201141245 六、發明說明： 【發明所屬之技術領域】 [0001] 本發明有關一種微機電電容式麥克風’尤指一種具剛 性振膜之微機電電容式麥克風。 [先前技術] [0002] 電子產品的發展趨勢一向朝體積輕薄、效率提升的方 向前進，麥克風的演進亦不例外。麥克風用以接收聲音 並將其轉換為電氣訊號，在曰常生活中應用廣泛’例如 裝置於電話、手機、錄音筆等。以電容式麥克風為例， ^ 聲音的變化會以音波型式迫使薄膜結構產生相對應的變 形’薄膜結構的變形會導致電容發生變化’爰此’可藉 感測電容變化而讀出壓差值而獲知聲音訊的變化。 [0003] 相較於傳統駐極電容式麥克風（electret condenser microphone, ECM) ， 微機電 (Micro-E 1 ectro-Mechanical‘.:Sysrteins，MEMS)式麥 克風可利用積體電路的製程技術，將機械元件與電子元 Q 件整合於一半導體材料上，藉此製作出微型的麥克風， 乃漸成微型麥克風的主流。微機電式麥克風除重量輕、 體積小、省電外，尚具備的優點包括其可利用表面黏著 (surface mount)方式生產、能夠忍受較高的回焊溫度 (reflow temperature)、易於與互補式金屬氧化物半 導體（CMOS)製程以及其他音訊電子裝置整合，以及具有 較佳的抗射頻（RF)和電磁干擾（electromagnetic interference， EMI) 的特性。 [0004] 099115379 圖1」顯示一習知微機電電容式麥克風1的構造示意 表單編號A0101 第3頁/共24頁 0992027245-0 201141245 圖，其包含一背極板2(back-plate)、一振膜 3(membrane or diaphragm)以及一間隔件4。其中， 該間隔件4設置於背極板2與振膜3之間，致使振膜3與背 極板2相互絕緣隔離並平行設置，彼此分別形成一平行電 容板結構的上電極與下電極；背極板2對應振膜3處開設 有複數個音孔5(air hole)，該些音孔5貫通背極板2， 並連通開設於一石夕基板6的一背腔7(back chamber)。 [0005] [0006] [0007] 分別對該背極板2與振膜3施加電壓，可使其電性相異 並帶有電荷，形成一電容結構。根據平行電極板的電容 公式：C=eA/d (其中 ε 為介電係數（(11616〇1；1'：1(：〇〇11-stnt)、Α為兩電極板重合面積、d為兩電容板之間距 (gap))，吾人可知兩電容板間的間距變化將改變電容值 。藉此，當一音波作用於振膜3而造成該振膜3振動、形 變時，振膜3與背極板2之間的間距將會改變，使得電容 隨之變化而可轉換成電氣訊號輸出。位於振膜3與背極板 2之間受擾動、壓縮的空氣，則可自該些音孔5釋放至該 背腔7，避免氣壓變動過大而損壞可撓之振膜3和背極板2 結構。 請配合參閱「圖2」，其顯示一微機電電容式麥克風1 的封裝示意圖。該微機電電容式麥克風1設置於一基板8 ，並封裝於一金屬蓋體9形成的容置空間内。其中，微機 電電容式麥克風1的振膜3與背極版2分別電性連接至一轉 換晶片10，俾使背極板2與振膜3之間的電容變化可藉該 轉換晶片10轉換成電氣訊號而輸出。 惟，習用於微機電電容式麥克風的振膜均為一可撓式 099115379 表單編號A0101 第4頁/共24頁 0992027245-0 201141245 振膜’其利用音壓造成振膜形變的特性來獲致與背極板 間的間距改變，藉以改變電容值。然則，以薄膜沉積可 撓式振膜的製程溫度極高，且因材料彼此間的熱膨脹係 數互有差異’如此將使得振膜在製造的過程中累積程度 不一的張應力或壓應力。殘存於振膜的應力會導致振膜 翹曲，形成皺摺而不平整，導致其影響感測的精準度； 更進一步地，麥克風的靈敏度（sensitivity)與振膜的 殘留應力呈現反比關係，因此過高的應力殘留將導致靈 敏度降低。為此’美國專利第US5490220號之「Solid state condenser and…microphone devices」提出 一種無固定邊界的懸浮振膜，利用一懸臂梁來支撐振膜 ，使振膜懸浮藉以釋放溫度效應造成的應力；美國專利 第US5870482號之「Miniature sili:con .condenser microphone」則延伸應用設計出大型平Μ振膜僅固定一 邊的結構。 [0008] 惟，由於可撓式振膜於形變時無法隨時與背極板保持 平行，因此振膜與背極板之間的間距變化估算不易，精 確度較為不足。再者，由於麥克風的靈敏度正比於驅動 電壓，因此，欲提升靈敏度而提高驅動電壓時，習知之 可撓式振膜容易發生崩潰（collapse)效應，貼附於背極 板而導致麥克風失效。 【發明内容】 [0009] 爰上’本發明之目的在於解決上述問題，進而提出一 種精確度、靈敏度高且製造容易之微機電電容式麥克風 099115379 表單編號A0101 第5頁/共24頁 0992027245-0 201141245 [0010] 為了達成前述目的，士 本發明係透過一剛性振膜與一彈 性元件的搭配’俾使剛 社振膜可平行背極板位移。所提 出之微機電電容式麥克 見風包含—基座、一背極板、一彈 性元件以及一剛性振膜. ，其中，該基座開設一背腔；該 为極板與該彈性元件設 於该基座，該背極板並開設有 複數個音孔，且該些音孔造.s 4 —孔連通該背腔；該剛性振膜設置 3彈性元件，鱗行且對應料極板設置。藉此，當 ^作用於該剛性振膜’該剛性振膜可藉彈性元件之 彈性仙”行該背極板之法向量方向位移。 [0011] 本發明之剛性振媒藉彈性元件的彈性作用或形變而位 陡据腔位移時保持與背極板間的平行關係。藉此，剛 如、背極板間的電容變化僅與兩相_距相關， 提升麥克風於感測、接收音量時的靈敏度與準確 ^有關本發明的詳細技術内容及較佳實 式說明如後。 【實施方式】 [0012] 本發明提出一種微機電電容式益± 备式麥克風，其係利用剛性 振私配雜元件，致使剛性振㈣ 板位移。本發明之有關本發明之詳=仃並相對一㈣ 現配合圖式說明如下： 心㈣及技術内容’ [0013] 請參閱「圖3-1」與「圖3 — 2 眘 > ,,丄 」所不，在本發明之一 貫施例中，所提出之微機電電容 91 式麥克風20包含一基座201141245 VI. Description of the Invention: [Technical Field] The present invention relates to a microelectromechanical condenser microphone, particularly a microelectromechanical condenser microphone having a rigid diaphragm. [Prior Art] [0002] The development trend of electronic products has always been moving toward the direction of thinness and efficiency, and the evolution of microphones is no exception. The microphone is used to receive sound and convert it into an electrical signal, which is widely used in everyday life, for example, in telephones, cell phones, voice recorders, and the like. Taking a condenser microphone as an example, ^ the change of sound will force the film structure to produce a corresponding deformation in the form of sound wave. 'The deformation of the film structure will cause the capacitance to change. 'This can be used to sense the change in capacitance and read the pressure difference. Learn about the changes in voice. [0003] Compared to the conventional electret condenser microphone (ECM), the Micro-E1 ectro-Mechanical'.: Sysrteins (MEMS) microphone can utilize the process technology of the integrated circuit to mechanically The component and the electronic component Q are integrated on a semiconductor material, thereby making a miniature microphone, which is gradually becoming the mainstream of the miniature microphone. In addition to light weight, small size, and power saving, MEMS microphones have advantages such as surface mount, high reflow temperature, and easy and complementary metal. Oxide semiconductor (CMOS) processes and other audio electronics integration, as well as better resistance to radio frequency (RF) and electromagnetic interference (EMI). [0004] 099115379 FIG. 1 shows a schematic diagram of a conventional microelectromechanical condenser microphone 1 Form No. A0101 Page 3 of 24 0992027245-0 201141245, which includes a back-plate, a A membrane or diaphragm and a spacer 4. The spacer 4 is disposed between the back plate 2 and the diaphragm 3, so that the diaphragm 3 and the back plate 2 are insulated from each other and arranged in parallel, and respectively form an upper electrode and a lower electrode of a parallel capacitor plate structure; The back plate 2 is provided with a plurality of air holes 5 corresponding to the diaphragm 3, and the sound holes 5 penetrate through the back plate 2 and communicate with a back chamber formed in a stone substrate 6. [0006] [0007] A voltage is applied to the back plate 2 and the diaphragm 3, respectively, so that they are electrically different and have a charge to form a capacitor structure. According to the capacitance formula of the parallel electrode plate: C=eA/d (where ε is the dielectric constant ((11616〇1; 1':1(:〇〇11-stnt), Α is the overlap area of the two electrode plates, d is two The gap between the capacitor plates, we know that the change in the spacing between the two capacitor plates will change the capacitance value. Thereby, when a sound wave acts on the diaphragm 3 to cause the diaphragm 3 to vibrate and deform, the diaphragm 3 and the back The spacing between the plates 2 will change, so that the capacitance changes to be converted into an electrical signal output. The disturbed, compressed air between the diaphragm 3 and the back plate 2 can be from the sound holes 5 Released to the back chamber 7 to avoid excessive pressure fluctuations and damage the structure of the flexible diaphragm 3 and the back plate 2. Please refer to "Fig. 2", which shows a package diagram of a microelectromechanical condenser microphone 1. The condenser microphone 1 is disposed on a substrate 8 and is packaged in an accommodating space formed by a metal cover 9. The diaphragm 3 and the back plate 2 of the MEMS condenser microphone 1 are electrically connected to a conversion chip, respectively. 10, the capacitance change between the back plate 2 and the diaphragm 3 can be converted into the conversion wafer 10 into The gas signal is output. However, the diaphragm used for the MEMS condenser microphone is a flexible type 099115379 Form No. A0101 Page 4 / Total 24 Page 0992027245-0 201141245 Diaphragm 'It uses the sound pressure to cause the diaphragm deformation The characteristic is to change the distance between the back plate and the back plate, so as to change the capacitance value. However, the process temperature of depositing the flexible diaphragm with the film is extremely high, and the thermal expansion coefficients of the materials are different from each other'. Accumulation of varying degrees of tensile stress or compressive stress during manufacturing. Stresses remaining in the diaphragm cause the diaphragm to warp, forming wrinkles and not flattening, causing it to affect the accuracy of sensing; further, the microphone Sensitivity is inversely related to the residual stress of the diaphragm, so excessive stress residuals will lead to a decrease in sensitivity. For this reason, "Solid state condenser and...microphone devices" of US Pat. No. 5,490,220 proposes a non-fixed boundary. Suspended diaphragm, using a cantilever beam to support the diaphragm, so that the diaphragm is suspended to release the stress caused by temperature effects; US patent The "Miniature sili:con .condenser microphone" of US5870482 extends the application to design a structure in which the large flat diaphragm is only fixed on one side. [0008] However, since the flexible diaphragm cannot be parallel to the back plate at any time during deformation Therefore, the variation of the spacing between the diaphragm and the back plate is difficult to estimate, and the accuracy is insufficient. Moreover, since the sensitivity of the microphone is proportional to the driving voltage, the conventional flexible vibration is required to increase the sensitivity and increase the driving voltage. The membrane is prone to collapse effects and is attached to the backplate causing the microphone to fail. SUMMARY OF THE INVENTION [0009] The present invention aims to solve the above problems, and further proposes a micro-electromechanical condenser microphone with high accuracy, high sensitivity and easy manufacturing. 099115379 Form No. A0101 Page 5 / Total 24 Page 0992027245-0 201141245 [0010] In order to achieve the above object, the present invention transmits a rigid diaphragm to the back plate by a combination of a rigid diaphragm and an elastic member. The proposed microelectromechanical capacitive microphone includes a base, a back plate, an elastic component and a rigid diaphragm. The base defines a back cavity; the plate and the elastic component are disposed on The pedestal, the back plate is provided with a plurality of sound holes, and the sound holes are connected to the back cavity; the rigid diaphragm is provided with 3 elastic elements, which are arranged in scale and corresponding to the material plates. Thereby, when the rigid diaphragm is applied to the rigid diaphragm, the rigid diaphragm can be displaced by the elastic element of the elastic member in the direction of the normal vector of the back plate. [0011] The elastic vibration of the rigid vibration medium of the present invention Or the deformation is steep and maintains a parallel relationship with the back plate when the cavity is displaced. Thus, the capacitance change between the rigid and the back plates is only related to the two phases, and the microphone is raised at the sense and receiving volume. Sensitivity and Accuracy The detailed technical content and the preferred embodiment of the present invention are as follows. [Embodiment] [0012] The present invention provides a micro-electromechanical capacitive type-preserving microphone, which utilizes rigid swaying components. The rigid vibration (four) plate displacement is caused. The details of the present invention relating to the present invention are relative to one (four) and the following descriptions are as follows: Heart (4) and technical content ' [0013] Please refer to "Figure 3-1" and "Figure 3 - 2 Caution >, 丄 所 , 在 在 所 所 所 所 所 所 所 所 所 所 所 所 所 所 微 微 微 微 微 微 微 微 微 微 微 微 微 微 微
Zi、—剛性振膜22、一彈性元件μ、 Φ . 3U及一背極板24。其 甲，该背極板24設置於基座21上， 呰把上 背極板24開設有貫通 牙極板24的複數個音孔25 ;該基 099115379 〇 座21相對於背極板24的 表單編號A0101 第6頁/共24頁 0992027245-0 201141245 Ο 位置包含一背腔2 6 ’使得該些音孔2 5得以連通該背腔2 6 。該剛性振膜22固定於該彈性元件23而平行設置於背極 板2 4 —側。因此，該背極板2 4可相對於剛性振膜2 2形成 —固定端，該剛性振膜22則可因彈性元件23的彈性作用 而位移，藉以相對該背極板24形成一活動端。是故，當 —音波作用於剛性振膜2 2而致使剛性振膜2 2相對背極板 24位移時，該剛性振膜22可始終與背極板24保持平行而 平行背極版24法向量方向（即Ζ轴方向）位移。因此，根據 前述平行電極板電容公式，剛性振膜22與背極板24之間 的電容變化便可改寫為AC= ε Α 。其中， 為剛性振膜22受音壓（acoustic pressuire)作用後的位 移量，d為剛性振膜22受音壓作用前與脅極板24的原始間 距。故，相較於習知可撓式振膜上各點與背極板24間的 間距改變量不同，本發明之電容變化與Aχ有關，如此可 提供更大的電容變化量輸出，有效提升麥克風的靈敏度 〇 0 [0014] 請配合參閲「圖3-2」，在上述之一實施例中，該基 座21例如為一矽基板，其上開設圓形之背腔26 ;該彈性 元件23係呈一十字平板交叉樣態，四端固定於該基座21 之背腔26邊緣；該剛性振膜22成一圓形狀，並藉一支推· 件27(anchor)固設於彈性元件23之十字交又處，使剛性 振膜2 2平行彈性元件2 3所構成之平面；該支撐件2 7相對 於彈性元件23之另一端固定於剛性振膜22之圓心，使支 撐件2 7承固剛性振臈22時得以保持該剛性振膜22的物理 平衡，並輔助剛性振膜22進行熱製程時的應力釋放。 099115379 表單編號腦1 帛7頁/共24胃 0992027245-0 201141245 [0015] 該背極板24固定設置於該基座21之背腔26 —侧，開 設複數個音孔25並預留有彈性元件23的設置空間。藉此 ，剛性振膜22可平行設置於背極板24上方，兩者形成平 行電容板結構。請再參閱「圖4」，微機電電容式麥克風 20於運作時，剛性振膜22與背極板24可分別輸入正負電 壓，使其帶有電性相異之電荷而為平行板電容》當剛性 振膜22之一表面承受聲音作用時，來自聲音的壓力可傳 遞至彈性元件23致使其形變，俾使剛性振膜22朝向背極 板24位移（Z轴方向）’而改變兩者間的電容。藉此，經由 外部電路的分析與運算，吾人可將聲音訊號轉變為電氣 訊號而輸出。 [0016] 在上述一實施例中’該微機電電容式麥克風2〇可更包 含至少一絕緣件28(顯示於「圖4」），該絕緣件28設置於 剛性振膜22與背極板24之間，例如設置於剛性振膜22面 對背極板2 4側或該背極板2 4面對剛性振膜2 2側，如「圖4 」顯示位於背極板24的兩絕緣样28，分別設置於背極板 24的·相異兩端。當剛性振膜_2名承受過大的聲壓而導致剛 性振膜22朝背極板24的位移量過大時，該絕緣件28可提 供一緩衝效果並作為剛性振膜22與背極板24之間的雷 ^*3 性 分隔，避免剛性振膜22與背極板24產生電性接觸 [0017] 在上述一實施例中’該剛性振膜22可包含複數個結構 加強部2 9，該些結構加強部2 9例如為加強肋 (r e i n f 〇 r c e d r i b)，可設置於剛性振膜2 2 —側，用以 之 加強剛性振膜22整體之結構強度與並保持剛性振膜22 099115379 表單編號A0101 第8頁/共24頁 0992027245-0 201141245 [0018] [0019] Ο 〇 [0020] 剛性。實務上，達成上述加強部的方式例如利用溝槽回 填技術。 同理’在上述之另一實施例中，該背極板24可包含複 數個結構加強部29，該些結構加強部29例如為加強肋， 可設置於該背極板24背對於剛性振膜22之一側，用以加 強背極板24整體之結構強度與並保持背極板24的剛性》 為方便說明與瞭解’上述將功能不同之結構、元件分 開定義。惟，須說明的是，上述所述及之結構或元件可 互相獨立分離而組裝’或是藉由微機電或半導體製程， 利用蝕刻、微影、自填等讀領域知粦之技術直接製作而 成，例如應用MOSBE之微機電技術平台製程技術來製造本 發明提出之微機電電容式麥克風2〇，其相關之平台技術 可參閱 2005 年發表之「1'116^1〇1(164 81^:^〇6-raicromachining and Bulk Etching Release (MOSBE) Fabrication Plat form on (111) Si for MOEMSj (Journal of Micromechanics and Mi-croengineering, vol. 15, fp; 260-265)，在此不 加贅述。 請再參閱「圖5-1」至「圖5-9」之製造上述微機電 電容式麥克風20—實施例的流程示意圖’該些圖式顯示 沿「圖3-1」中線段Κ-Γ的截面示意，且在不影響本發 明的實施與了解下’省略掉於不同元件中的電性佈線流 程。首先’備製一用於製做基座21的基材，例如為一石夕 基板30，如「圖5-1」所示；接著於該矽基板30定義背極 板24之設置位置，並於其上蝕刻出用於形成前述結構加 099115379 表單編號A0101 第9頁/共24頁 0992027245-0 201141245 強部29的溝槽31，如「圖5-2」；接續地，於該矽基板 上’儿積層多晶梦（p〇ly-silicon)層32，該多晶石夕 層32並回填該些溝槽31，以形成背極板24之結構加強部 29結構，如「圖5-3」。緊接著，於該多晶矽層32的預設 位置钮刻出彈性元件23與音孔25位置，並同時定義出背 極板24之尺寸範圍，如「圖5-4」；該背極板24可藉該些 結構加強部29保持其表面平整與結構剛性，該彈性元件 23則可藉該多晶矽層32的厚度改變或材料選擇，調整自 身之彈性。 [0021] [0022] 然後，於背極板24上形成前述之絕緣件28，該些絕緣 件28之材質例如為氮化石夕（silicon nitride,如 ’如「圖5-5」所示；接著，於背極板24上方形成 一中間層33並同時定義出支撐件27的形成位置，該支揮 件27的形成位置位於彈性元件23上方，如「圖5_6」，該 中間層33例如為二氧化矽（Si〇2);而後，於該中間層33 上再沉積一多晶矽層34，該多晶石夕層34角以定義出剛性 振膜22與支撐件27，如「圖5-f」；接續地，自梦基板 30底側蝕刻出背腔26，如「圖5-8」；最後，蝕刻去除該 中間層33，致使剛性振膜22藉該支撐件27設置於彈性元 件23上，並平行於背極板24，如「圖5-9」。 「圖6」顯示將上述實施例的頻率反應測試結果，係 將前述之微機電電容式麥克風20電性連接一電容讀出晶 片（capacitance readout IC)(MS3110)，並置於一 半音波暗室（semi-anechoic chamber)收取揚聲機 ( loudspeaker)的訊號結果。由圖可知，在聲準位 099115379 表單編號A0101 苐10頁/共24頁 0992027245-0 201141245 [0023] Ο [0024] [0025] [0026] [0027] [0028] 099115379 上述微機電電容式麥克風20Zi, a rigid diaphragm 22, an elastic element μ, Φ. 3U and a back plate 24. The back plate 24 is disposed on the base 21, and the upper back plate 24 is provided with a plurality of sound holes 25 extending through the tooth plate 24; the base 099115379 is formed in the form of the back seat 21 relative to the back plate 24. No. A0101 Page 6 of 24 0992027245-0 201141245 Ο The position includes a back chamber 2 6 ' such that the sound holes 25 are connected to the back chamber 2 6 . The rigid diaphragm 22 is fixed to the elastic member 23 and disposed in parallel on the side of the back plate 24. Therefore, the back plate 24 can form a fixed end with respect to the rigid diaphragm 2 2, and the rigid diaphragm 22 can be displaced by the elastic action of the elastic member 23, thereby forming a movable end with respect to the back plate 24. Therefore, when the acoustic wave acts on the rigid diaphragm 2 2 to cause the rigid diaphragm 22 to be displaced relative to the back plate 24, the rigid diaphragm 22 can always be parallel with the back plate 24 and parallel to the back plate 24 normal vector. The direction (ie, the direction of the x-axis) is displaced. Therefore, according to the aforementioned parallel electrode plate capacitance formula, the change in capacitance between the rigid diaphragm 22 and the back plate 24 can be rewritten as AC = ε Α . Here, it is the amount of displacement of the rigid diaphragm 22 after the sound pressurization, and d is the original distance between the rigid diaphragm 22 and the damper plate 24 before the sound pressure is applied. Therefore, compared with the difference in the distance between the points on the conventional flexible diaphragm and the back plate 24, the capacitance change of the present invention is related to Aχ, which can provide a larger output of capacitance change, effectively raising the microphone. Sensitivity 〇0 [0014] Please refer to FIG. 3-2. In one embodiment, the pedestal 21 is, for example, a cymbal substrate having a circular back cavity 26; the elastic element 23 The cross-plate is in a cross-shaped manner, and the four ends are fixed to the edge of the back cavity 26 of the base 21; the rigid diaphragm 22 is formed into a circular shape, and is fixed to the elastic member 23 by a pusher 27 (anchor) The cross is again disposed such that the rigid diaphragm 2 2 is parallel to the plane formed by the elastic member 23; the other end of the support member 27 is fixed to the center of the rigid diaphragm 22 with respect to the other end of the elastic member 23, so that the support member 27 is fixed. The rigid vibration 22 maintains the physical balance of the rigid diaphragm 22 and assists the rigid diaphragm 22 in stress release during the thermal process. 099115379 Form number brain 1 帛 7 pages / total 24 stomach 0992027245-0 201141245 [0015] The back plate 24 is fixedly disposed on the side of the back cavity 26 of the base 21, and a plurality of sound holes 25 are opened and elastic components are reserved. 23 settings space. Thereby, the rigid diaphragm 22 can be disposed in parallel above the back plate 24, and the two form a parallel capacitor plate structure. Please refer to FIG. 4 again. When the MEMS condenser microphone 20 is in operation, the rigid diaphragm 22 and the back plate 24 can input positive and negative voltages respectively, so that they have electrically different charges and are parallel plate capacitors. When one surface of the rigid diaphragm 22 is subjected to sound, the pressure from the sound can be transmitted to the elastic member 23 to cause it to deform, and the rigid diaphragm 22 is displaced toward the back plate 24 (Z-axis direction) to change between the two. capacitance. Therefore, through the analysis and calculation of the external circuit, we can convert the audio signal into an electrical signal and output it. [0016] In the above embodiment, the microelectromechanical condenser microphone 2 can further include at least one insulating member 28 (shown in FIG. 4), and the insulating member 28 is disposed on the rigid diaphragm 22 and the back plate 24. For example, the rigid diaphragm 22 faces the back plate 24 side or the back plate 24 faces the rigid diaphragm 2 2 side, as shown in FIG. 4 shows the two insulation samples 28 on the back plate 24. They are respectively disposed on the opposite ends of the back plate 24. When the rigid diaphragm 2 is subjected to excessive sound pressure and the displacement of the rigid diaphragm 22 toward the back plate 24 is excessively large, the insulating member 28 can provide a buffering effect and serve as the rigid diaphragm 22 and the back plate 24. In the first embodiment, the rigid diaphragm 22 may include a plurality of structural reinforcing portions 2, 9 of which the rigid diaphragm 22 is electrically connected to the backing plate 24. [0017] In the above embodiment, the rigid diaphragm 22 may include a plurality of structural reinforcing portions 2, 9 The structural reinforcing portion 29 is, for example, a reinforcing rib (reinf 〇rcedrib) which can be disposed on the side of the rigid diaphragm 2 2 for reinforcing the structural strength of the rigid diaphragm 22 as a whole and maintaining the rigid diaphragm 22 099115379 Form No. A0101 8 pages/total 24 pages 0992027245-0 201141245 [0018] [0019] Ο 〇 [0020] Rigidity. In practice, the manner in which the above-described reinforcing portion is achieved is, for example, a groove backfilling technique. Similarly, in another embodiment, the back plate 24 may include a plurality of structural reinforcements 29, such as reinforcing ribs, which may be disposed on the back plate 24 opposite to the rigid diaphragm. One side of the 22 is used to strengthen the structural strength of the back plate 24 as a whole and to maintain the rigidity of the back plate 24. For the convenience of explanation and understanding, the above-mentioned structures and components having different functions are separately defined. However, it should be noted that the structures or components described above may be independently separated and assembled 'either directly by microelectromechanical or semiconductor processes, using techniques known in the fields of etching, lithography, self-filling, etc. For example, the MEMS-based microelectromechanical technology platform process technology is used to fabricate the MEMS condenser microphone proposed by the present invention. The related platform technology can be referred to "1'116^1〇1 (164 81^: published in 2005). ^〇6-raicromachining and Bulk Etching Release (MOSBE) Fabrication Plat form on (111) Si for MOEMSj (Journal of Micromechanics and Mi-croengineering, vol. 15, fp; 260-265), no further details. Please Referring to "Fig. 5-1" to "Fig. 5-9", the flow chart of the above-mentioned microelectromechanical condenser microphone 20 is exemplified. The drawings show the cross section of the line Κ-Γ along the line in Fig. 3-1. And, without affecting the implementation and understanding of the present invention, 'the electrical wiring process is omitted from the different components. First, a substrate for making the susceptor 21 is prepared, for example, a slab substrate 30, such as " Figure 5-1"; followed by The 矽 substrate 30 defines the position at which the back plate 24 is disposed, and the groove 31 for forming the aforementioned structure plus 099115379 Form No. A0101 Page 9/24 pages 0992027245-0 201141245 Strong portion 29 is etched thereon, as shown in the figure 5-2"; successively, on the substrate, a polycrystalline silicon layer 32 is deposited on the substrate, and the polysilicon layer 32 is backfilled to fill the trenches 31 to form the back plate 24 The structure of the structural reinforcing portion 29 is as shown in Fig. 5-3. Next, the position of the elastic member 23 and the sound hole 25 is engraved at the preset position of the polysilicon layer 32, and the size range of the back plate 24 is simultaneously defined. As shown in FIG. 5-4, the back plate 24 can maintain its surface flatness and structural rigidity by the structural reinforcing portions 29, and the elastic member 23 can adjust itself by the thickness change or material selection of the polysilicon layer 32. [0021] [0022] Then, the foregoing insulating member 28 is formed on the back plate 24, and the material of the insulating members 28 is, for example, silicon nitride (eg, as shown in FIG. 5-5). Next, an intermediate layer 33 is formed over the back plate 24 and simultaneously defines the formation of the support member 27. The formation position of the support member 27 is located above the elastic member 23, such as "FIG. 5-6", the intermediate layer 33 is, for example, cerium oxide (Si〇2); then, a polysilicon layer 34 is deposited on the intermediate layer 33. The polycrystalline rock layer 34 defines the rigid diaphragm 22 and the support member 27, as shown in FIG. 5-f. Subsequently, the back cavity 26 is etched from the bottom side of the dream substrate 30, as shown in FIG. 5-8. Finally, the intermediate layer 33 is etched away, so that the rigid diaphragm 22 is disposed on the elastic member 23 by the support member 27 and parallel to the back plate 24, as shown in FIG. 5-9. FIG. 6 shows the result of the frequency response test of the above embodiment, which electrically connects the aforementioned microelectromechanical condenser microphone 20 to a capacitance readout IC (MS3110) and placed in a half-tone darkroom (semi- The anechoic chamber) receives the signal result of the loudspeaker. As can be seen from the figure, in the sound level 099115379 Form No. A0101 苐 10 pages / Total 24 pages 0992027245-0 201141245 [0023] [0024] [0028] [0028] [9928] 099115379 The above-mentioned microelectromechanical condenser microphone 20
而外更兼具體積小、低成本等優點。 商外， 式振膜難以處理應力殘留的問題，剛性振膜㈡不易殘留 -37.97dB/pa。以 克風20 ’除靈敏度 。相較於習知可撓 (sound-level)為94dB下，j 實施例的頻率感測範圍介於J 〇The outside is more specific and small, low cost and so on. Outside the business, the diaphragm is difficult to handle the problem of residual stress, and the rigid diaphragm (2) is not easy to remain -37.97dB/pa. In addition to the sensitivity of the wind 20 ’. The frequency sensing range of the j embodiment is between J 相 compared to the conventional sound-level of 94 dB.
(sensitivity)約為 12. fiSinV 應力’可獲致較佳的感測靈敏度。 屬再特別說明定義的是，本發明中剛性振膜22並非純 然以材料之硬度來定義，而須搭配微機電電容式麥克風1 的電各感測原理而加以定義,。_是:故所謂之剛性振膜2 2 係指振膜不藉自身的形變來改變與背極板24間的電容值 ，而乃須搭配一彈性元件23，並藉彈性元件23的彈性或 形變來改變與背極板24間的電容值，故所述之彈性元件 23也不以上述實施例所顯示者為限。 惟以上所述者’僅為本發明之較佳實施例，非欲侷限 本發明專利之專利保護範圍，故舉凡運用本發明說明書 及圖式内容所為之等效變化與修飾，均同理包含於本發 明之權利保護範圍，合予陳明。 【圖式簡單說明】 本發明的實施方式係結合圖式予以描述： 「圖1」為習知微機電電容式之一麥克風晶片的構造示意 圖； 「圖2」為習知微機電電容式麥克風的封裝示意圖； 「圖3-1」為本發明之微機電電容式麥克風一實施例之立 表單煸號A0101 第.11頁/共24頁 0992027245-0 201141245 體不意圖； [0029] 「圖3-2」為本發明之微機電電容式麥克風一實施例之立 體剖視圖； [0030] 「圖4」為本發明之微機電電容式麥克風一實施例之作動 示意圖； [0031] 「圖5-1」至「圖5-9」為本發明之微機電電容式麥克風 一實施例之流程示意圖；及 [0032] 「圖6」為上述實施例於不同頻率下的輸出結果圖。 【主要元件符號說明】 [0033] 1.......微機電電容式麥克風 [0034] 2.......背極板 [0035] 3.......振膜 [0036] 4.......間隔件 [0037] 5.......音孔 [0038] 6.......矽基板 [0039] 7.......背腔 [0040] 8.......基板 [0041] 9.......金屬蓋體 [0042] 10.......轉換晶片 [0043] 20.......微機電電容式麥克風 [0044] 21.......基座 099115379 表單編號 A0101 第 12 頁/共 24 頁 0992027245-0 201141245 [0045] [0046] [0047] [0048] [0049] [0050] [0051]❹ [0052] [0053] [0054] [0055] [0056] [0057]Ο 22 .......剛性振膜 23 .......彈性元件 24 .......背極板 25 .......音孔 26 .......背腔 27 .......支撐件 28 · · 29 ·. 30 ·. 31 .. 32 ·. 33 ·. 34 ·. 絕緣件 多晶矽層 中間層 多晶石夕層 ••結構加強部 ..二' \ ••砍基板 .:.... …丨《病: ..溝槽(sensitivity) is about 12. fiSinV stress' to achieve better sensing sensitivity. It is specifically stated that the rigid diaphragm 22 of the present invention is not purely defined by the hardness of the material, but must be defined in conjunction with the electrical sensing principles of the microelectromechanical condenser microphone 1. _ is: so the so-called rigid diaphragm 2 2 means that the diaphragm does not change its capacitance value with the back plate 24 by its own deformation, but must be matched with an elastic member 23, and by the elasticity or deformation of the elastic member 23. The capacitance value between the back plate 24 and the back plate 24 is changed, so that the elastic member 23 is not limited to those shown in the above embodiment. However, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the patent protection of the present invention. Therefore, equivalent changes and modifications made by using the specification and drawings of the present invention are equally included in The scope of protection of the present invention is combined with Chen Ming. BRIEF DESCRIPTION OF THE DRAWINGS The embodiments of the present invention are described in conjunction with the drawings: FIG. 1 is a schematic structural view of a conventional microelectromechanical capacitive microphone chip; FIG. 2 is a conventional microelectromechanical condenser microphone. FIG. 3-1 is a schematic diagram of an embodiment of a microelectromechanical condenser microphone according to the present invention. A0101 page 11.11/24 pages 0992027245-0 201141245 body not intended; [0029] "Fig. 3 2 is a perspective cross-sectional view of an embodiment of a microelectromechanical condenser microphone of the present invention; [0030] FIG. 4 is a schematic diagram of an embodiment of a microelectromechanical condenser microphone according to the present invention; [0031] "Fig. 5-1" FIG. 5-9 is a schematic flow chart of an embodiment of a microelectromechanical condenser microphone according to the present invention; and [0032] FIG. 6 is a diagram showing output results of the above embodiment at different frequencies. [Main component symbol description] [0033] 1.......Microelectromechanical condenser microphone [0034] 2.......Back plate [0035] 3.......Vibration film [ 0036] 4....... spacer [0037] 5....... sound hole [0038] 6....... 矽 substrate [0039] 7....... back Cavity [0040] 8. [Substrate [0041] 9....... Metal cover [0042] 10....... Conversion wafer [0043] 20... Microelectromechanical condenser microphone [0044] 21.......Base 099115379 Form No. A0101 Page 12 of 24 0992027245-0 201141245 [0045] [0048] [0049] [0049] [0051] [0055] [0055] [0057] [0057] Ο 22 ... rigid diaphragm 23 ... ... elastic element 24 ... ....Back plate 25 .... Sound hole 26 .... Back cavity 27 .... Support 28 · · 29 ·. 30 ·. 31 .. 32 · 33 ·. 34 ·. Insulators polycrystalline layer intermediate layer polycrystalline stone layer ••Structural strengthening part.. two ' \ •• chopping board.:.... 丨 "disease: .. trench
099115379 表單編號A0101 第13頁/共24頁 0992027245-0099115379 Form No. A0101 Page 13 of 24 0992027245-0