation auxiliary, be applied to the radioisotope production of fluoro-18.

Isotope fluoro-18 can be produced by the nuclear species of high energy proton (hydrogen ion) bundle bombardment oxygen-18.This fluoro-18 is the FDG medicament through chemical synthesis usually again, as the usefulness of positron radiation CT (computer tomography) (PET).The present invention is the proton beam (being the quasi-neutrality hydrogen particle beams) that utilizes γ-ray auxiliary, can be with lower energy (5-10MeV) output and traditional with same fluoro-18 output of high energy proton bundle (20-30MeV).

What be worth mentioning among the present invention is that in Fig. 1, this object (10) can be the material beyond the silicon, for example silicon (Si), germanium (Ge), germanium silicide (SiGe), GaAs (GaAs), indium phosphide (InP), plastic cement etc.Perhaps, the particle beams (20) can be separated into several particle speed of the same race or not particle of the same race, as proton, deuterium, helium, argon, nitrogen, carbon, oxygen, silicon, arsenic, phosphorus, boron etc. or any molecule.These employed particles are gone through in the whole route that quickens and slow down at it, can be charged or uncharged.Or transition in both.

Symbol description

Object (10) zone of action (11) particle beams (20)

Auxiliary radiation bundle (30)

Claims (10)

1. one kind forms dynamic quasi-neutral bundle mode and reduces the method that the various particles beams and object are made the electron excitation energy loss of time spent, it is characterized in that:

Include an object (10);

One puts on the particle beams (20) of the zone of action (11) on this object (10);

One adds auxiliary radiation bundle (30) in this zone of action (11), and this spoke helps the intimate particle beams (20) that is parallel to of radiation beam.

2. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that, this object (10) is to be solid, comprises: silicon (Si), germanium (Ge), germanium silicide (SiGe), GaAs (GaAs), indium phosphide (InP), gallium nitride (GaN), carborundum (SiC), InGaN (InGaN), Im-Ga-Al nitride (AlInGaN), silicon nitride (Si ₃N ₄), silicon dioxide (SiO ₂), silex glass, lithium niobate (LiNbO ₃), lithium tantalate (LiTaO ₃), carbon (C), polymer, nuclear medicine thing material, radioisotope flag compound and examine medical thing.

3. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that this object (10) is the biological structure for flexible material, inorganic and organic compound.

4. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that, this particle beams (20) is to comprise: hydrogen, deuterium, helium, argon, nitrogen, carbon, oxygen, silicon, arsenic, phosphorus, boron atomic element, and vague generalization compound and molecule.

5. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that its particle of this particle beams (20) is in the different band electricity condition, comprise-5 ,-4 ,-3,-2 ,-1,0, + 1, + 2 ,+3 ,+4, + 5, and it has the energy between 250keV to 500MeV.

6. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to a kind of of claim 1 to form dynamic quasi-neutral bundle mode, it is characterized in that this particle beams (20) can be the mixing of variety classes particle.

7. form dynamic quasi-neutral bundle mode according to claim 1 and reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent, it is characterized in that, the form of this auxiliary radiation bundle (30) comprises electron beam, positron bundle or electromagnetic field, and this electromagnetic field comprises microwave, millimeter wave, infrared ray, X-ray and gamma rays.

8. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that this auxiliary radiation bundle (30) has the frequency spectrum that comprises different wave length.

9. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that this object (10) is the temperature range that maintains between-270 to+100 degree Celsius.

10. reduce the method that the various particles beams and object are made the electron excitation energy loss of time spent according to the formation dynamic quasi-neutral bundle mode of claim 1, it is characterized in that, this particle beams (20) be current range between 10 μ A to 10mA, the proton beam of energy range between 0.5 to 30MeV, and this auxiliary radiation bundle (30) be magnitude of current scope between 10 μ A to 10A, the electron beam of energy range between 0.5 to 30MeV, and this object (10) is the thick silicon base of 100 μ m to 2mm.

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