JPH04110161A - Thermal head heating resistor and thermal head using same - Google Patents
Thermal head heating resistor and thermal head using sameInfo
- Publication number
- JPH04110161A JPH04110161A JP22885090A JP22885090A JPH04110161A JP H04110161 A JPH04110161 A JP H04110161A JP 22885090 A JP22885090 A JP 22885090A JP 22885090 A JP22885090 A JP 22885090A JP H04110161 A JPH04110161 A JP H04110161A
- Authority
- JP
- Japan
- Prior art keywords
- polycrystalline silicon
- thermal head
- film
- active layer
- heating element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 35
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims abstract description 36
- 239000000758 substrate Substances 0.000 claims abstract description 13
- 239000010409 thin film Substances 0.000 claims abstract description 4
- 239000010408 film Substances 0.000 abstract description 22
- 239000012535 impurity Substances 0.000 abstract description 10
- 238000000034 method Methods 0.000 abstract description 9
- 238000004518 low pressure chemical vapour deposition Methods 0.000 abstract description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 5
- 239000000919 ceramic Substances 0.000 abstract description 2
- 230000001590 oxidative effect Effects 0.000 abstract description 2
- 229910052681 coesite Inorganic materials 0.000 abstract 1
- 229910052906 cristobalite Inorganic materials 0.000 abstract 1
- 239000000377 silicon dioxide Substances 0.000 abstract 1
- 235000012239 silicon dioxide Nutrition 0.000 abstract 1
- 229910052682 stishovite Inorganic materials 0.000 abstract 1
- 229910052905 tridymite Inorganic materials 0.000 abstract 1
- 239000000463 material Substances 0.000 description 3
- 239000010453 quartz Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 229920005591 polysilicon Polymers 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Electronic Switches (AREA)
Abstract
Description
【発明の詳細な説明】
〔技術分野〕
本発明は、感熱記録方式によるファクシミリ、プリンタ
等に用いられるサーマルヘッドおよびそれに使用される
発熱抵抗体に関する。DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a thermal head used in a thermal recording facsimile, a printer, etc., and a heating resistor used therein.
感熱記録は、■無騒音であること、■機構が簡単なため
機器が低コストであること、（ルメンテナンスが不要で
あることなどの面で光学記録やインパクト記録等の他方
式よりもすぐれており、現在量も普及しているプリント
方式の１つである。Thermal recording is superior to other methods such as optical recording and impact recording in that it is noiseless, has a simple mechanism and is low cost, and requires no maintenance. This is one of the printing methods that is currently popular.
サーマルヘッドは、このプリント方式に用いるものであ
って、ファクシミリをはじめとして、その記録スピード
の向上とともに、プリンタ、プロッタ、−数計測用及び
ＭＥ用レコーダ、コンピュータ端末などの高速記録分野
でも市場が拡大しつつある。Thermal heads are used in this printing method, and as the recording speed improves, the market for facsimiles and other applications is expanding in high-speed recording fields such as printers, plotters, recorders for counting and ME, and computer terminals. It is being done.
サーマルヘッドは印字を行う発熱部とそれを駆動するド
ライバーＩＣからなっており、電流を流すことによって
発熱し印字を行う。前記ドライバーＩＣはＣＭＯ５ある
いはＢｉ−ＣＭＯ５のチップであり、これらはワイヤー
ボンディングによって接続されている。The thermal head consists of a heat generating section that performs printing and a driver IC that drives it, and generates heat and performs printing by passing an electric current through it. The driver IC is a CMO5 or Bi-CMO5 chip, and these are connected by wire bonding.
前記のようなサーマルヘッドは、高解像度化やドツト数
の増加に対してワイヤボンディング等の実装上の制限が
与えられ、サーマルヘッドの小型化、低価格化を困難に
している。The thermal head as described above is subject to mounting restrictions such as wire bonding in response to higher resolution and an increase in the number of dots, making it difficult to reduce the size and cost of the thermal head.
そのため、基板に石英を用い、訃動回路を多結晶シリコ
ン（以下ポリシリコンと称す）薄膜トランジスタで構成
し、かつ、その製作工程でポリシリコンを発熱体として
形成することにより、ＩＣチップを使用せず、同一基板
上に能動回路と発熱体を一体化することが多数提案され
てきている。Therefore, by using quartz for the substrate, configuring the passive circuit with polycrystalline silicon (hereinafter referred to as polysilicon) thin film transistors, and forming polysilicon as a heating element in the manufacturing process, we can eliminate the use of IC chips. Many proposals have been made to integrate an active circuit and a heating element on the same substrate.
たとえば、特開昭６２−２０４９６４号公報では同一絶
縁基板上に多結晶シリコンからなる発熱体と多結晶シリ
コンＴＰＴｆＪ動回路を形成している。For example, in Japanese Patent Laid-Open No. 62-204964, a heating element made of polycrystalline silicon and a polycrystalline silicon TPTfJ dynamic circuit are formed on the same insulating substrate.
しかして、サーマルヘッドにおいては、発熱抵抗体の特
性が印字品質に大きく影響する。中でもサーマルヘッド
の高密度、高速性、低電力駆動化のために、抵抗体材料
の高抵抗化と熱的安定性が要求される。ところが、多結
晶シリコンを抵抗体として用いる場合、比抵抗が温度に
よって変化するため熱的に不安定であるという問題があ
る。Therefore, in the thermal head, the characteristics of the heating resistor greatly affect the printing quality. Above all, high resistance and thermal stability of the resistor material are required to achieve high density, high speed, and low power driving of thermal heads. However, when polycrystalline silicon is used as a resistor, there is a problem that it is thermally unstable because its specific resistance changes depending on the temperature.
本発明は上記した問題点を解消し、より生産性を高くし
、小型化、高密度化、高速化をはかったサーマルヘッド
およびその発熱抵抗体を提供することを目的としている
。SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a thermal head and its heating resistor which are more productive, smaller in size, higher in density, and faster in speed.
上記目的を達成するため、本発明者は鋭意研究を重ねた
結果、抵抗体としての多結晶シリコンの熱的安定性は、
室温での比抵抗値を成る範囲に規定することが有効なこ
とを確認し、本発明を完成するに至った。In order to achieve the above object, the inventor of the present invention has conducted intensive research and found that the thermal stability of polycrystalline silicon as a resistor is as follows:
The present inventors have confirmed that it is effective to define the specific resistance value at room temperature within the following range, and have completed the present invention.
すなわち本発明の１つは、室温で比抵抗が０．００２〜
０．３Ω・ｃｍの多結晶シリコンであることを特徴とす
るサーマルヘッド用発熱抵抗体に関する。That is, one aspect of the present invention is that the specific resistance is 0.002 to 0.002 at room temperature.
The present invention relates to a heating resistor for a thermal head, characterized in that it is made of polycrystalline silicon of 0.3 Ω·cm.
本発明の他の１つは、同一の絶縁基板上に発熱抵抗体と
その駆動回路部とを有するサーマルヘッドにおいて、発
熱抵抗体と駆動回路用薄膜トランジスタの活性層または
ゲート電極が、室温での比抵抗が０．００２〜０．３Ω
・ｃｍの多結晶シリコンであることを特徴とするサーマ
ルヘッドに関する。Another aspect of the present invention is that in a thermal head having a heat generating resistor and its driving circuit portion on the same insulating substrate, the active layer or gate electrode of the heating resistor and the thin film transistor for the driving circuit have a ratio at room temperature. Resistance is 0.002~0.3Ω
-Regarding a thermal head characterized by being made of cm polycrystalline silicon.
本発明の構成と作用を説明する。The structure and operation of the present invention will be explained.
半導体の比抵抗は、温度によって変化する。The resistivity of semiconductors changes depending on temperature.
また、不純物濃度を変えると、比抵抗値および抵抗温度
係数が変わる。不純物濃度が比較的低い領域においては
、温度が上昇すると、抵抗が下がる。すなわち負の抵抗
温度係数をもつ。また、不純物濃度が高いほど、抵抗は
低く、かつ、抵抗温度係数の絶対値は小さくなる。不純
物濃度がさらに高い領域においては、正の抵抗温度係数
をもち、濃度が高いほど抵抗は低く、かつ抵抗温度係数
は大きくなる。多結晶シリコンも上記性質をもつことが
実験により確められた。Further, when the impurity concentration is changed, the specific resistance value and the resistance temperature coefficient change. In a region where the impurity concentration is relatively low, as the temperature increases, the resistance decreases. In other words, it has a negative temperature coefficient of resistance. Furthermore, the higher the impurity concentration, the lower the resistance and the smaller the absolute value of the temperature coefficient of resistance. A region with a higher impurity concentration has a positive temperature coefficient of resistance, and the higher the concentration, the lower the resistance and the larger the temperature coefficient of resistance. Experiments have confirmed that polycrystalline silicon also has the above properties.
ここで、不純物濃度による抵抗値の違いは、室温では大
きいが、発熱時の温度（３００〜５００℃）では小さい
。したがって、発熱抵抗体に適した材料として、比抵抗
がある程度大きく抵抗温度係数が小さい多結晶シリコン
を使用することができる。Here, the difference in resistance value depending on the impurity concentration is large at room temperature, but small at the temperature during heat generation (300 to 500° C.). Therefore, polycrystalline silicon, which has a certain degree of specific resistance and a small temperature coefficient of resistance, can be used as a suitable material for the heating resistor.
また、この多結晶シリコン発熱体は、ＴＦＴ跣動回動回
路部性層多結晶シリコン膜または、多結晶シリコンのゲ
ート電極と同一基板上に同時に形成することができる。Further, this polycrystalline silicon heating element can be formed simultaneously on the same substrate as the polycrystalline silicon film or polycrystalline silicon gate electrode for the TFT rotation circuit.
本発明では、上記のような点を基礎に多結晶シリコンの
比抵抗範囲を決定した。すなわち、サーマルヘッドの印
字濃度は、発熱体による熱量に依存する。この熱量は発
熱体の抵抗値と、それに流す電流値によって決まり電流
の大きさにより制御できる。しかし、発熱体の抵抗が温
度によって大きく変化すると、安定した印字を行うため
の電流値の設定が難しくなる。そのため、本発明では発
熱体の抵抗温度係数の絶対値を１１０００Ｐｐ／ ’Ｃ
とし、抵抗値の変動が熱量に大きく影響しないようにし
た。ｐｏｌｙ−５ｉを発熱体とした場合第２図の関係か
ら、比抵抗が０．００２〜０．３Ω・ｌとなるように不
純物ドープ量を調節すれば上記条件を満足させることが
できる。In the present invention, the specific resistance range of polycrystalline silicon is determined based on the above points. That is, the print density of the thermal head depends on the amount of heat generated by the heating element. The amount of heat is determined by the resistance value of the heating element and the value of the current flowing through it, and can be controlled by the magnitude of the current. However, if the resistance of the heating element changes significantly depending on the temperature, it becomes difficult to set the current value for stable printing. Therefore, in the present invention, the absolute value of the temperature coefficient of resistance of the heating element is set to 11000Pp/'C.
This ensures that fluctuations in resistance do not have a large effect on the amount of heat. When poly-5i is used as a heating element, the above conditions can be satisfied by adjusting the amount of impurity doping so that the specific resistance is 0.002 to 0.3 Ω·l from the relationship shown in FIG.
実施例１
以下に本発明の実施例を示す。第１図は１石英基板上に
ＬＰＣＶＤ法により多結晶シリコン膜（１（１００人）
を形成し、その後ボロンを色々な濃度でイオン注入した
ものについて、室温から４００℃までの温度領域で、比
抵抗を測定した結果得られたもので、抵抗温度係数と室
温での比抵抗との関係を示している。サーマルヘッドと
して実用的な印字品質を得るために発熱体の抵抗温度係
数の絶対値を１１０００ｐｐ／’Ｃ以下にする必要があ
る。したがって第２図から、室温での比抵抗が０．００
２〜０，３Ω・ｃｍの多結晶シリコンがこの条件を満足
し、発熱体として使えることを示す。Example 1 Examples of the present invention are shown below. Figure 1 shows a polycrystalline silicon film (1 (100 people)) deposited on a quartz substrate by the LPCVD method.
This is the result of measuring the resistivity in the temperature range from room temperature to 400 degrees Celsius for the products in which boron was ion-implanted at various concentrations. It shows a relationship. In order to obtain practical printing quality as a thermal head, the absolute value of the temperature coefficient of resistance of the heating element must be 11000 pp/'C or less. Therefore, from Figure 2, the specific resistance at room temperature is 0.00
It is shown that polycrystalline silicon of 2 to 0.3 Ω·cm satisfies this condition and can be used as a heating element.
第１図は、上記多結晶シリコン発熱体と同一基板上に設
けたＴＦＴＩＩＨ動回路からなるサーマルヘッドの一例
を示す。まず、石英、ガラス、セラミックなどの基板１
に５ｉｎ２等の絶縁層２をＬＰＣＶＤ法などにより形成
する。ただし、この膜は場合によっては無くともよい。FIG. 1 shows an example of a thermal head consisting of a TFTIIH dynamic circuit provided on the same substrate as the polycrystalline silicon heating element. First, a substrate 1 made of quartz, glass, ceramic, etc.
Then, an insulating layer 2 of 5 in 2 or the like is formed by LPCVD method or the like. However, this film may be omitted depending on the case.
次にＬＰＣＶＤ法などによりＴＰＴ活性層として多結晶
シリコン膜３を形成する。これを熱酸化することによっ
てゲート絶縁膜４を形成する。なお、絶縁膜４は、ＬＰ
ＣＶＤ法などによって形成してもよく、この場合、シリ
コン窒化膜としてもよい。次にゲート電極として多結晶
シリコン膜５をＬＰＧＶＤなどにより形成する。この膜
は同時に発熱体用多結晶シリコン膜６としても使われる
。活性層３の両端は、不純物がドープされ、ソース、ド
レイン領域を構成する。また、ゲート電極５と発熱体６
に不純物をドープすることにより、ゲート電極を低抵抗
化し、発熱体の抵抗温度係数を減らす。その後、絶縁層
７を形成して、フォトリソ、エツチングによりコンタク
トホールを設けて電極８，９．１０を形成する。その上
に耐酸化層１１と耐摩耗層１２を全面に形成する。Next, a polycrystalline silicon film 3 is formed as a TPT active layer by LPCVD or the like. A gate insulating film 4 is formed by thermally oxidizing this. Note that the insulating film 4 is made of LP
It may be formed by a CVD method or the like, and in this case, it may be a silicon nitride film. Next, a polycrystalline silicon film 5 is formed as a gate electrode by LPGVD or the like. This film is also used as a polycrystalline silicon film 6 for a heating element. Both ends of the active layer 3 are doped with impurities to form source and drain regions. In addition, the gate electrode 5 and the heating element 6
By doping impurities into the gate electrode, the resistance of the gate electrode is lowered and the temperature coefficient of resistance of the heating element is reduced. Thereafter, an insulating layer 7 is formed, contact holes are provided by photolithography and etching, and electrodes 8, 9, and 10 are formed. Thereon, an oxidation-resistant layer 11 and a wear-resistant layer 12 are formed over the entire surface.
別個として、発熱体６は活性層３と同時に形成すること
もできる。Separately, the heating element 6 can also be formed simultaneously with the active layer 3.
実施例２
実施例１と同様の構成とする。ただしＴＰＴ活性層３を
形成する時に、同時に発熱体層６を形成する。また、ソ
ース・ドレイン領域形成のだめの不純物ド−ピング時に
同時に発熱体６へのドープを行う。Example 2 The configuration is similar to that of Example 1. However, when forming the TPT active layer 3, the heating element layer 6 is formed at the same time. Furthermore, the heating element 6 is doped at the same time as the impurity doping for forming the source/drain regions.
本発明は、以上説明したように構成されており、本発明
における多結晶シリコン膜は、室温での抵抗値を０．０
０２〜０．３Ω・ａｍとすることで抵抗温度係数を絶対
値で１１０００ｐｐ／ ’Ｃ以下にすることができ、サ
ーマルヘッド用発熱抵抗体として優れた特性を発揮する
ことができる。The present invention is configured as described above, and the polycrystalline silicon film in the present invention has a resistance value of 0.0 at room temperature.
By setting the resistance temperature coefficient to 02 to 0.3 Ω·am, the absolute value of the temperature coefficient of resistance can be reduced to 11000 pp/'C or less, and excellent characteristics can be exhibited as a heating resistor for a thermal head.
また、多結晶シリコン膜により構成されたサーマルヘッ
ドにおいては、発熱体材料とＴＰＴ駆動回路のゲート電
極または活性層とを同じ多結晶シリコン膜を用いて同一
基板上に両者を同時に形成しているので、より生産性を
高く、小型化、高密度化、高速化をはかることができ。Furthermore, in a thermal head made of a polycrystalline silicon film, the heating element material and the gate electrode or active layer of the TPT drive circuit are formed simultaneously on the same substrate using the same polycrystalline silicon film. , higher productivity, smaller size, higher density, and faster speed.
産業上極めて有用である。It is extremely useful in industry.
第１図は、本発明の多結晶シリコン発熱体と同一基板上
に設けたＴＰＴＩＩ動回路からなるサーマルヘッドの断
面図であり、第２図は多結晶シリコンの抵抗温度係数（
０〜４００℃）と室温における比抵抗（対数目盛）との
関係を示すグラフである。
１・・・基板 ２・・・絶縁膜３・・多結
晶シリコン活性層
４・・・ゲート絶縁膜
５・・・多結晶シリコンゲート電極
６・多結晶シリコン発熱抵抗体FIG. 1 is a cross-sectional view of a thermal head consisting of a TPTII dynamic circuit provided on the same substrate as the polycrystalline silicon heating element of the present invention, and FIG. 2 shows the temperature coefficient of resistance of polycrystalline silicon (
0 to 400° C.) and specific resistance (logarithmic scale) at room temperature. 1: Substrate 2: Insulating film 3: Polycrystalline silicon active layer 4: Gate insulating film 5: Polycrystalline silicon gate electrode 6: Polycrystalline silicon heating resistor
Claims (1)
晶シリコンであることを特徴とするサーマルヘッド用発
熱抵抗体。 ２、同一の絶縁基板上に発熱抵抗体とその駆動回路部と
を有するサーマルヘッドにおいて、発熱抵抗体と駆動回
路用薄膜トランジスタの活性層またはゲート電極が、室
温での比抵抗が０．００２〜０．３Ω・ｃｍの多結晶シ
リコンであることを特徴とするサーマルヘッド。[Claims] 1. A heating resistor for a thermal head, characterized in that it is made of polycrystalline silicon with a specific resistance of 0.002 to 0.3 Ω·cm at room temperature. 2. In a thermal head having a heating resistor and its driving circuit on the same insulating substrate, the heating resistor and the active layer or gate electrode of the driving circuit thin film transistor have a specific resistance of 0.002 to 0 at room temperature. A thermal head characterized by being made of .3Ω・cm polycrystalline silicon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22885090A JPH04110161A (en) | 1990-08-30 | 1990-08-30 | Thermal head heating resistor and thermal head using same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22885090A JPH04110161A (en) | 1990-08-30 | 1990-08-30 | Thermal head heating resistor and thermal head using same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04110161A true JPH04110161A (en) | 1992-04-10 |
Family
ID=16882855
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22885090A Pending JPH04110161A (en) | 1990-08-30 | 1990-08-30 | Thermal head heating resistor and thermal head using same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04110161A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0778139A1 (en) * | 1995-12-06 | 1997-06-11 | Hewlett-Packard Company | Integrated thin-film drive head for thermal ink-jet printer |
| US6132032A (en) * | 1999-08-13 | 2000-10-17 | Hewlett-Packard Company | Thin-film print head for thermal ink-jet printers |
-
1990
- 1990-08-30 JP JP22885090A patent/JPH04110161A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0778139A1 (en) * | 1995-12-06 | 1997-06-11 | Hewlett-Packard Company | Integrated thin-film drive head for thermal ink-jet printer |
| US6758552B1 (en) | 1995-12-06 | 2004-07-06 | Hewlett-Packard Development Company | Integrated thin-film drive head for thermal ink-jet printer |
| US6132032A (en) * | 1999-08-13 | 2000-10-17 | Hewlett-Packard Company | Thin-film print head for thermal ink-jet printers |
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