527618 A7 _______B7___ 五、發明說明（/ ) 相關申請案 以下的美國專利申請案在此倂入作爲參考，如同其已 完整地提出，：申請案案號：________，領域________， 名稱’’用於防止離子植入器束線內的中子輻射之機構”。 發明之領域 本發明係關於離子植入系統，且特別是用於抑制在這 種系統的束線內產生之中子輻射的機構，尤其是高能量離 子植入系統。 發明背景 離子植入已變成工業界在量產積體電路時，對半導體 摻雜雜質上所青睐之技術。高能量離子植入器用於深植入 於基板之內。舉例而言，此深植入被用來製造退化井。527618 A7 _______B7___ V. Description of Invention (/) The following U.S. patent applications related to the application are hereby incorporated by reference as if they had been filed in their entirety: Application number: ________, field ________, name `` for Mechanism for preventing neutron radiation in the beam line of an ion implanter. "FIELD OF THE INVENTION The present invention relates to an ion implantation system, and in particular, a mechanism for suppressing the generation of neutron radiation in the beam line of such a system. Especially high-energy ion implantation system. BACKGROUND OF THE INVENTION Ion implantation has become a favored technology for doped semiconductor impurities in industrial circuits when mass-producing integrated circuits. High-energy ion implanters are used for deep implantation in substrates. Inside, for example, this deep implant is used to make degenerate wells.
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Eaton GSD/HE及GSD/VHE離子、植入器爲此高能量植入器 之例。這些植入器可提供能量高達5 MeV(百萬電子伏特) 之離子束。本發明之所有人，Eaton公司，所擁有之美國 專利第4,667，111號，說明了此高能量離子植入器。 離子植入器操作在非常高的電壓等級。典型上，束中 的離子由植入器中的電極及其他元件作加速與減速，以維 持在不同的電壓等級。例如，正離子由離子源中被抽取， .通過質量解析磁鐵，並由具有遞增負電位的電極加速。在 高能量離子植入器中，離子束在通過射頻(RF)線性加速器 (linac)時作加速。離子束藉由通過一連串的加速級（共振器 模組)行經RF線性加速器，其中，加速場是藉由將RF電 壓的頻率與離子束的速度同步而產生。 4 衣紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） ------------裝--------訂--------- (請先閱讀背面之注意事項再填寫本頁) 527618 A7 ______B7 _ 五、發明說明（2 ) 砷(As)與磷(P)是經常被植入半導體中，作爲摻雜媒介 的2種元素。砷與磷典型上被注入至離子源，分別離子化 成爲砷化三氫(AsH3)與磷化氫(PH3)氣體，其中每一者包括 了氫(H)作爲承載氣體。這些在離子化腔體中之氣體的離子 化過程經常會產生小量的重氫一 1種氫的同位素。從離子 源中抽取出的離子束線經常包含了氘核子，它是重氫原子 的核子，每個包含了 1個質子與1個中子。因此，氘核子 爲帶有單位正電荷的次原子粒子。 從離子源抽取的氘核子延著離子束線被傳送至質量解 析磁鐵。具有正確荷質比的可植入離子(例如As+、As++、 P+及P++)通過質量解析磁鐵，同時，具有不正確荷質比的 粒子（例如氖核子）打在質量解析磁鐵的內部側壁上。這些Eaton GSD / HE and GSD / VHE ion implanters are examples of high-energy implanters. These implants can provide ion beams with energy up to 5 MeV (million electron volts). The owner of the present invention, Eaton Corporation, U.S. Patent No. 4,667,111, illustrates this high energy ion implanter. Ion implanters operate at very high voltage levels. Typically, the ions in the beam are accelerated and decelerated by electrodes and other components in the implanter to maintain different voltage levels. For example, positive ions are extracted from the ion source, the magnet is resolved by mass, and accelerated by an electrode with increasing negative potential. In high-energy ion implanters, the ion beam is accelerated as it passes through a radio frequency (RF) linear accelerator (linac). The ion beam travels through an RF linear accelerator through a series of acceleration stages (resonator modules), where the acceleration field is generated by synchronizing the frequency of the RF voltage with the speed of the ion beam. 4 The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ------------ installation -------- order -------- -(Please read the notes on the back before filling out this page) 527618 A7 ______B7 _ V. Description of the Invention (2) Arsenic (As) and phosphorus (P) are two elements that are often implanted in semiconductors as doping media . Arsenic and phosphorus are typically implanted into the ion source and ionized into triarsenide (AsH3) and phosphine (PH3) gases, each of which includes hydrogen (H) as a carrier gas. The ionization of these gases in the ionization chamber often produces a small amount of deuterium, a kind of hydrogen isotope. The ion beam line extracted from the ion source often contains deuteron, which is the nucleus of heavy hydrogen atom, each containing 1 proton and 1 neutron. Therefore, a deuteron is a subatomic particle with a unit positive charge. The deuteron extracted from the ion source is transmitted along the ion beam line to the mass-analysis magnet. Implantable ions (such as As +, As ++, P +, and P ++) with the correct charge-to-mass ratio pass through the mass-resolving magnet, while particles with incorrect charge-to-mass ratio (e.g., neon nuclei) hit the inner sidewall of the mass-resolving magnet. These ones
Γ I 側壁通常襯有打擊板，典型上使角石墨構成，其爲碳(C)的 六角結晶同素異構物。 在所知的碳同位素C-11至C-15之中，C-12及CM3 兩者是穩定的且數量最多。在C-12(或12C)符號中的數字 12代表質子（6)與中子（6)的總和。在地球上所發現的碳同 位素有將近99%爲碳CM2。碳C-13(或13C)在其核子中具 有7個中子與6個質子。在所有的碳原子中，約有1.1%是 .由這種同位素所組成。 用來製作質量解析磁鐵打擊板的石墨通常含有碳CM2 及少量的碳CM3同位素。然而，如果氘核子打在打擊板上 ，可能會發生包括入射氘核子與合成之CM2及C-13石墨 結構中的CM3原子核之核反應。這樣的核反應可能會釋放 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -------------------訂·-------- (請先閱讀背面之注意事項再填寫本頁) 527618 A7 _____Β7___ 五、發明說明（；） 出具有相當能量（高達約5 MeV)之中子。這些來自打擊板 表面的中子輻射是不希望見到的。由氘核子與打擊板中的 碳C-13同位素碰撞所造成的中子輻射在高能量離子植入器 中係特別有問題的，在此，高束能量會增加中子輻射的產 生。 於是，本發明之目的在於提供1種離子植入器束線， 能夠抑制在植入器運作時產生的中子輻射。另一個目的在 於提供連接至質量解析磁鐵內部並與其互通之抑制機構型 式的束線。 發明槪要 一種質量解析磁鐵組件提供在一離子植入器中使用， 包含：⑴用於對一離子源產生之一離子束輸出作質量解析 的磁鐵，該磁鐵提供了該離子束Μ過的一內部區域；以及 (ii)藕合至該磁鐵的一中子抑制腔體。該中子抑制腔體提供 一與該磁鐵內部區域互通之抑制空間，以及部份界定該抑 制空間的中子吸收壁。該中子吸收壁至少部份由一內襯所 覆蓋，當受到通過抑制空間的離子束所承載的氘核子打中 時，能夠釋放中子。最好是，該內襯由石墨構成，且該壁 是由石蠟或聚乙烯構成。該壁包括了吸收石墨內襯釋放出 .的中子或實質上減低其能量等部份。 圖示簡單說明 圖1爲結合了本發明用來在運作時減少中子輻射產生 之高能量離子植入器的示意方塊圖； 圖2爲圖1的方塊圖中之質量解析磁鐵組件的內部平 6 本紙張尺度適用中國國家標準(CNS)A4規格（210 X 297公釐) —·-----------------訂·-------1 (請先閱讀背面之注意事項再填寫本頁) 527618 A7 _ B7_ 五、發明說明（> ) 面圖；以及 圖3爲連接於圖2的質量解析磁鐵組件的打擊板之延 著直線3-3之剖面圖。 元件符號說明 10 離子植入器 12 注入器 14 離子源 15 離子束 16 質量解析磁鐵組件 18 射頻線性加速器 20 共振器模組 22 最終能量磁鐵 23 分解器外殽 ' 24 終端平台 26 旋轉盤 30 可變孔徑 31 第一旗標法拉第 35 第二旗標法拉第 36 孔徑 40 四重透鏡 42 磁鐵 44 外殼 46 打擊板 48 打擊板 7 --.---------*4^ 裝--------訂--------- (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 527618 A7 ______B7 五、發明說明（f ) 49 質量解析磁鐵內部區域 50 分解孔徑 52 中子抑制腔體 54 壁 56 內襯 58 腔體抑制空間 60 壁54未被內襯56覆蓋的部份 發明較佳實施例詳細說明 圖1爲高能量離子植入器10的剖面圖。雖然本發明在 此結合高能量離子植入器之質量解析磁鐵組件加'以說明， 但應了解本發明可結合質量解析磁鐵組件以外之離子植入 器元件，以及除高能量之外的其他型式離子植入器。 r ( 植入器10包含5個部份或子'系統：包括一用來產生一 離子束15的離子源14及一用來對離子束作質量解析的質 量解析磁鐵組件16之注入器12; —包括用來將離子束加 速至較高能量的複數個共振器模組20a-20ii之射頻(RF)線 性加速器(linac)18 ; —用來對加速之離子束執行最終質量 解析的最終能量磁鐵(FEM)22 ; —用於離子束之最終分解 與處理的分解器外殼23 ;以及一終端平台24，其包含一承 ，載晶圓W而使離子束植入之旋轉盤26。也可考慮將旋轉 盤26以單晶圓基座串接離子植入器中來取代。 位於質量解析磁鐵組件16後，在線性加速器18入口 的是用來控制進入線性加速器的束電流量之一可變孔徑3〇 。緊接著孔徑30之後的是用來量測由孔徑3〇輸出並進入 L_._ 8 _ 本紙張尺度適關家標準（CNS)A4規格（21G X 297公爱) "' — — — — —------•裝------- 1訂--------- S (請先閱讀背面之注意事項再填寫本頁) 527618 A7 ____B7____ 五、發明說明（G ) 線性加速器18之束電流的一第一旗標法拉第31。一第二 旗標法拉第35位於分解器外殼23中，用來量測在植入晶 圓W前的離子束電流。 從離子源14抽取出的離子束15在進入質量解析磁鐵 組件16前，通過一界定孔徑36的源頭(也可參照圖2)。通 過質量解析磁鐵組件16的離子束典型上由單一同位素所構 成，並進入RF線性加速器18，其對所通過的離子束提供 額外的能量。RF線性加速器產生隨時間週期性變動的粒子 加速場，其相位可被調整以符合不同原子序的粒子與具有 不同速度的粒子。在RF線性加速器18中的複數個共振器 模組20之每一者用來進一步加速離子，以超越它們從前一 模組所達到的能量。 Γ ( 緊接著每個共振器模組20之後的是一靜電四重透鏡 40。四重透鏡40將所通過離子束再聚焦，以抵消當離子束 通過一特定的共振器模組20時所產生的網狀放射散焦效應 。雖然在圖1中未繪出，四重透鏡40也可被置於緊鄰RF 線性加速器18前後。 圖2較詳細地繪出了質量解析磁鐵組件16。磁鐵組件 16包括由一外殼44所圍住的一磁鐵42。磁鐵42包括由場 .線圏（未繪出)所纏繞的軛(未繪出）。流過線圈的電流控制了 磁場的強度與方向。外殻44內部的一側裝襯有一打擊板 46，且另一側的一部份裝襯有一打擊板48。外殻44內部 的另一側之剩餘部份與根據本發明所建構的一中子抑制腔 體52互通，隨後將更詳盡地說明。 9 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公爱） —.-----------------訂--------- (請先閱讀背面之注意事項再填寫本頁) A7 527618 __B7__ 五、發明說明M ) 質量解析磁鐵組件16用來使離子源14所產生之僅具 有適當荷質比的離子能通往RF線性加速器18。需要有質 量解析磁鐵是因爲離子源Η除了產生適當荷質比的離子外 ，同時也產生比所要植入大或小之荷質比的離子。具有不 適當荷質比的離子不適合植入晶圓。通過質量解析磁鐵內 部區域49的離子束在進入RF線性加速器18之前，於一 分解孔徑50被聚焦。 具有適當荷質比的所需離子延著路徑15b移動，較正 確地說是在路徑15a與15c所界定的離子束路徑包絡內， 因爲束內的類電荷（正）離子的排斥力之故，而發生某種程 度之束發散。標示爲L的路徑描繪了比植入物質之所需荷 質比大的荷質比（即離子的原子質量太低或太輕）之非期望 離子的軌跡路徑。標示爲Η的路'徑描繪了比植入物質之所 需荷質比小的荷質比（即離子的原子質量太高或太重）之非 期望離子的軌跡路徑。 輕離子的軌跡（路徑L)比所需離子的軌跡更受磁場的 影響，且輕離子打在打擊板46上。重離子的軌跡(路徑Η) 不如所需離子的軌跡受磁場的影響，其所受影響較少，且 這些重離子進入中子抑制腔體52。進入抑制腔體52的重 .離子之中，包括從離子源抽取且由延著路徑Η與離子束之 中和部份一齊被承載之氘核子。打擊板46與48部份構成 磁鐵內部區域49的外圍邊界。 藕合至磁鐵外殻44的抑制腔體52包含壁54，其具有 覆蓋其一部份之打擊板內襯56(亦參照圖3)。磁鐵內部區 10 紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公ϋ —.------.—裝--------訂--------- (請先閱讀背面之注意事項再填寫本頁) 527618 A7 _____B7___ 五、發明說明（？） 域49與一腔體抑制空間58互通。部份的打擊板內襯56由 石墨製成，其典型上爲碳c_12與C-13同位素所構成的合 成材質。壁54由中子吸收材質製成，如聚乙烯或石蠟。其 他可能用於製作壁的材質包括：含硼或硼酸聚乙烯、鋰聚 乙烯、硼聚矽氧、中子氧化錫或聚合鑄造(polycast)材質。 延著路徑Η移動的氘核子，通過由打擊板內襯56及 壁54所界定的抑制空間58 ’並打中內襯而間歇性地產生 中子輻射。然而，因氘核子打擊而產生從內襯56輻射或釋 放出的任何中子被包含於抑制腔體52內，主要是藉由壁 54未被內襯56覆蓋的部份60而達成。這些部份60吸收 所產生的中子或實質上減低其能量，使得減小中子輻射的 反效應。 Γ ( 因此，已說明了用來防止離'子植入器束線上之中子輻 射的機構之較佳實施例。然而，根據先前的說明，應明瞭 此處僅以舉例的方式來說明，本發明並未限於在此說明的 特定實施例，且在不背離申請專利範圍及其均等物所界定 的本發明之範疇前提下，可相對於以上說明進行各種重組 、修改與替換。 11 — — — — —------Jf------- 丨訂--------- Sr (請先閱讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐）The Γ I side wall is usually lined with a striking plate, typically made of angular graphite, which is a hexagonal crystalline isomer of carbon (C). Among the known carbon isotopes C-11 to C-15, both C-12 and CM3 are stable and the most abundant. The number 12 in the C-12 (or 12C) symbol represents the sum of protons (6) and neutrons (6). Nearly 99% of the carbon isotopes found on Earth are carbon CM2. Carbon C-13 (or 13C) has 7 neutrons and 6 protons in its nucleus. About 1.1% of all carbon atoms are made up of this isotope. The graphite used to make the mass analysis magnet strike plate usually contains carbon CM2 and a small amount of carbon CM3 isotopes. However, if the deuteron hits the strike plate, a nuclear reaction including the incident deuteron and the CM3 nucleus in the synthesized CM2 and C-13 graphite structures may occur. Such a nuclear reaction may release 5 paper sizes applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ------------------- Order · --- ----- (Please read the notes on the back before filling out this page) 527618 A7 _____ Β7 ___ V. Description of the invention (;) A neutron with considerable energy (up to about 5 MeV). These neutron radiation from the surface of the strike plate are undesirable. Neutron radiation caused by the collision of deuterons with carbon C-13 isotopes in the strike plate is particularly problematic in high-energy ion implanters, where high beam energy will increase the generation of neutron radiation. Therefore, an object of the present invention is to provide an ion implanter beam line, which can suppress neutron radiation generated during the operation of the implanter. Another object is to provide a wire harness of a suppression mechanism type that is connected to and communicates with the inside of the mass analysis magnet. The invention requires a mass analysis magnet assembly to be provided for use in an ion implanter, comprising: a magnet for mass analysis of an ion beam output from an ion source, the magnet providing a An inner region; and (ii) a neutron suppression cavity coupled to the magnet. The neutron suppression cavity provides a suppression space communicating with the inner area of the magnet, and a neutron absorption wall partially defining the suppression space. The neutron absorption wall is at least partially covered by a lining, and can release neutrons when hit by a deuteron carried by an ion beam passing through the suppression space. Preferably, the lining is made of graphite and the wall is made of paraffin or polyethylene. The wall includes absorbing neutrons released by the graphite lining or substantially reducing its energy. Brief Description of the Drawings FIG. 1 is a schematic block diagram of a high-energy ion implanter incorporating the present invention for reducing neutron radiation during operation. FIG. 2 is an internal plan view of a mass analysis magnet assembly in the block diagram of FIG. 1. 6 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) ---------------------- Order ---- 1 ( (Please read the precautions on the back before filling this page) 527618 A7 _ B7_ V. Description of the invention (&); Top view; and Figure 3 is the straight line of the strike plate connected to the mass analysis magnet assembly of Figure 2 3-3 Section view. Description of component symbols 10 Ion implanter 12 Injector 14 Ion source 15 Ion beam 16 Mass analysis magnet assembly 18 Radio frequency linear accelerator 20 Resonator module 22 Final energy magnet 23 External resolver obfuscation 24 End platform 26 Rotating disk 30 Variable Aperture 31 First flag Faraday 35 Second flag Faraday 36 Aperture 40 Quadruple lens 42 Magnet 44 Housing 46 Strike plate 48 Stroke plate 7 --.--------- * 4 ^ Equipment ---- ---- Order --------- (Please read the notes on the back before filling out this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 527618 A7 ______B7 5 Explanation of the invention (f) 49 Mass analysis magnet inner area 50 Decomposition aperture 52 Neutron suppression cavity 54 Wall 56 Lining 58 Cavity suppression space 60 Part of the invention of the invention where the wall 54 is not covered by the liner 56 is explained in detail FIG. 1 is a cross-sectional view of a high-energy ion implanter 10. Although the present invention is described herein in conjunction with the mass analysis magnet assembly of the high energy ion implanter, it should be understood that the present invention can be combined with ion implanter elements other than the mass analysis magnet assembly, and other types other than high energy Ion implanter. r (The implanter 10 includes 5 parts or sub-systems: including an ion source 14 for generating an ion beam 15 and an implanter 12 for mass analysis magnet assembly 16 for mass analysis of the ion beam; -A radio frequency (RF) linear accelerator (linac) 18 including a plurality of resonator modules 20a-20ii for accelerating the ion beam to a higher energy;-a final energy magnet for performing a final mass analysis of the accelerated ion beam (FEM) 22; a resolver housing 23 for the final decomposition and processing of the ion beam; and a terminal platform 24, which includes a rotating disc 26 that carries a wafer W for implanting the ion beam. It may also be considered The rotating disk 26 is replaced by a single wafer base in series with an ion implanter. Behind the mass analysis magnet assembly 16, at the entrance of the linear accelerator 18 is a variable aperture used to control the amount of beam current entering the linear accelerator. 30. Immediately after the aperture 30 is used to measure the output from the aperture 30 and enter L _._ 8 _ This paper size conforms to the home standard (CNS) A4 specification (21G X 297 public love) " '— — — — —------ • Install ------- 1 Order --------- S (Please read first Please fill in this page again if you need to pay attention to it) 527618 A7 ____B7____ 5. Description of the Invention (G) A first flag Faraday 31 of the beam current of the linear accelerator 18. A second flag Faraday 35 is located in the resolver housing 23 and used to Measure the ion beam current before implanting the wafer W. The ion beam 15 extracted from the ion source 14 passes through a source defining the aperture 36 before entering the mass analysis magnet assembly 16 (see also FIG. 2). The ion beam of the analytical magnet assembly 16 is typically composed of a single isotope and enters the RF linear accelerator 18, which provides additional energy to the passing ion beam. The RF linear accelerator generates a particle acceleration field that periodically changes with time, and its phase Can be adjusted to match particles with different atomic order and particles with different velocities. Each of the plurality of resonator modules 20 in the RF linear accelerator 18 is used to further accelerate ions beyond what they reached from the previous module Γ (Immediately after each resonator module 20 is an electrostatic quadruple lens 40. The quadruple lens 40 refocuses the passed ion beam to offset the ion beam. The net-like radiation defocusing effect produced when a beam passes through a specific resonator module 20. Although not shown in FIG. 1, the quadruple lens 40 can also be placed immediately before and after the RF linear accelerator 18. FIG. 2 is more detailed A mass analysis magnet assembly 16 is depicted on the ground. The magnet assembly 16 includes a magnet 42 surrounded by a housing 44. The magnet 42 includes a yoke (not shown) wound by a field. Line coil (not shown). The current through the coil controls the strength and direction of the magnetic field. One side of the inside of the housing 44 is lined with a striking plate 46, and a part of the other side is lined with a striking plate 48. The remaining portion on the other side inside the housing 44 communicates with a neutron suppression cavity 52 constructed in accordance with the present invention, which will be described in more detail later. 9 This paper size applies to China National Standard (CNS) A4 specification (210 X 297 public love) —.----------------- Order --------- ( Please read the notes on the back before filling this page) A7 527618 __B7__ V. Description of the invention M) Mass analysis magnet assembly 16 is used to make the ions generated by the ion source 14 with only the appropriate charge-to-mass ratio to the RF linear accelerator 18 . The need for a mass-resolving magnet is because the ion source, in addition to producing ions with an appropriate charge-to-mass ratio, also produces ions that have a larger or smaller charge-to-mass ratio than the implant. Ions with an inappropriate charge-to-mass ratio are not suitable for implantation on a wafer. The ion beam passing through the inner region 49 of the mass resolving magnet is focused at a resolution aperture 50 before entering the RF linear accelerator 18. The required ions with the appropriate charge-to-mass ratio move along path 15b, more precisely within the ion beam path envelope defined by paths 15a and 15c, because of the repulsive force of the charge-like (positive) ions in the beam, And some sort of beam divergence occurs. The path labeled L depicts the path of an undesired ion with a charge-to-mass ratio that is greater than the required charge-to-mass ratio of the implanted substance (ie, the ion's atomic mass is too low or too light). The path labeled Η represents the path of undesired ions that have a charge-to-mass ratio that is less than the required charge-to-mass ratio of the implanted material (ie, the ionic atomic mass is too high or too heavy). The trajectory of light ions (path L) is more affected by the magnetic field than the trajectory of the desired ions, and the light ions hit the striking plate 46. The trajectory of heavy ions (path Η) is less affected by the magnetic field than the trajectory of the desired ions, which is less affected, and these heavy ions enter the neutron suppression cavity 52. The heavy ions entering the suppression cavity 52 include deuterons which are extracted from the ion source and carried by the path Η and the neutral part of the ion beam. The striking plates 46 and 48 constitute the peripheral boundary of the inner area 49 of the magnet. The suppression cavity 52 coupled to the magnet housing 44 includes a wall 54 having a striking plate lining 56 covering a portion thereof (see also Fig. 3). The paper size of the inner area of the magnet is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 cm). ------------.-- installation -------- order --------- (Please read the precautions on the back before filling this page) 527618 A7 _____B7___ V. Description of the invention (?) The domain 49 communicates with a cavity suppression space 58. Part of the striking plate lining 56 is made of graphite, which is typically It is a synthetic material composed of carbon c_12 and C-13 isotopes. Wall 54 is made of neutron-absorbing materials, such as polyethylene or paraffin. Other materials that may be used to make walls include boron-containing or boric acid polyethylene, lithium polyethylene , Boron polysilicon, neutron tin oxide, or polycast. Deuterons moving along the path Η pass through the suppression space 58 ′ defined by the strike plate lining 56 and wall 54 and hit the lining. Neutron radiation is generated intermittently. However, any neutrons radiated or released from the lining 56 due to deuteron strikes are contained within the suppression cavity 52, mainly by the wall 54 not being covered by the lining 56 Part 60. These parts 60 absorb the neutrons produced or substantially reduce their energy, making Negative effects of neutron radiation. Γ (Thus, a preferred embodiment of a mechanism for preventing neutron radiation from the beamline of the neutron implanter has been described. However, according to the previous description, it should be understood that only the By way of example, the present invention is not limited to the specific embodiments described herein, and various reorganizations and modifications can be made relative to the above description without departing from the scope of the present invention as defined by the scope of the patent application and its equivalents. And replacement. 11 — — — — —------ Jf ------- 丨 Order --------- Sr (Please read the notes on the back before filling this page) This paper Standards apply to China National Standard (CNS) A4 (210 X 297 mm)