1327225 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種電性檢消丨，A a 衔州/口具及其應用之封裝基板 電性檢測方法，尤指-種適用於多層封裝基板之線路檢測 及較低製作與維護成本之電性檢測治具及其制之封裝基 板電性檢測方法。 【先前技術】 無論是終端電子產品或令上游零組件，出貨之品質為 H)客戶極為重視之一環，亦關係著製造商本身之商譽，因此 產品檢測作業係廠商於資本投資時不可或缺的一部分。一 般而言，電子產品必須做到電性檢測、外觀及表面瑕疲檢 驗；其中，電性檢測工作係判斷產品電性品質之良窳，因 此係目前業界相當重視之議題。 [5 ^封裝基板之電性檢測原理，一般係包括一次測試與二 次測試，其中一次測試係檢測封裝基板置球側表面之焊球 塾間有無短路（short circuit)或斷路（〇pencircuit)的缺陷，而 二次測試係、檢測封裝基板置球側表面之焊球塾（_ pad)與 置晶側表面之焊指（finger)間有無短路或斷路的缺陷。 〇 圖1係利用電性檢測治具進行一次測試之示意圖，其 中，治具之獨立探針13與封裝基板之焊球墊21電性接觸， 並利用測試程式判斷其焊球墊21間之線路是否有短路或斷 路之瑕疵（如圖中之短路23將由測試程式判斷出）。其中由 於一次測試僅能檢測焊球墊間之線路狀況，而無法檢測焊 1327225 球墊21與焊指22間之線路24是否有瑕疵，因此尚必須進行 二次測試。 圖2係習知利用電性檢測治具進行二次測試之示音 圖，其中，治具之探針13與封裝基板之烊球墊2〗電性接= 5並輸入訊號，並用一導電橡膠14(Sh〇rtlng rubberyf所有的 焊指串連在一起，使整個線路形成電性導通，或者利用電 容感應原理，14係為一電容感應板，與該些焊指對應且相 靠近而不電性接觸（如圖3之電性檢測治具，於稍後介紹）， 其訊號經由放大器3傳至中央處理器4，利用測試程式判斷 10封裝基板之球墊21與焊指22間之線路24是否有短路或斷路 之瑕疵（如圖中之斷路241將由測試程式判斷出）。 圖3係一習知電性檢測治具之立體圖。該檢測治具1係 利用電谷感應原理，包括：一第一檢測板1 1，其一表面具有 一電容感應區111及一非電容感應區112 ;以及一第二檢測 15板12，其一表面具有複數探針121。如圖4所示，該電容檢 測治具僅能檢測焊球墊與焊指間之線路，而無法檢測焊= 22間之線路25狀況（如圖中之斷路251);再者，如圖5所示， 在多層封裝基板2中，同一線路26於垂直方向往往因内層有 線路重疊，使該電性檢測治具之電容感應區lu所對應之A 20區電容量變異過大，致不易得到正確的檢測結果，因此對 多層封裝基板而言’其檢測涵蓋率（c〇verRate)偏低。 由於上述該習知電性檢測治具應用於多層封裴基板 時’易有盲點發生’故有另一習知電性檢測治具，係利用 電流導通原理進行電性檢測，以確保產品出貨品質。如圖6 =習：：一電性檢測治具之立體圖，係包括一第一檢 L表面具有複數第-探針511 ;以及·_第二檢測 電性二=具有複數第二探針521。其卜由於該習知 ^具5係以複數第一探針5n及相對應之複數第二 木用電流導通原理進行電性檢測，得以避免前一習 生檢測治具所遇檢測盲點之問題，其檢測涵蓋率可至 而右：:!而，該習知電性檢測治具5卻因需具有多數探針， 有氣作與維護成本過高之缺點。 10 發|種兼具有高涵蓋率效益，且製作與維護 低之電性檢測治具係本發明之重要目標。 【發明内容】 一本&明之主要目的係在提供一種電性檢測治具，尤指 15 ==於多層封袭基板檢測’兼具高涵蓋率及較低製作 /、'准濩成本之電性檢測治具。 :、達成上述目❾’本發明提供一種電性檢測治具，包 戌=一檢測板’其一表面具有一電容感應區及一非電 =應區’該電容感應區具有複數第一開孔；以及複數第 其係配置於該些第一開孔内且與該些第一開孔内 之韭2接觸。其中’該電容感應區可對應於一封裝基板 谷檢測盲點之焊指，並藉由電容值之量測以判斷線 =否有缺陷’而該些第一探針則可與電容檢測盲點之焊 :電性接觸，並藉由電流值之量測以判斷檢測之線路是否 有缺陷。 20 1327225 ^發明之電性檢測治具中，該非電容感應區可具有 開孔’且;f复包括一第二探針，其係配置於該第 至少一第 開孔内且與該第二開孔内壁不電性接觸。盆中，节些第 二探針可與該封裝基板之連接墊電性接觸，並藉由量_ 接塾間或連接塾與焊指間之電流值以判斷連接塾間或 墊與辉指間之線路是否有缺陷；或藉由該些第二探針盘連 接塾電性導通，並於對應該封裝基板谭指之該電容感應區 產生感應電容，以電容值判斷該封裝基板之連接 間之線路是否有缺陷。 〃坪夺曰 15 此外，本發明之電性檢測治具復包括一第二檢 其一表面具有複數第三探針，而該些第三探針可與該封裝 基板之焊球塾電性接觸，並藉由量測焊球墊間、焊球㈣ 連接塾間或焊料與焊指m值以·其間之線路Γ 否有缺陷；或藉由該些第三探針與焊球塾電性導通2 對應該封裝基板谭指之該電容感應區產生感應電容，以雷 容值判斷該封裝基板之焊料與焊指間之線路是 陷D ’缺 本發明之另一目的係在提供一種封裝基板之電 方法’包括以下步驟：提供—電性檢測治具，其包括— 第-檢測板：其一表面具有一電容感應區及一非電容感： 區’該電容感應區具有複數第_開孔；複數第一探二 配置於該些第一開孔内且與該些第一開孔内壁性垃 觸；以及-第二檢測板，其—表面具有複數第三 供-封裝基板，係具有-第—表面及相對之__第二表$， 20 =第—表面具有複數第1指及複數第二輝指，又該第 與夺封# 使°玄第—檢測板之該些第-探針 興。亥封裝基板第-表面之該歧第 第二檢測板之該些第三探針:二二=接觸，且使該 谭球塾電性接觸；以及提供一.列f —表面之該些 —檢測板之該些第-探料電性連接該第 〜第一核測板之該些第三探 物;：其Γ:試儀器提供電流，並藉由量測電流值以測 ;:;板'線路是否有缺陷。此外，該封裝基板之該 10 更可具有至少—連接塾，且該第一檢測板之該非 電谷感應區復具有至少—第二探針，係供與該連接塾電性 接觸，並電性連接至該測試儀器。 15 上述之電性檢測方法更可包括：使該第-檢測板之該 電容感應區與該封裝基板第一表面之該些第二焊指、該些 第-焊指對應且相靠近而不電性接觸，並使該第二檢測板 之該些第三探針與該封裝基板第二表面之該些焊球墊電性 接觸；以及提供-測試儀器，其係電性連接該第一檢測板 之該電容感應區與該第二檢測板之該些第三探針，其中， 該測試儀器提供電壓差，並藉此於該封裝基板之第1焊指 與該第-檢測板之電容感應區間量測其感應電容值，以^ 20 測該封裝基板之該些焊球塾與該些第二焊指間之線路是否 有缺陷。 上述之電性檢測方法中，該電容值量測與該電流值量 測係分別量測，又該些第一焊指為該電容感應區之檢測盲 點處，其可藉由與該些第一探針電性接觸，以量測電流值 $ 9 1327225 之方式進打線路檢測，避免因電容檢測盲點所造成 品流至客戶端之問題，因而提高電性檢測之涵蓋、： 產品出貨品質。 千確保 據此，本發明所提供之電性檢測治具係利用結人 習知電性檢測治具之電流值量測及電容值量測原^ 效降低電性檢測治具之製作與維護成本，同時 檢測之高涵蓋率效益。 电Γ1327225 IX. Description of the invention: [Technical field of the invention] The present invention relates to an electrical detection method, a a state, a mouthpiece, and a package substrate electrical detection method thereof, and particularly, a multilayer package. The electrical detection tool for the circuit detection of the substrate and the lower manufacturing and maintenance cost and the electrical detection method of the package substrate. [Prior Art] Whether it is terminal electronic products or upstream components, the quality of shipment is H) The customer attaches great importance to the ring, and also relates to the goodwill of the manufacturer itself. Therefore, the product inspection operation is not available for the capital investment. Part of the missing. In general, electronic products must be tested for electrical detection, appearance, and surface fatigue. Among them, electrical testing is the best way to judge the electrical quality of products, so it is a topic that the industry is paying attention to. [5^The principle of electrical detection of package substrates generally includes one test and two tests. One test is to detect whether there is a short circuit or a break circuit between the solder balls on the ball-side surface of the package substrate. Defects, and the secondary test system detects defects such as short circuit or open circuit between the solder ball 塾 (_ pad) on the ball-side side surface of the package substrate and the finger on the crystallized side surface. FIG. 1 is a schematic diagram of a test using an electrical test fixture, wherein the independent probe 13 of the fixture is in electrical contact with the solder ball pad 21 of the package substrate, and the test program is used to determine the line between the solder ball pads 21 Whether there is a short circuit or an open circuit (the short circuit 23 in the figure will be judged by the test program). Since one test can only detect the condition of the line between the solder ball pads, it is impossible to detect whether there is flaw in the line 24 between the ball pad 21 and the welding finger 22, so a secondary test must be performed. 2 is a schematic diagram of a conventional test using an electrical test fixture, wherein the probe 13 of the fixture and the ball pad 2 of the package substrate are electrically connected to each other and input a signal, and a conductive rubber is used. 14 (Sh〇rtlng rubberyf all the welding fingers are connected together to make the whole line electrically conductive, or using the principle of capacitive sensing, the 14 series is a capacitive sensing board, corresponding to the welding fingers and close to each other Contact (as shown in the electrical detection fixture of FIG. 3, which will be described later), the signal is transmitted to the central processing unit 4 via the amplifier 3, and the test program is used to determine whether the line 24 between the ball pad 21 and the welding finger 22 of the 10 package substrate is There is a short circuit or an open circuit (the circuit breaker 241 in the figure will be judged by the test program). Figure 3 is a perspective view of a conventional electrical detection fixture. The detection fixture 1 utilizes the electric valley sensing principle, including: A detecting board 1 1 has a capacitive sensing area 111 and a non-capacitive sensing area 112 on one surface thereof, and a second detecting 15 board 12 having a plurality of probes 121 on one surface thereof. As shown in FIG. 4, the capacitance detecting is performed. The fixture can only detect between the solder ball pad and the welding finger The road is unable to detect the condition of the line 25 of the welding = 22 (the open circuit 251 in the figure); further, as shown in FIG. 5, in the multilayer package substrate 2, the same line 26 is often overlapped by the inner layer in the vertical direction. Therefore, the capacitance of the A 20 region corresponding to the capacitance sensing region lu of the electrical detecting fixture is too large, so that it is difficult to obtain a correct detection result, so the detection coverage rate (c〇verRate) of the multilayer package substrate is Since the above-mentioned conventional electrical detection jig is applied to a multi-layer sealed substrate, it is easy to have a blind spot, so there is another conventional electrical detection jig, which is electrically detected by the current conduction principle to ensure the product. Shipment quality. Figure 6 = Xi:: A stereogram of an electrical test fixture, including a first inspection L surface with a plurality of probes 511; and · _ second detection electrical two = with a complex second The probe 521. Because the conventional device 5 is electrically detected by the plurality of first probes 5n and the corresponding plurality of second woods using the current conduction principle, the detection of the previous test fixture can be avoided. Blind spot problem, its detection coverage rate can be And right::! However, the conventional electrical detection fixture 5 has the disadvantage of being too expensive due to the need for a plurality of probes, and has a high cost of coverage and production. Maintaining a low electrical detection fixture is an important object of the present invention. [Summary of the Invention] The main purpose of a & Ming is to provide an electrical detection fixture, especially 15 == detection on a multi-layered substrate. High coverage rate and lower production /, 'immediate cost of electrical detection fixtures. : : To achieve the above objectives 'The present invention provides an electrical detection fixture, including = a detection board' has a capacitor on one surface The sensing area and a non-electrical area are: the capacitive sensing area has a plurality of first openings; and the plurality of first portions are disposed in the first openings and are in contact with the first two of the first openings. Wherein the capacitance sensing area can correspond to a soldering finger of a package substrate valley detecting a blind spot, and the capacitance value is measured to determine whether the line is defective or not, and the first probes can be soldered to the capacitance detecting blind spot. : Electrical contact, and the current value is measured to determine whether the detected line is defective. 20 1327225 ^ In the electrical detection fixture of the invention, the non-capacitive sensing region may have an opening '; and the f includes a second probe disposed in the first at least one opening and the second opening The inner wall of the hole is not electrically contacted. In the basin, the second probes can be electrically contacted with the connection pads of the package substrate, and the current value between the contacts or the contacts and the fingers can be used to determine the connection between the pads or between the pads and the fingers. Whether the circuit is defective; or the second probe disk is connected to the electrical conduction, and the sensing capacitance is generated in the capacitive sensing region corresponding to the package substrate, and the connection between the package substrates is determined by the capacitance value. Is the line defective? In addition, the electrical detection fixture of the present invention includes a second inspection surface having a plurality of third probes, and the third probes can be in electrical contact with the solder balls of the package substrate And by measuring the solder ball pad, the solder ball (4) connecting the turns or the solder and the finger m value, and the circuit between them is defective; or by the third probe and the solder ball 2 The sensing capacitance is generated in the capacitive sensing area of the package substrate, and the line between the solder and the soldering fingers of the package substrate is judged by the lightning value. The other object of the present invention is to provide a package substrate. The electrical method includes the following steps: providing an electrical detection fixture, comprising: a first detecting board: a surface thereof has a capacitive sensing area and a non-capacitive sensing area: the area 'the capacitive sensing area has a plurality of first opening holes; a plurality of first probes disposed in the first openings and in contact with the inner walls of the first openings; and a second detection plate having a plurality of third supply-package substrates having a surface - surface and relative __ second table $, 20 = first surface has complex 1 refers to the first and second plurality of luminance means, should the first seal and capture the first # Xuan ° - plates of the plurality of detection - hing probe. The third probes of the second detecting plate of the first surface of the package substrate: two or two = contact, and the tan ball is electrically contacted; and a column f - the surface is provided - detecting The first probes of the board are electrically connected to the third probes of the first to first nuclear test panels; and the other: the test instrument supplies current and measures the current value to measure; Is the line defective? In addition, the 10 of the package substrate may have at least a connection port, and the non-electric valley sensing region of the first detection plate has at least a second probe for electrically contacting the connection and electrically Connect to the test instrument. The above-mentioned electrical detection method may further include: causing the capacitive sensing region of the first detecting board to correspond to and close to the second welding fingers of the first surface of the package substrate; Contacting the third probes of the second detecting board with the solder ball pads of the second surface of the package substrate; and providing a test instrument electrically connected to the first detecting board The capacitance sensing area and the third probes of the second detecting board, wherein the testing instrument provides a voltage difference, and thereby the capacitive sensing interval of the first welding finger and the first detecting board of the package substrate The value of the sensing capacitor is measured to determine whether the wiring between the solder balls and the second soldering fingers of the package substrate are defective. In the above electrical detection method, the capacitance value measurement and the current value measurement system are separately measured, and the first welding fingers are at the detection blind spot of the capacitance sensing area, which can be performed by the first The probe is electrically contacted, and the line detection is performed by measuring the current value of $ 9 1327225 to avoid the problem that the product is flowed to the client due to the detection of the blind spot by the capacitance, thereby improving the coverage of the electrical detection, and the quality of the product shipment. According to the above, the electrical detection fixture provided by the invention utilizes the current value measurement and the capacitance value measurement of the conventional electrical detection fixture to reduce the manufacturing and maintenance cost of the electrical detection fixture. At the same time, the detection of high coverage rate benefits. Electric pick
10 15 【實施方式】 以下係藉由特定的具體實施例說明本發明之審扩 式’熟習此技藝之人士可由本說明書所揭示之内容輕易地 了解本發明之其他優點與功效。本發明亦可藉由其他不同 的具體實施例加以施行或應用，本說明書中的各項細節亦 可基於不㈣點與制，在不㈣本發明之㈣ 種修飾與變更。 • 請參考圖7，為本發明一較佳實施例之電性檢測治 具立體圖。該電性檢測治具6係包括：一第—檢測㈣，皇 :表面具有一電容感應區611及-非電容感應區612，該電 容感應區611具有複數第一開孔613，以及複數第一探針 20 614’係配置於該些第一開孔613内且與該些第—開孔 壁不電性接觸。 又上述之電性檢測治具6巾，該非電容感應區612具有 至少一第二開孔615，且復包括-第二探針616 ’係配置於 該第二開孔615内且與該第二開孔615内壁不電性接觸。 £ 10 1327225 上述之電性檢測治具6,復包括一第二檢測板62，其— 表面具有複數第三探針621。 、 本發明復提供-封裝基板之電性檢測方法，請參考圖 8，係藉由應用上述之電性檢測治具，以進行一封裝基板7 電性檢驗之剖視圖。其中，該封裝基板7具有一第一、表 1面73 ，相對，-第二表面7b，且該第一表面乃具有複數第一‘ 私71、複數第二焊指72(於剖視圖中係與第一焊指？！位置重 疊）、及複數連接墊74,又該第二表面7咕有複數焊球塾π 15 首先，使該第一檢測板61之該些第一探針6丨4與該封裝 基板7第一表面7a之該些為電容檢測盲點之第一焊指？！電 性接觸，該些第二探針616與該封裝基板7第一表面乃之該 些連接塾74電性接觸，而該第一檢測板61之該電容感應區 611則與該封裝基板7第一表面乃之該些第二焊指”、該些 第一焊指71對應且相靠近而不電性接觸，且使該第二檢測 f 62之該些第三探針621與該封裝基板7第二表面几之該些 焊球塾73電性接觸接著，提供__測試儀器8，其係、電性連 接該第一檢測板61之該些第一探針614、該些第二探針616 與該第二檢測板62之該些第三探針621，並藉由量測該些焊 球塾73間、該些焊球墊73與該些第一帛指叩、該些連接 墊74間及該些連接墊74與該些第一焊指”間之電流值以 檢測其間之線路是否有缺陷；隨後，再藉由該第二檢測板 62之該些第三探針621及該第一檢測板61之該電容感應區 611 ’係分別與該測試儀器8電性連接，該測試儀器8提供電 壓差，並藉此於該封裝基板7之第二焊指72與該第一檢測板 20 1327225 ，以檢測該封裝基[Embodiment] The following is a description of the present invention by way of specific embodiments. Those skilled in the art can readily appreciate the other advantages and advantages of the present invention from the disclosure herein. The present invention may be embodied or applied by other different embodiments, and the details of the present specification may be based on the (four) point system and the (four) modification and alteration of the invention. Please refer to FIG. 7, which is a perspective view of an electrical detection device according to a preferred embodiment of the present invention. The electrical detection fixture 6 includes: a first detection (four), the emperor: the surface has a capacitive sensing region 611 and a non-capacitive sensing region 612, the capacitive sensing region 611 has a plurality of first openings 613, and a plurality of first The probes 20 614 ′ are disposed in the first openings 613 and are not in electrical contact with the first opening walls. In addition, the non-capacitive sensing region 612 has at least one second opening 615, and the second detecting probe 616 is disposed in the second opening 615 and the second The inner wall of the opening 615 is not in electrical contact. £10 1327225 The electrical detection fixture 6 described above further includes a second detection plate 62 having a plurality of third probes 621 on its surface. The present invention provides a method for electrically detecting a package substrate. Referring to FIG. 8, a cross-sectional view of electrical inspection of a package substrate 7 is performed by applying the above-described electrical test fixture. The package substrate 7 has a first, a first surface 73, an opposite second surface 7b, and the first surface has a plurality of first 'private 71' and a plurality of second solder fingers 72 (in the cross-sectional view) The first welding finger is overlapped with the first position, and the plurality of connecting pads 74, and the second surface 7 has a plurality of solder balls 塾 π 15 . First, the first probes 6 丨 4 of the first detecting plate 61 are The first surface 7a of the package substrate 7 is the first finger of the capacitance detecting blind spot? ! The first probe 616 is in electrical contact with the first surface of the package substrate 7 , and the capacitive sensing region 611 of the first detecting board 61 is opposite to the package substrate 7 . a surface of the second soldering fingers, the first soldering fingers 71 corresponding to each other and not in electrical contact, and the third probes 621 of the second detecting f 62 and the package substrate 7 Electrically contacting the solder balls 73 of the second surface, and then providing a test instrument 8 electrically connected to the first probes 614 of the first detecting board 61 and the second probes 616 and the third probes 621 of the second detecting board 62, and by measuring between the solder balls 73, the solder ball pads 73 and the first fingers, the connecting pads 74 And a current value between the connection pads 74 and the first solder fingers to detect whether the circuit between them is defective; and then, the third probes 621 and the second detection board 62 The capacitive sensing region 611 ' of the detecting board 61 is electrically connected to the testing device 8 respectively, and the testing device 8 provides a voltage difference, and is thereby applied to the package substrate 7 a second soldering finger 72 and the first detecting board 20 1327225 to detect the package base
61之電容感應區61 1間量測其感應電容值 板7之該些第 陷。The capacitance sensing area 61 of 61 measures the capacitance of the sensing capacitor value board 7.
綜上所 第一探針， 免因電容檢測盲點所造成缺陷產品流至客戶端之問題，進 而確保產品出貨品質；又該電性檢測治具復利用電容感應 區，以檢測非電容檢測盲點之線路，可以減少第一探針數 量，以有效降低治具之製作與維護成本。因此，本發明兼 10具達到電性檢測高涵蓋率與有效降低成本之效益。 上述實施例僅係為了方便說明而舉例而已，本發明所 主張之權利範圍自應以申請專利範圍所述為準，而非僅限 於上述實施例。 15 【圖式簡單說明】 圖1係進行電性檢測之一次測試之示意圖。 圖2係進行電性檢測之二次測試之示意圖。 圖3係習知一電性檢測治具之立體圖。 圖4係焊指間線路連接狀況示意圖。 20 圖5係多層封裝基板内層線路之示意圖。 圖6係習知另一電性檢測治具之立體圖》 圖7係本發明之電性檢測治具之立體圖。 圖8係本發明之電性檢測治具應用於封裝基板之電性檢剛 方法之剖面示意圖。 12 1327225 【主要元件符號說明】In summary, the first probe avoids the problem that the defective product caused by the capacitance detection blind spot flows to the client, thereby ensuring the quality of the product shipment; and the electrical detection fixture reuses the capacitive sensing area to detect the non-capacitance detection blind spot. The circuit can reduce the number of first probes to effectively reduce the manufacturing and maintenance costs of the fixture. Therefore, the present invention has the advantages of achieving high coverage of electrical detection and effectively reducing costs. The above-described embodiments are merely examples for the convenience of the description, and the scope of the claims is intended to be limited by the scope of the claims. 15 [Simple description of the diagram] Figure 1 is a schematic diagram of one test for electrical detection. Figure 2 is a schematic diagram of a secondary test for electrical detection. 3 is a perspective view of a conventional electrical detection fixture. Figure 4 is a schematic diagram of the connection state between the welding fingers. 20 Figure 5 is a schematic diagram of the inner layer of a multi-layer package substrate. Figure 6 is a perspective view of another electrical detection fixture of the prior art. Figure 7 is a perspective view of the electrical detection fixture of the present invention. Fig. 8 is a schematic cross-sectional view showing an electrical test method for applying an electrical test fixture of the present invention to a package substrate. 12 1327225 [Main component symbol description]
1,5,6 電性檢測治具 11,51,61 第一檢測板 111,611 電容感應區 112,612 非電容感應區 12, 52, 62 第二檢測板 121, 13 探針 14 導電橡膠 2,7 封裝基板 21,73 焊球墊 22 焊指 23 短路 24, 25, 26 線路 241,251 斷路 3 放大器 4 中央處理器 511,614 第一探針 521,616 第二探針 613 第一開礼 615 第二開孔 621 第三探針 7a 第一表面 7b 第二表面 71 第一焊指 72 第二焊指 74 連接墊 8 測試儀器 131,5,6 Electrical detection fixture 11, 51, 61 First detection board 111, 611 Capacitive sensing area 112, 612 Non-capacitive sensing area 12, 52, 62 Second detection board 121, 13 Probe 14 Conductive rubber 2, 7 package substrate 21,73 solder ball pad 22 welding finger 23 short circuit 24, 25, 26 line 241, 251 open circuit 3 amplifier 4 central processing unit 511, 614 first probe 521, 616 second probe 613 first opening 615 second opening 621 third probe 7a first surface 7b second surface 71 first welding finger 72 second welding finger 74 connection pad 8 test instrument 13