1. An inkjet print head comprising:
an inkjet board having an ink passage therein; and
a cutting portion provided outside the ink passage in cross section in a longitudinal direction of the inkjet board, having a cutting surface created by separation into head chip units of the inkjet board, and having a cutting mark comprising a cut trace provided on the cutting surface.
2. The inkjet print head of claim 1, wherein the cutting mark has surface roughness higher than another portion in cross section in the longitudinal direction.
3. The inkjet print head of claim 1, wherein the cutting surface comprises a portion provided outside the cutting mark and having surface roughness smaller than the cutting mark.
4. The inkjet print head of claim 1, wherein a portion having relatively small surface roughness is provided within the cutting mark.
5. The inkjet print head of claim 1, further comprising an auxiliary cutting portion provided from one surface of the cutting portion inwardly in a thickness direction of the inkjet board, and assisting the separation into head chip units of the inkjet board.
6. An inkjet print head comprising:
an inkjet board having an ink passage therein;
a cutting portion provided outside the ink passage of the inkjet board and having a cutting surface created by separation into head chip units of the inkjet board; and
an auxiliary cutting portion provided from one surface of the cutting portion inwardly in a thickness direction of the inkjet board, and assisting the separation into head chip units of the inkjet board.
7. The inkjet print head of claim 6, wherein the auxiliary cutting portion comprises at least one through hole formed through the inkjet board.
8. The inkjet print head of claim 6, wherein the auxiliary cutting portion comprises at least one recess provided from the one surface of the cutting portion inwardly in the thickness direction of the inkjet board.
9. A method of manufacturing an inkjet print head, the method comprising:
forming a plurality of ink passages in an upper board and a lower board in order to form a wafer having a plurality of inkjet print heads continuously arrayed thereon;
etching end portions of the plurality of ink passages in a longitudinal direction of the inkjet print heads in order to expose nozzles being the end portions of the ink passages while forming connection portions outside the ink passages;
forming the wafer by bonding the upper board and the lower board to each other;
cutting the wafer in order to expose side surfaces in the longitudinal direction of the inkjet print heads; and
cutting the connecting portions.
10. The method of claim 9, further comprising partially etching the connecting portions in order to facilitate the cutting of the connecting portions to thereby form through holes formed through the inkjet print heads.
11. The method of claim 9, further comprising partially etching the connecting portions in order to facilitate the cutting of the connecting portions to thereby form recesses provided inwardly in a thickness direction of the inkjet print heads.
12. The method of claim 9, wherein the forming of the wafer is performed by silicon direct bonding (SDB) of the upper board and the lower board.
13. The method of claim 9, wherein above operations are performed in a sequential manner.
14. The method of claim 9, wherein the cutting of the wafer is performed by using a dicing process.
15. The method of claim 9, wherein the cutting of the connecting portions comprises forming cutting marks comprising cut traces on cutting surfaces of the connecting portions.
16. The method of claim 9, wherein the cutting of the connecting portions is performed so that surface roughness of cutting marks to be formed on cutting surfaces of the connecting portions is higher than that of another portion in cross section in the longitudinal direction of the inkjet print heads.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A high-frequency amplifier comprising:
a first field effect transistor for performing amplification, a source of the first field effect transistor is configured to be grounded; and
a stabilizing circuit connected to a gate of the first field effect transistor, the stabilizing circuit having an impedance which changes so as to increase as the voltage of a drain of the first field effect transistor increases.
2. The high-frequency amplifier according to claim 1, wherein the stabilizing circuit is provided with first and second capacitors, at least one second field effect transistor and a resistor, one end of the first capacitor is connected to the gate of the first field effect transistor, a drain of the second field effect transistor is connected to the other end of the first capacitor, a gate of the second field effect transistor is grounded, a source of the second field effect transistor is connected to the drain of the first field effect transistor, one end of the resistor is grounded and the other end of the resistor is connected to the source of the second field effect transistor, one end of the second capacitor is grounded, and the other end of the second capacitor is connected to the source of the second field effect transistor in parallel with the resistor.
3. The high-frequency amplifier according to claim 1, further comprising a series circuit of a second resistor and a third capacitor connected serially with each other, the series circuit being provided in parallel with the stabilizing circuit, wherein one end of the second resistor is connected to the gate of the first field effect transistor, and one end of the third capacitor is grounded.
4. The high-frequency amplifier according to claim 2, further comprising a series circuit of a second resistor and a third capacitor connected serially with each other, the series circuit being provided in parallel with the stabilizing circuit, wherein one end of the second resistor is connected to the gate of the first field effect transistor, and one end of the third capacitor is grounded.